Skip to content
naulon

No retraction, correction or concern found when last checked on Oct 23, 2026.

Preconception care: nutritional risks and interventions

Sohni V Dean, Zohra S Lassi, Ayesha M Imam and 1 more (opens in a new tab)

Reproductive Health · 2014 · Meta-analysis

doi:10.1186/1742-4755-11-s3-s3 (opens in a new tab)

Abstract

Introduction. There is increasingly a double burden of under-nutrition and obesity in women of reproductive age. Preconception underweight or overweight, short stature and micronutrient deficiencies all contribute to excess maternal and fetal complications during pregnancy.

Methods. A systematic review and meta-analysis of the evidence was conducted to ascertain the possible impact of preconception care for adolescents, women and couples of reproductive age on maternal, newborn and child health (MNCH) outcomes. A comprehensive strategy was used to search electronic reference libraries, and both observational and clinical controlled trials were included. Cross-referencing and a separate search strategy for each preconception risk and intervention ensured wider study capture.

Results. Maternal pre-pregnancy weight is a significant factor in the preconception period with underweight contributing to a 32% higher risk of preterm birth, and obesity more than doubling the risk for preeclampsia, gestational diabetes. Overweight women are more likely to undergo a Cesarean delivery, and their newborns have higher chances of being born with a neural tube or congenital heart defect. Among nutrition-specific interventions, preconception folic acid supplementation has the strongest evidence of effect, preventing 69% of recurrent neural tube defects. Multiple micronutrient supplementation shows promise to reduce the rates of congenital anomalies and risk of preeclampsia. Although over 40% of women worldwide are anemic in the preconception period, only one study has shown a risk for low birth weight.

Conclusion. All women, but especially those who become pregnant in adolescence or have closely-spaced pregnancies (inter-pregnancy interval less than six months), require nutritional assessment and appropriate intervention in the preconception period with an emphasis on optimizing maternal body mass index and micronutrient reserves. Increasing coverage of nutrition-specific and nutrition-sensitive strategies (such as food fortification; integration of nutrition initiatives with other maternal and child health interventions; and community based platforms) is necessary among adolescent girls and women of reproductive age. The effectiveness of interventions will need to be simultaneously monitored, and form the basis for the development of improved delivery strategies and new nutritional interventions.

Full text

From PubMed Central, U.S. National Library of Medicine, as current on Oct 23, 2026. Paragraph numbers are ours, so an answer can point at one.

Introduction

Nutritional status is an important aspect of health and wellness before and during pregnancy. Under nutrition in women contributes to 20% of maternal deaths, and is a significant risk factor for stillbirths, preterm births, small for gestational age and low birth weight babies, yet in most countries 10-20% of women are underweight. Maternal short stature heightens the risk for obstructed labor, obstetric fistula and maternal mortality, as well as birth asphyxia leading to neonatal death, and is often the result of girls being stunted since childhood. Pre-pregnancy overweight and obesity has been linked to two of the foremost causes of maternal mortality - hypertensive disorders of pregnancy and gestational diabetes mellitus (GDM)- as well as an entire spectrum of adverse pregnancy outcomes, including poor lactation practices, obstetric anesthesia-related complications, prolonged gestation, maternal infectious morbidity and decreased success with trial of labor. Maternal obesity is a cause for stillbirths, fetal and neonatal death, and moreover, perpetuates the obesity epidemic since children of obese women are more likely to be obese themselves.

In addition to weight, micronutrient status is also linked to pregnancy outcomes. The recent Cochrane review found a strong protective effect (RR 0.28, 95% CI 0.15-0.52) of folic acid on recurrent neural tube defects (NTDs). Other meta-analyses of randomized and observational studies showed a reduction in recurrence risk of 69 to 100% and a reduction in occurrence risk of 42 to 62%, yet less than half of all women regularly consume folic acid before conception. Despite research evidence linking iron deficiency with maternal mortality, around 40% of women are anemic globally. Other micronutrients such as zinc and calcium have been found to improve maternal and newborn outcomes when supplementation is provided during pregnancy- it seems likely that ensuring adequate intake of these micronutrients earlier, which is during the preconception period, would be of added benefit for undernourished girls and women and in the case of unplanned pregnancies. Folic acid, B vitamins and zinc have been shown to affect early fetal development, even before women realize they are pregnant. Micronutrient supplementation or fortification is currently being used as strategies to improve nutrition even in resource-poor settings since many girls and women are chronically undernourished.

There is a dearth of intervention trials to address under-nutrition or obesity in women of reproductive age. Weight and micronutrient status during pregnancy is influenced by a number of factors such as food insecurity and birth spacing that require broad interventions, hence the aim should to achieve and sustain optimal nutritional intake and weight before pregnancy. In addition, even for women who are overweight or obese, losing weight is not recommended during gestation and therefore weight and nutritional status should be reviewed between pregnancies. Nutritional risks and interventions are an important component of preconception care, defined for the purpose of this review as “any intervention provided to women and couples of childbearing age, regardless of pregnancy status or desire, before pregnancy, to improve health outcomes for women, newborns and children” (Detailed discussion of the importance and scope of preconception care is given elsewhere).

This paper presents the findings of a systematic review that was undertaken to consolidate the evidence for nutritional risks before pregnancy, and ascertain the effectiveness of providing interventions during the preconception period (versus periconception or prenatal) on maternal, newborn and child health (MNCH) outcomes. The first section discusses pre-pregnancy weight, which is followed by diet and exercise as interventions to achieve and maintain optimal weight. This is followed by the sections on folic acid, multivitamin and iron supplementation in the preconception period. The review also looks beyond efficacy of an intervention to studies that examined impact of strategies used to increase uptake.

Methods

We systematically reviewed all literature published up to 2011 to identify studies describing the effectiveness of preconception (period before pregnancy and between pregnancies) nutritional risks and interventions and their impact on maternal, newborn and child health (MNCH) outcomes. Electronic databases such as PubMed, Cochrane Libraries, Embase, and WHO Regional Databases were searched to identify the studies. We included systematic reviews, experimental and observational studies. Papers were also identified by hand searching references from included studies. No language or date restrictions were applied in the search. The findings were presented at international meeting and shared with professionals in the relevant fields of maternal and child health, following which results were updated based on current searches (through end of 2012) and expert opinion. Studies were included if they reported the nutritional risks and interventions for MNCH outcomes. Methodology is described in detail elsewhere.

For the studies that met the final inclusion criteria, two review authors abstracted data describing study identifiers and context, study design, intervention specifics and outcome effects into a standardized abstraction sheets. The quality of experimental studies were assessed using Cochrane criteria, whereas STROBE guidelines were used to assess the quality of observational studies. We conducted meta-analyses for individual studies and pooled statistics was reported as the odds ratio (OR) and relative risk (RR) between the experimental and control groups with 95% confidence intervals (CI). Mantel–Haenszel pooled RR and corresponding 95% CI were reported or the Der Simonian–Laird pooled RR and corresponding 95% CI where there was an unexplained heterogeneity. All analyses were conducted using the software Review Manager 5.1. Heterogeneity was quantified by Chi2 and I2, in situations of high heterogeneity, causes were explored and random effect models were used.

Results

The review identified 2034 papers from search in all databases. After the initial title and abstract screening, 198 full texts were reviewed to identify papers which met the inclusion criteria and had the outcomes of our interest. One hundred and forty six studies were finally selected for abstraction and analysis (Figure 1). Information related to each included study can be found on the following link: https://globalmotherchildresearch.tghn.org/site_media/media/articles/Preconception_Report.pdf

Maternal pre-pregnancy weight

In order to define the categories of weight that are not normal, the World Health Organization and the National Institutes of Health grouped weight into four categories according to individuals’ body mass index: underweight (<18.5 kg/m2), normal (18.5–24.9 kg/m2), overweight (25.0-29.9 kg/m2), and obese (30.0 kg/m2). The literature shows a BMI-dependent relationship between pre-pregnancy obesity and adverse pregnancy outcomes. Further, excessive postpartum weight retention is a risk not only for subsequent pregnancies, but also for the development of maternal chronic diseases. Although guidelines exist for gestational weight gain according to maternal pre-pregnancy BMI, however gestational weight gain is not discussed further as it falls outside the scope of preconception care. Previous reviews have assessed maternal overweight and obesity using various cutoff points to define obesity, and have linked them to only one outcome of interest. This review extensively examines any MNCH outcomes that have been reported with all weight categories, grouping the data from individual studies into underweight or overweight and comparing these to women with normal BMI as defined above (please see table for data included here).

The review identified 34 studies that discussed maternal underweight. This review found that pre-pregnancy underweight significantly increases the risk of preterm birth by 32% (RR 1.32, 95% CI 1.22-1.43) (Figure 2). Pre-pregnancy underweight was also found to significantly increase the risk of small-for-gestational age babies (RR 1.64, 95% CI 1.22-2.21)., Although previous work has found a significant effect of pre-pregnancy underweight on the risk of having low birth weight babies (RR 1.64 and OR 1.82, this review found a non-significant risk (RR 1.37, 95% CI 0.46-4.13) perhaps because of the low number of studies included since these were the only ones to assess maternal weight status before pregnancy. No effect was found for pre-pregnancy underweight on hypertensive disorders of pregnancy, GDM, large-for-gestational age or macrosomia, or any congenital birth defects.

The review identified 41 studies that reported outcomes for overweight women. The results presented in this review for the increased risk of hypertensive disorders of pregnancy with maternal overweight are not truly representative of the association since various studies categorized this outcome differently. The risk of preeclampsia (OR 2.28; 95% CI: 2.04-2.55) (Figure 3) and GDM (OR 1.91; 95% CI: 1.58-2.32), however, approximately doubles with pre-pregnancy overweight, and the effect was even greater for pre-pregnancy obesity. The data for impact of pre-pregnancy obesity is not presented since it is similar to the results for maternal overweight. The Pooled analysis of seven observational studies showed a clear increase of 42% in caesarean delivery among overweight women (OR 1.42, 95% CI 1.21-1.66). This review found inconclusive evidence for the effect of pre-pregnancy overweight on preterm births, instrumental delivery, or fetal distress. Perinatal outcomes that were significantly associated with maternal overweight before conception include macrosomia, large-for-gestational age babies (OR 1.63, 95% CI 1.51-1.76), and birth defects-notably neural tube defects and congenital heart defects (OR 1.15, 95% CI 1.07-1.24).

Diet, exercise and weight loss

Consumption of calorie-dense but nutritiously poor foods and physical inactivity are concerning for the health of all people, but disproportionately affect mothers and their young children. Fortunately, weight is a modifiable risk factor and evidence supports weight change as an intervention to improve MNCH outcomes. Although this review demonstrated that maternal underweight increases the chances of preterm birth (25%), and small-for-gestational age babies (64%), the review found a scarcity of evidence for interventions to improve the macro-nutritional status of women before pregnancy.

As shown in the previous section, maternal overweight and obesity is a major risk factor for poor maternal and child outcomes. There is some evidence to support exercise as an intervention to decrease the risk of GDM, preeclampsia, and maternal weight gain, improve birth weight, and increase the chance of a normal delivery. This review expands upon previous work and examines whether diet and/or exercise are effective in reducing weight in women, and if this impacts MNCH outcomes.

The review 23 identified studies. The trials found all used a control group; however they were carried out in women of different ages, and included different interventions. Women in the intervention group lost an average of up to 3.5kg. Interventions that combined calorie restriction and physical activity, involved a support system and monitoring, and were sustained over longer periods effected more weight change. A case control study showed that women with perceived strenuous physical activity before pregnancy had a 78% reduced risk of preeclampsia.

Folic acid supplementation

Folic acid is a B-vitamin whose bioavailability from dietary sources lags behind that achieved through supplementation, and whose deficiency is associated with congenital abnormalities, especially neural tube defects. Multiple case-control, cohort and quasi-randomised controlled trials have been carried out that provide a strong evidence base to support the effectiveness of folic acid supplementation in preventing birth defects and their consequent morbidity and mortality. Folic acid supplementation has thus become a primary periconceptional intervention.

The analyses showed that folic acid has a strong protective effect on preventing recurrent NTDs (RR 0.31, 95% CI 0.14-0.66) when it was restricted to randomized double-blind placebo-controlled studies, however this effect was no longer significant when two observational studies were included- (RR 0.43, 95% CI 0.13-1.40) (Figure 4). The review also found a significant effect of multivitamin supplementation in preventing NTDs, both occurrent and recurrent, although the only included study that did not show a beneficial effect actually separated folic acid from multivitamins, while the rest included folic-acid containing supplements. Hence, it is doubtful that multivitamins without folic acid have a protective effect against NTDs, which is confirmed by the MRC study (RR for multivitamins versus placebo 0.61, 95% CI 0.26-1.45).

Previous reviews have not shown a benefit of folic acid/multivitamin supplementation on orofacial clefts, and although this review added three case-control studies and two prospective cohorts, the effect sizes adhered to unity. However, reviews that include all studies on folic acid/multivitamin supplementation simultaneously do show a modest protective effect, especially for cleft lip.

This review identified 73 studies on the effect of folic acid supplementation and congenital heart defects. The result is mixed at best- pooling of two randomized trials, one cohort and one case-control trial showed a risk reduction of 42% in this analysis (Figure 5).

No review has shown a consistent effect of folic acid/multivitamin supplementation on maternal and pregnancy outcomes- including ectopic pregnancy, miscarriage, stillbirths, preterm births, low birth weight, and other birth defects. Further, the apprehension that widespread folic acid supplementation or fortification would lead to increased rates of multiple gestation was not shown to be significant in this review (RR 0.99, 95% CI 0.94-1.05) or previous work (OR 1.02 with supplementation and maximum annual increase in twinning rates of 4.6% with fortification).

The results from three randomized double-blind placebo-controlled studies yield a 69% reduced risk (RR of 0.31, 95% CI 0.14-0.66) for recurrent NTDs with periconceptional folic acid supplementation. The MRC study probably provides the most accurate estimate for this intervention since it was a multicenter prospective randomized trial. The remaining studies all suffer from low response rates, however, only Suarez et al. 2000 has results inconsistent with the pooled analysis. This could be attributed to recall and selection bias in the study or to primary intake in this population being from dietary sources with lower bioavailability.

Multivitamins supplementation

There is incontrovertible data to support the routine use of multivitamins by women of reproductive age, to improve their own health as well as their potential mother and child outcomes. Although previous systematic reviews and meta-analyses have analysed the unique role of periconceptional folic acid (versus multivitamins) on MNCH outcomes, they have included only randomised and quasi-randomised trials. In addition, while periconceptional supplementation is in itself an intervention, it would have a greater impact if it were implemented for all women with the potential to become mothers. For limb reduction defects (RR ranges from 0.43-0.59 for all analyses) and congenital urinary tract anomalies (RR ranges from 0.17-0.68 for all analyses), the evidence shows a modest but persistent risk reduction with the use of multivitamins, rather than folic acid.

Pooling two cohort studies, the review also found a significant 27% reduction in the risk of preeclampsia (Figure 6) by maternal periconceptional multivitamin supplementation. This review also found a 43% risk reduction of multivitamins for multiple congenital abnormalities (Figure 7).

Pooling data from 5 case-control and 2 cohort-controlled trials conducted in relatively high-income countries (HICs), resulted in a significant 49% decrease in risk (RR 0.51, 95% CI 0.31-0.82) (Figure 8) of occurrent neural tube defects due to periconceptional multivitamin supplementation. The case-control study by Bower & Stanley 1992 was inconsistent with the other study results, possibly owing to the small total number of women using periconceptional multivitamins, or to recall bias among case mothers. There was substantial heterogeneity between studies, however repeat analysis using random effects did not change the results.

A recent community intervention in China provided multivitamins to the intervention group from 3 months pre-pregnancy until the end of the first trimester. The intervention resulted in lower incidence of stillbirth (0.70% in intervention group vs. 1.55% in control group; p <0.001), malformation (0.23% in intervention group vs. 0.70% in control group; p <0.001) and low birth weight (0.39% in intervention group vs. 0.84% in control group; p <0.001) compared to the control group, and better growth indicators at birth.

Iron supplementation

Anemia is a common problem among women of reproductive age, especially in low and middle income countries (LMICs) where low dietary intake of bioavailable iron combined with endemic infectious diseases such as helminthiasis puts women at increased risk in the preconception period. Low preconception hemoglobin and ferritin levels increase the risk of poor fetal growth and low birth weight. The literature shows that iron supplementation during pregnancy can be a protective factor against low birth weight, and given alone or with folic acid it is effective in increasing iron stores and preventing anemia during later gestation.

The review identified 6 studies. Berger et al. tested a weekly combined iron-folic acid intervention in the preconception period among Vietnamese women and similarly found the supplementation significantly improved iron status and reduced anemia when compared to baseline. In the Philippines ferritin levels improved, however hemoglobin lagged behind, possibly due to women being deficient in other micronutrients related to heme formation which were not supplemented during the study. The results of these interventions on a national level were similar to a previous randomized-controlled trial in Bangladesh where iron-folic acid given as a powdered supplement added to food decreased anemia among non-pregnant women; however this benefit did not extend to those women who became pregnant. Recent trials in Vietnam combined iron-folic acid supplementation with intermittent deworming and demonstrated significant reduction in anemia, lower rates of helminthic infection, high compliance, and increase in birth weight in intervention districts versus control. In India, the country with the world’s highest proportion of maternal anemia, the same intervention was carried out in adolescent girls, resulting in a substantial drop in anemia prevalence.

Discussion

Maternal overweight and obesity is a growing problem across the world, but women in LMICs and lower socioeconomic strata continue to be at risk of undernourishment. Both pre-pregnancy overweight and underweight are risk factors for poor maternal and child health outcomes, however overweight and obesity results in significantly greater health risks and associated costs. This review identified the association of maternal underweight with preterm birth and small for gestational age babies and the findings are comparable to previous meta-analysis which showed an increased risk of 29% and another study which showed an increased risk of 37%. Similarly the results on association of pre-pregnancy overweight on pre-eclampsia and GDM is consistent with previous reviews that show the risk of preeclampsia typically doubles for each 5 to 7 kg/m2 increase in BMI; and the OR of developing GDM is 1.97-2.14 for overweight women, and 3.01-3.56 for obese women. The pooled analysis on risk of caseation section and other outcomes are also consistent with previous reviews. Given that weight is a modifiable risk factor, research must now focus on how healthcare interventions and public health campaigns can reduce these risks.

There is a strong need for evidence to demonstrate the effectiveness of interventions to achieve optimal pre-pregnancy weight, especially for those women who are underweight. This review confirms earlier evidence that promoting improvement in diet and exercise through sustained, daily changes, with the help of a support system results in weight loss and higher levels of physical activity. Although preceding work illustrates examples of population-scale interventions, more research is needed to support how small-scale initiatives targeted at women with childbearing potential can be implemented on a wider scale. In HICs countries, obese women are increasingly opting to undergo weight loss surgeries, and a review of laparoscopic adjustable gastric banding (LAGB) shows lower gestational weight gain and better maternal and neonatal outcomes for these women compared to obese women not undergoing LAGB prior to pregnancy; however the outcomes were not improved compared to women of normal weight.

The role of nutrition in promoting health is well defined. What women eat determines more than just their own health, it is also vital to healthy pregnancies and newborns, and in fact research now shows that nutritional status in early childhood affects health throughout life. Pregnancy, or planning for pregnancy, provides an impetus for women to change non-healthful behaviors. Many women are still unaware of how much their nutritional status impacts their pregnancy outcomes, and improving women’s nutrition and weight-related behaviors should therefore begin during their earlier reproductive years.

Folic acid supplementation has been proven to reduce the risk of NTDs, both recurrent and occurrent and the results are confirmed by the meta-analyses undertaken by De-Regil et al. However, further research is needed to show whether this benefit extends to prevention of orofacial clefts and congenital cardiovascular abnormalities. Although major health organizations promote the use of folic acid by women of reproductive age through clinical guidelines and recommendations, and the prevalence of folic acid use is reportedly high in the prenatal period, most women do not use folic acid in the periconceptional period, even if they are aware of its benefits. A recent systematic review demonstrated that even in high income countries, only half of all women use folic acid before conception, therefore protective levels cannot be achieved before the critical period of neural tube closure. Reasons for low prevalence of use are confirmed by other studies and include low maternal education and socioeconomic status; young maternal age; lack of a partner; and unplanned pregnancy. It is necessary therefore to improve awareness and use of folic acid supplements among all women of reproductive age so that even women with unplanned pregnancies are protected.

Multicomponent interventions increase use transiently and do not achieve universal coverage, although those with personal counseling in addition to mass campaigns have been shown to be more effective. Fortification has thus been proposed as a means to prevent approximately half of all NTDs occurring annually and 13% of neonatal mortality attributed to NTDs, especially in areas with high prevalence of NTDs. However, ongoing efforts must be made to supplement women at risk of a recurrent NTDs and women who are more folate-depleted. A novel idea has been to incorporate folate into contraceptive pills, which also helps to bridge the gap between when a woman discovers she is pregnant and neural tube closure, even without periconceptional folate use. In order to provide all women (including those at risk of recurrence) with an adequate dose of folic acid, public health policy in some countries now mandates that staple foods, such as flour, be fortified with folic acid.

The studies on iron demonstrate that large-scale nutritional intervention is feasible in LMICs contexts, and results in better biochemical indices. Given the global magnitude of maternal anemia, however, it is surprising that only one trial further assessed birth weight as a measure of improved maternal and newborn health. Iron fortification of foods such as flour, rice, sugar, juice, and fish or soy sauce in various countries has also been shown to improve iron status among women of reproductive age, but again the analyses of the fortification trials do not assess pregnancy outcomes in the long-term. As with folic acid, preventive iron supplementation may require greater community mobilization and social marketing for increased effectiveness and to contribute to improved women’s and maternal health in developing regions.

Conclusion

Maternal malnutrition remains a serious global health issue, particularly in LMICs. The median prevalence of low body mass index among women in the preconception period is 10.9% among 24 countries with a recent Demographic and Health Survey, while 42% of women are anemic when they become pregnant. Underweight and deficiencies of essential nutrients coupled with the increasing burden of obesity have consequences during pregnancy and for newborns. These negative effects are amplified in adolescents or women with closely-spaced pregnancies since they have depleted nutritional reserves, which results in stillbirths, neonatal deaths, low birth weight and preterm births. Overweight and obesity further predispose to maternal hypertensive disorders and gestational diabetes.

Among nutrition-specific interventions periconceptional folic acid supplementation significantly reduces the risk of recurrent NTDs. There is growing interest in multiple micronutrient supplementation in at-risk populations in whom multiple deficiencies often coexist. Data for multiple micronutrient supplementation from a small number of controlled trials shows a persistent lowering of rates of congenital anomalies and preeclampsia. Other nutrition-specific interventions (iron, calcium, balanced protein energy supplementation) have only been studied in pregnant women, or if they have been studied during the preconception period the outcomes are limited to changes in biochemical markers while pregnancy and birth outcomes were not assessed.

Strategies for implementation of nutrition-specific interventions in the preconception period are needed especially to reach women in low- and middle-income countries. At present, food fortification with micronutrients is noted to be the most cost-effective large scale method. However, different approaches are needed to specifically increase uptake among women of reproductive age, noting the critical links between poor maternal nutritional status and its wide-ranging determinants and consequences. Nutritional-sensitive interventions improve population health, education and development and countries investing in such strategies have had greater gains in both nutrition and health outcomes. Integrating nutrition with maternal and child health initiatives and developing community-based platforms that are able to reach populations are especially promising.

Competing interests

We do not have any financial or non-financial competing interests for this review.

Peer review

Peer review reports are included in additional file 1.

References 242

  1. 1.

    Sebire NJ Jolly M Harris JP Wadsworth J Joffe M Beard RW Regan L Robinson S Maternal obesity and pregnancy outcome: a study of 287213 pregnancies in LondonInternational journal of obesity2001 25811751182

    Not in our library10.1038/sj.ijo.0801670 (opens in a new tab)

  2. 2.

    Arendas K Qiu Q Gruslin A Obesity in pregnancy: pre-conceptional to postpartum consequencesJ Obstet Gynaecol Can2008 306477488

    Not in our library10.1016/s1701-2163(16)32863-8 (opens in a new tab)

  3. 3.

    Hall LF Neubert AG Obesity and pregnancyObstetrical & gynecological survey2005 604253

    Not in our library10.1097/01.ogx.0000158509.04154.9e (opens in a new tab)

  4. 4.

    Rode L Nilas L Wøjdemann K Tabor A Obesity-related complications in Danish single cephalic term pregnanciesObstetrics & Gynecology2005 1053537

    Not in our library10.1097/01.aog.0000152304.39492.1c (opens in a new tab)

  5. 5.

    Rosenberg TJ Garbers S Chavkin W Chiasson MA Prepregnancy weight and adverse perinatal outcomes in an ethnically diverse populationObstetrics & Gynecology2003 1025 Part 11022

    Not in our library10.1016/j.obstetgynecol.2003.07.005 (opens in a new tab)

  6. 6.

    Yu CKH Teoh TG Robinson S Obesity in pregnancyBJOG: An International Journal of Obstetrics & Gynaecology2006 1131011171125

    Not in our library10.1111/j.1471-0528.2006.00991.x (opens in a new tab)

  7. 7.

    Callaway LK Prins JB Chang AM McIntyre HD The prevalence and impact of overweight and obesity in an Australian obstetric populationMedical Journal of Australia2006 184256

    Not in our library10.5694/j.1326-5377.2006.tb00115.x (opens in a new tab)

  8. 8.

    Black RE Allen LH Bhutta ZA Caulfield LE de Onis M Ezzati M Mathers C Rivera J Maternal and child undernutrition: global and regional exposures and health consequencesLancet2008 3719608243260

    Not in our library10.1016/s0140-6736(07)61690-0 (opens in a new tab)

  9. 9.

    Bhutta ZA Chopra M Axelson H Berman P Boerma T Bryce J Bustreo F Cavagnero E Cometto G Daelmans B Countdown to 2015 decade report (2000-10): taking stock of maternal, newborn, and child survivalLancet2012 375973020322044

    Not in our library10.1016/s0140-6736(10)60678-2 (opens in a new tab)

  10. 10.

    Baeten JM Bukusi EA Lambe M Pregnancy complications and outcomes among overweight and obese nulliparous womenAmerican Journal of Public Health2001 913436

    Not in our library10.2105/ajph.91.3.436 (opens in a new tab)

  11. 11.

    Doherty DA Magann EF Francis J Morrison JC Newnham JP Pre-pregnancy body mass index and pregnancy outcomesInternational Journal of Gynecology & Obstetrics2006 953242247

    Not in our library10.1016/j.ijgo.2006.06.021 (opens in a new tab)

  12. 12.

    Bodnar LM Wisner KL Moses-Kolko E Sit DKY Hanusa BH Prepregnancy body mass index, gestational weight gain and the likelihood of major depression during pregnancyThe Journal of clinical psychiatry2009 7091290

    Not in our library10.4088/jcp.08m04651 (opens in a new tab)

  13. 13.

    Leeners B Rath W Kuse S Irawan C Imthurn B Neumaier-Wagner P BMI: new aspects of a classical risk factor for hypertensive disorders in pregnancyClinical Science2006 1118186

    Not in our library10.1042/cs20060015 (opens in a new tab)

  14. 14.

    Robinson HE O’Connell CM Joseph KS McLeod NL Maternal outcomes in pregnancies complicated by obesityObstetrics & Gynecology2005 10661357

    Not in our library10.1097/01.aog.0000188387.88032.41 (opens in a new tab)

  15. 15.

    Samuels-Kalow ME Funai EF Buhimschi C Norwitz E Perrin M Calderon-Margalit R Deutsch L Paltiel O Friedlander Y Manor O Prepregnancy body mass index, hypertensive disorders of pregnancy, and long-term maternal mortalityAmerican journal of obstetrics and gynecology2007 1975490

    Not in our library10.1016/j.ajog.2007.04.043 (opens in a new tab)

  16. 16.

    Chu SY Kim SY Schmid CH Dietz PM Callaghan WM Lau J Curtis KM Maternal obesity and risk of cesarean delivery: a meta analysisObesity Reviews2007 85385394

    Not in our library10.1111/j.1467-789x.2007.00397.x (opens in a new tab)

  17. 17.

    Lu GC Rouse DJ DuBard M Cliver S Kimberlin D Hauth JC The effect of the increasing prevalence of maternal obesity on perinatal morbidity* 1American journal of obstetrics and gynecology2001 1854845849

    Not in our library10.1067/mob.2001.117351 (opens in a new tab)

  18. 18.

    Li R Jewell S Grummer-Strawn L Maternal obesity and breast-feeding practicesAmerican Journal of Clinical Nutrition2003 774931

    Not in our library10.1093/ajcn/77.4.931 (opens in a new tab)

  19. 19.

    Hilson JA Rasmussen KM Kjolhede CL High prepregnant body mass index is associated with poor lactation outcomes among white, rural women independent of psychosocial and demographic correlatesJournal of Human Lactation2004 20118

    Not in our library10.1177/0890334403261345 (opens in a new tab)

  20. 20.

    Saravanakumar K Rao SG Cooper GM Obesity and obstetric anaesthesiaAnaesthesia2006 6113648

    Not in our library10.1111/j.1365-2044.2005.04433.x (opens in a new tab)

  21. 21.

    Stotland NE Washington AE Caughey AB Prepregnancy body mass index and the length of gestation at termAmerican journal of obstetrics and gynecology2007 1974378

    Not in our library10.1016/j.ajog.2007.05.048 (opens in a new tab)

  22. 22.

    Rayco-Solon P Fulford AJ Prentice AM Maternal preconceptional weight and gestational lengthAmerican journal of obstetrics and gynecology2005 192411331136

    Not in our library10.1016/j.ajog.2004.10.636 (opens in a new tab)

  23. 23.

    Myles TD Gooch J Santolaya J Obesity as an independent risk factor for infectious morbidity in patients who undergo cesarean deliveryObstetrics & Gynecology2002 1005 Part 1959

    Not in our library10.1016/s0029-7844(02)02323-2 (opens in a new tab)

  24. 24.

    Bujold E Hammoud A Schild C Krapp M Baumann P The role of maternal body mass index in outcomes of vaginal births after cesareanAmerican journal of obstetrics and gynecology2005 193415171521

    Not in our library10.1016/j.ajog.2005.03.041 (opens in a new tab)

  25. 25.

    Carroll CS Vaginal birth after cesarean section versus elective repeat cesarean delivery: Weight-based outcomes* 1American journal of obstetrics and gynecology2003 188615161522

    Not in our library10.1067/mob.2003.472 (opens in a new tab)

  26. 26.

    Durnwald CP Ehrenberg HM Merce BM The impact of maternal obesity and weight gain on vaginal birth after cesarean section successAmerican journal of obstetrics and gynecology2004 1913954957

    Not in our library10.1016/j.ajog.2004.05.051 (opens in a new tab)

  27. 27.

    Goodall PT Ahn JT Chapa JB Hibbard JU Obesity as a risk factor for failed trial of labor in patients with previous cesarean deliveryAmerican journal of obstetrics and gynecology2005 192514231426

    Not in our library10.1016/j.ajog.2004.12.075 (opens in a new tab)

  28. 28.

    Stephansson O Dickman PW Johansson A Cnattingius S Maternal weight, pregnancy weight gain, and the risk of antepartum stillbirth* 1American journal of obstetrics and gynecology2001 1843463469

    Not in our library10.1067/mob.2001.109591 (opens in a new tab)

  29. 29.

    Cedergren MI Maternal morbid obesity and the risk of adverse pregnancy outcomeObstetrics & Gynecology2004 1032219

    Not in our library10.1097/01.aog.0000107291.46159.00 (opens in a new tab)

  30. 30.

    Kristensen J Vestergaard M Wisborg K Kesmodel U Secher NJ Pre pregnancy weight and the risk of stillbirth and neonatal deathBJOG: An International Journal of Obstetrics & Gynaecology2005 1124403408

    Not in our library10.1111/j.1471-0528.2005.00437.x (opens in a new tab)

  31. 31.

    Nohr EA Bech BH Davies MJ Frydenberg M Henriksen TB Olsen J Prepregnancy obesity and fetal death: a study within the Danish National Birth CohortObstetrical & gynecological survey2005 6117

    Not in our library10.1097/01.aog.0000172422.81496.57 (opens in a new tab)

  32. 32.

    Kitsantas P P L Maternal obesity, health status during pregnancy, and breastfeeding initiation and duration2010

    Not in our library10.3109/14767050903118270 (opens in a new tab)

  33. 33.

    Mesman I R T Bonsel GJ Gemke RJ van der Wal MF Vrijkotte TG Maternal pre-pregnancy body mass index explains infant's weight and BMI at 14 months: results from a multi-ethnic birth cohort study2009

    Not in our library10.1136/adc.2008.137737 (opens in a new tab)

  34. 34.

    Olson CM S M Dennison BA Maternal weight gain during pregnancy and child weight at age 3 years2009

    Not in our library10.1007/s10995-008-0413-6 (opens in a new tab)

  35. 35.

    Ellen A Nohr1 M V Jennifer L Baker1 Thorkild IA Sørensen1 Jorn Olsen1 Kathleen M Rasmussen1 Combined associations of prepregnancy body mass index and gestational weight gain with the outcome of pregnancy1,2,2008

    Not in our library10.1093/ajcn/87.6.1750 (opens in a new tab)

  36. 36.

    Lu GC Rouse DJ DuBard M Cliver S Kimberlin D Hauth JC The effect of the increasing prevalence of maternal obesity on perinatal morbidityAmerican Journal of Obstetrics and Gynecology2001 1854845849

    Not in our library10.1067/mob.2001.117351 (opens in a new tab)

  37. 37.

    De-Regil LM Fernández-Gaxiola AC Dowswell T Peña-Rosas JP Effects and safety of periconceptional folate supplementation for preventing birth defectsCochrane Database of Systematic Reviews2010 10CD00795

    Not in our library10.1002/14651858.cd007950.pub2 (opens in a new tab)

  38. 38.

    Grosse SD Collins JS Folic acid supplementation and neural tube defect recurrence preventionBirth Defects Research Part A: Clinical and Molecular Teratology2007 7911737742

    Not in our library10.1002/bdra.20394 (opens in a new tab)

  39. 39.

    Blom HJ Folic acid, methylation and neural tube closure in humansBirth Defects Research Part A: Clinical and Molecular Teratology2009 854295302

    Not in our library10.1002/bdra.20581 (opens in a new tab)

  40. 40.

    Blencowe H Cousens S Modell B Lawn J Folic acid to reduce neonatal mortality from neural tube disordersInternational Journal of Epidemiology2010 39Supplement 1i110

    Not in our library10.1093/ije/dyq028 (opens in a new tab)

  41. 41.

    Ray JG Vermeulen MJ Meier C Wyatt PR Risk of congenital anomalies detected during antenatal serum screening in women with pregestational diabetesQjm2004 9710651

    Not in our library10.1093/qjmed/hch107 (opens in a new tab)

  42. 42.

    Ramakrishnan U Lowe A Vir S Kumar S Mohanraj R Chaturvedi A Noznesky EA Martorell R Mason JB Public health interventions, barriers, and opportunities for improving maternal nutrition in IndiaFood Nutr Bull2012 332 SupplS7192

    Not in our library10.1177/15648265120332s105 (opens in a new tab)

  43. 43.
  44. 44.

    Dean S Rudan I Althabe F Girard AW Howson C Langer A Lawn J Reeve M-E Teela KC Toledano M Setting research priorities for preconception care in low-and middle-income countries: aiming to reduce maternal and child mortality and morbidityPLoS Med2013 109e1001508

    Not in our library10.1371/journal.pmed.1001508 (opens in a new tab)

  45. 45.

    WHO WHOMeeting to develop a global consensus on preconception care to reduce maternal and childhood mortality and morbidity8211 Geneva: World Health Organization Headquarters

    Not in our library

  46. 46.

    Higgins JPT, Green SCochrane Handbook for Systematic Reviews of Interventions. Version 5.0.0 [updated February 2008]The Cochrane Collaboration2008 Available from http://www.cochranehandbook.org

    Not in our library

  47. 47.

    Brand RA Editorial: standards of reporting: the CONSORT, QUORAM, and STROBE guidelinesClin Orthop Relat Res2009

    Not in our library10.1007/s11999-009-0786-x (opens in a new tab)

  48. 48.

    Review Manager (RevMan). [computer program]. Version 5.0:2008 Copenhagen: Nordic Cochrane Collaboration

    Not in our library

  49. 49.

    World Health OrganizationObesity: Preventing and Managing the Global Epidemic. WHO Obesity Technical Report Series 8942000 Geneva, Switzerland: World Health Organization

    Not in our library

  50. 50.

    Raatikainen K Heiskanen N Heinonen S Transition from Overweight to Obesity Worsens Pregnancy Outcome in a BMI-dependent Manner&astObesity2006 141165171

    Not in our library10.1038/oby.2006.20 (opens in a new tab)

  51. 51.

    Villamor E Cnattingius S Interpregnancy weight change and risk of adverse pregnancy outcomes: a population-based studyThe Lancet2006 368954211641170

    Not in our library10.1016/s0140-6736(06)69473-7 (opens in a new tab)

  52. 52.

    Hoff GL Cai J Okah FA Dew PC Pre-Pregnancy Overweight Status between Successive Pregnancies and Pregnancy OutcomesJournal of Women's Health2009 18914131417

    Not in our library10.1089/jwh.2008.1290 (opens in a new tab)

  53. 53.

    Joseph NP Hunkali KB Wilson B Morgan E Cross M Freund KM Pre-pregnancy body mass index among pregnant adolescents: gestational weight gain and long-term post partum weight retentionJournal of Pediatric and Adolescent Gynecology2008 214195200

    Not in our library10.1016/j.jpag.2007.08.006 (opens in a new tab)

  54. 54.

    Ota E Haruna M Suzuki M Anh DD Tho LH Tam NTT Thiem VD Anh NTH Isozaki M Shibuya K Maternal body mass index and gestational weight gain and their association with perinatal outcomes in Viet NamBulletin of the World Health Organization2011 892127136

    Not in our library10.2471/blt.10.077982 (opens in a new tab)

  55. 55.

    Abenhaim HA Kinch RA Morin L Benjamin A Usher R Effect of prepregnancy body mass index categories on obstetrical and neonatal outcomesArchives of Gynecology and Obstetrics2007 27513943

    Not in our library10.1007/s00404-006-0219-y (opens in a new tab)

  56. 56.

    Chen A Klebanoff MA Basso O Pre-pregnancy body mass index change between pregnancies and preterm birth in the following pregnancyPaediatric and Perinatal Epidemiology2009 233207215

    Not in our library10.1111/j.1365-3016.2009.01029.x (opens in a new tab)

  57. 57.

    Driul L Cacciaguerra G Citossi A Martina MD Peressini L Marchesoni D Prepregnancy body mass index and adverse pregnancy outcomesArchives of Gynecology and Obstetrics2008 27812326

    Not in our library10.1007/s00404-007-0524-0 (opens in a new tab)

  58. 58.

    Johnson TS Rottier KJ Luellwitz A Kirby RS Maternal prepregnancy body mass index and delivery of a preterm infant in Missouri 1998–2000Public Health Nursing2009 261313

    Not in our library10.1111/j.1525-1446.2008.00750.x (opens in a new tab)

  59. 59.

    Kosa JL Guendelman S Pearl M Graham S Abrams B Kharrazi M The Association Between Pre-pregnancy BMI and Preterm Delivery in a Diverse Southern California Population of Working WomenMaternal and Child Health Journal2010 110

    Not in our library10.1007/s10995-010-0633-4 (opens in a new tab)

  60. 60.

    Murakami M Ohmichi M Takahashi T Shibata A Fukao A Morisaki N Kurachi H Prepregnancy body mass index as an important predictor of perinatal outcomes in JapaneseArchives of Gynecology and Obstetrics2005 2714311315

    Not in our library10.1007/s00404-004-0629-7 (opens in a new tab)

  61. 61.

    Ronnenberg AG Wang X Xing H Chen C Chen D Guang W Guang A Wang L Ryan L Xu X Low preconception body mass index is associated with birth outcome in a prospective cohort of Chinese womenJournal of Nutrition2003 133113449

    Not in our library10.1093/jn/133.11.3449 (opens in a new tab)

  62. 62.

    Salihu HM Mbah AK Alio AP Clayton HB Lynch O Low pre-pregnancy body mass index and risk of medically indicated versus spontaneous preterm singleton birthEuropean Journal of Obstetrics & Gynecology and Reproductive Biology2009 1442119123

    Not in our library10.1016/j.ejogrb.2009.02.047 (opens in a new tab)

  63. 63.

    Wise LA Palmer JR Heffner LJ Rosenberg L Prepregnancy body size, gestational weight gain, and risk of preterm birth in African-American womenEpidemiology2010 212243

    Not in our library10.1097/ede.0b013e3181cb61a9 (opens in a new tab)

  64. 64.

    Chen CW Tsai CY Sung FC Lee YY Lu TH Li CY Ko MC Adverse birth outcomes among pregnancies of teen mothers: age specific analysis of national data in TaiwanChild: Care, Health and Development2010 362232240

    Not in our library10.1111/j.1365-2214.2009.01039.x (opens in a new tab)

  65. 65.

    Gilboa SM Correa A Alverson CJ Use of spline regression in an analysis of maternal prepregnancy body mass index and adverse birth outcomes: does it tell us more than we already know?Annals of epidemiology2008 183196205

    Not in our library10.1016/j.annepidem.2007.09.005 (opens in a new tab)

  66. 66.

    Han YS Ha EH Park HS Kim YJ Lee SS Relationships between pregnancy outcomes, biochemical markers and pre-pregnancy body mass indexInternational Journal of Obesity2010

    Not in our library10.1038/ijo.2010.162 (opens in a new tab)

  67. 67.

    Nohr EA Vaeth M Baker JL Sorensen TIA Olsen J Rasmussen KM Combined associations of prepregnancy body mass index and gestational weight gain with the outcome of pregnancyAmerican Journal of Clinical Nutrition2008 8761750

    Not in our library10.1093/ajcn/87.6.1750 (opens in a new tab)

  68. 68.

    Watanabe H Inoue K Doi M Matsumoto M Ogasawara K Fukuoka H Nagai Y Risk factors for term small for gestational age infants in women with low prepregnancy body mass indexJournal of Obstetrics and Gynaecology Research2010 363506512

    Not in our library10.1111/j.1447-0756.2010.01170.x (opens in a new tab)

  69. 69.

    Frederick IO Williams MA Sales AE Martin DP Killien M Pre-pregnancy body mass index, gestational weight gain, and other maternal characteristics in relation to infant birth weightMaternal and Child Health Journal2008 125557567

    Not in our library10.1007/s10995-007-0276-2 (opens in a new tab)

  70. 70.

    Yekta Z Ayatollahi H Porali R Farzin A The effect of pre-pregnancy body mass index and gestational weight gain on pregnancy outcomes in urban care settings in Urmia-IranBMC Pregnancy and Childbirth2006 6115

    Not in our library10.1186/1471-2393-6-15 (opens in a new tab)

  71. 71.

    Chu SY Bachman DJ Callaghan WM Whitlock EP Dietz PM Berg CJ O'Keeffe-Rosetti M Bruce FC Hornbrook MC Association between obesity during pregnancy and increased use of health careNew England Journal of Medicine2008 358141444

    Not in our library10.1056/nejmoa0706786 (opens in a new tab)

  72. 72.

    Dietz PM Callaghan WM Morrow B Cogswell ME Population-based assessment of the risk of primary cesarean delivery due to excess prepregnancy weight among nulliparous women delivering term infantsMaternal and Child Health Journal2005 93237244

    Not in our library10.1007/s10995-005-0003-9 (opens in a new tab)

  73. 73.

    Getahun D Ananth CV Peltier MR Salihu HM Scorza WE Changes in prepregnancy body mass index between the first and second pregnancies and risk of large-for-gestational-age birthAmerican journal of obstetrics and gynecology2007 1966530

    Not in our library10.1016/j.ajog.2006.12.036 (opens in a new tab)

  74. 74.

    LaCoursiere D Bloebaum L Duncan JD Varner MW Population-based trends and correlates of maternal overweight and obesity, Utah 1991-2001American journal of obstetrics and gynecology2005 1923832839

    Not in our library10.1016/j.ajog.2004.11.034 (opens in a new tab)

  75. 75.

    Fortner RT Pekow P Solomon CG Markenson G Chasan-Taber L Prepregnancy body mass index, gestational weight gain, and risk of hypertensive pregnancy among Latina womenAmerican Journal of Obstetrics and Gynecology2009 2002167167

    Not in our library10.1016/j.ajog.2008.08.021 (opens in a new tab)

  76. 76.

    Saftlas AF Wang W Risch H Woolson R Hsu CD Bracken MB Prepregnancy body mass index and gestational weight gain as risk factors for preeclampsia and transient hypertensionAnnals of epidemiology2000 107475475

    Not in our library10.1016/s1047-2797(00)00167-8 (opens in a new tab)

  77. 77.

    Gilboa SM Correa A Botto LD Rasmussen SA Waller DK Hobbs CA Cleves MA Riehle-Colarusso TJ Association between prepregnancy body mass index and congenital heart defectsAmerican Journal of Obstetrics and Gynecology2010 202151

    Not in our library10.1016/j.ajog.2009.08.005 (opens in a new tab)

  78. 78.

    Oddy WH De Klerk NH Miller M Payne J Bower C Association of maternal pre pregnancy weight with birth defects: Evidence from a case–control study in Western AustraliaAustralian and New Zealand Journal of Obstetrics and Gynaecology2009 4911115

    Not in our library10.1111/j.1479-828x.2008.00934.x (opens in a new tab)

  79. 79.

    Waller DK Shaw GM Rasmussen SA Hobbs CA Canfield MA Siega-Riz AM Gallaway MS Correa A Prepregnancy obesity as a risk factor for structural birth defectsArchives of Pediatrics and Adolescent Medicine2007 1618745

    Not in our library10.1001/archpedi.161.8.745 (opens in a new tab)

  80. 80.

    Li Z Liu J Ye R Zhang L Pei L Zheng X Ren A Maternal prepregnancy body mass index and risk of neural tube defects: A population-based case-control study in Shanxi province, ChinaBirth Defects Research Part A: Clinical and Molecular Teratology2010

    Not in our library10.1002/bdra.20678 (opens in a new tab)

  81. 81.

    Waller DK Tita ATN Werler MM Mitchell AA Association between prepregnancy maternal body mass index and the risk of having an infant with a congenital diaphragmatic herniaBirth Defects Research Part A: Clinical and Molecular Teratology2003 6717376

    Not in our library10.1002/bdra.10003 (opens in a new tab)

  82. 82.

    Han Z Mulla S Beyene J Liao G McDonald SD Maternal underweight and the risk of preterm birth and low birth weight: a systematic review and meta-analysesInternational Journal of Epidemiology2011 40165

    Not in our library10.1093/ije/dyq195 (opens in a new tab)

  83. 83.

    Salihu HM Lynch ON Alio AP Mbah AK Kornosky JL Marty PJ Extreme maternal underweight and feto-infant morbidity outcomes: a population-based studyJournal of Maternal-Fetal and Neonatal Medicine2009 225428434

    Not in our library10.1080/14767050802385764 (opens in a new tab)

  84. 84.

    Jensen DM Damm P Sørensen B Mølsted-Pedersen L Westergaard JG Ovesen P Beck-Nielsen H Pregnancy outcome and prepregnancy body mass index in 2459 glucose-tolerant Danish womenAmerican journal of obstetrics and gynecology2003 1891239244

    Not in our library10.1067/mob.2003.441 (opens in a new tab)

  85. 85.

    Phithakwatchara N Titapant V The effect of pre-pregnancy weight on delivery outcome and birth weight in potential diabetic patients with normal screening for gestational diabetes mellitus in Siriraj HospitalJOURNAL-MEDICAL ASSOCIATION OF THAILAND2007 902229

    Not in our library

  86. 86.

    Barau G Robillard P Linear association between maternal pre pregnancy body mass index and risk of caesarean section in term deliveriesBJOG: An International Journal of Obstetrics & Gynaecology2006 1131011731177

    Not in our library10.1111/j.1471-0528.2006.01038.x (opens in a new tab)

  87. 87.

    Kaiser PS Kirby RS Obesity as a risk factor for cesarean in a low-risk populationObstetrics & Gynecology2001 97139

    Not in our library10.1016/s0029-7844(00)01078-4 (opens in a new tab)

  88. 88.

    Vahratian A Siega-Riz AM Savitz DA Zhang J Maternal pre-pregnancy overweight and obesity and the risk of cesarean delivery in nulliparous womenAnnals of epidemiology2005 157467474

    Not in our library10.1016/j.annepidem.2005.02.005 (opens in a new tab)

  89. 89.

    Frederick IO Rudra CB Miller RS Foster JC Williams MA Adult weight change, weight cycling, and prepregnancy obesity in relation to risk of preeclampsiaEpidemiology2006 174428

    Not in our library10.1097/01.ede.0000221028.33245.0b (opens in a new tab)

  90. 90.

    Glazer NL Hendrickson AF Schellenbaum GD Mueller BA Weight change and the risk of gestational diabetes in obese womenEpidemiology2004 156733

    Not in our library10.1097/01.ede.0000142151.16880.03 (opens in a new tab)

  91. 91.

    Gavard JA Artal R Effect of exercise on pregnancy outcomeClinical Obstetrics and Gynecology2008 512467

    Not in our library10.1097/grf.0b013e31816feb1d (opens in a new tab)

  92. 92.

    Birdsall KM Vyas S Khazaezadeh N Oteng Ntim E Maternal obesity: a review of interventionsInternational journal of clinical practice2009 633494507

    Not in our library10.1111/j.1742-1241.2008.01910.x (opens in a new tab)

  93. 93.

    Galtier F Raingeard I Renard E Boulot P Bringer J Optimizing the outcome of pregnancy in obese women: from pregestational to long-term managementDiabetes & metabolism2008 3411925

    Not in our library10.1016/j.diabet.2007.12.001 (opens in a new tab)

  94. 94.

    Fortner RT Pekow PS Whitcomb BW Sievert LL Markenson G Chasan-Taber L Physical Activity and Hypertensive Disorders of Pregnancy among Hispanic WomenMedicine & Science in Sports & Exercise2011 434639

    Not in our library10.1249/mss.0b013e3181f58d3e (opens in a new tab)

  95. 95.

    Martin CL Brunner Huber LR Physical Activity and Hypertensive Complications During Pregnancy: Findings from 2004 to 2006 North Carolina Pregnancy Risk Assessment Monitoring SystemBirth2010 373202210

    Not in our library10.1111/j.1523-536x.2010.00407.x (opens in a new tab)

  96. 96.

    Rudra CB Williams MA Lee I Perceived exertion during prepregnancy physical activity and preeclampsia riskMedicine & Science in Sports & Exercise2005 37111836

    Not in our library10.1249/01.mss.0000175862.41620.41 (opens in a new tab)

  97. 97.

    Rudra CB Sorensen TK Luthy DA Williams MA A prospective analysis of recreational physical activity and preeclampsia riskMedicine & Science in Sports & Exercise2008 4091581

    Not in our library10.1249/mss.0b013e31817cab1 (opens in a new tab)

  98. 98.

    Saftlas AF Logsden-Sackett N Wang W Woolson R Bracken MB Work, leisure-time physical activity, and risk of preeclampsia and gestational hypertensionAmerican journal of epidemiology2004 1608758

    Not in our library10.1093/aje/kwh277 (opens in a new tab)

  99. 99.

    Sorensen TK Williams MA Lee I Recreational physical activity during pregnancy and risk of preeclampsiaHypertension2003 4161273

    Not in our library10.1161/01.hyp.0000072270.82815.91 (opens in a new tab)

  100. 100.

    Dempsey JC Butler CL Sorensen TK Lee I A case-control study of maternal recreational physical activity and risk of gestational diabetes mellitus* 1Diabetes research and clinical practice2004 662203215

    Not in our library10.1016/j.diabres.2004.03.010 (opens in a new tab)

  101. 101.

    Dempsey JC Sorensen TK Williams MA Lee I Prospective study of gestational diabetes mellitus risk in relation to maternal recreational physical activity before and during pregnancyAmerican journal of epidemiology2004 1597663

    Not in our library10.1093/aje/kwh091 (opens in a new tab)

  102. 102.

    Oken E Ning Y Rifas-Shiman SL Radesky JS Rich-Edwards JW Gillman MW Associations of physical activity and inactivity before and during pregnancy with glucose toleranceObstetrics and gynecology2006 10851200

    Not in our library10.1097/01.aog.0000241088.60745.70 (opens in a new tab)

  103. 103.

    Rudra CB Williams MA Lee I Perceived exertion in physical activity and risk of gestational diabetes mellitusEpidemiology2006 17131

    Not in our library10.1097/01.ede.0000184474.33629.cd (opens in a new tab)

  104. 104.

    Tobias DK Zhang C van Dam RM Bowers K Hu FB Physical Activity Before and During Pregnancy and Risk of Gestational Diabetes MellitusDiabetes Care2011 341223

    Not in our library10.2337/dc10-1368 (opens in a new tab)

  105. 105.

    Zhang C Solomon CG Manson JAE Hu FB A prospective study of pregravid physical activity and sedentary behaviors in relation to the risk for gestational diabetes mellitusArchives of internal medicine2006 1665543

    Not in our library10.1001/archinte.166.5.543 (opens in a new tab)

  106. 106.

    Kinnunen TI Pasanen M Aittasalo M Fogelholm M Weiderpass E Luoto R Reducing postpartum weight retention – a pilot trial in primary health careNutrition Journal2007 6121

    Not in our library10.1186/1475-2891-6-21 (opens in a new tab)

  107. 107.

    Amorim Adegboye AR Linne YM Lourenco PMC Diet or exercise, or both, for weight reduction in women after childbirth2007 4status and date: Edited (no change to conclusions)

    Not in our library10.1002/14651858.cd005627.pub2 (opens in a new tab)

  108. 108.

    Black MM Hager ER Le K Anliker J Arteaga SS DiClemente C Gittelsohn J Magder L Papas M Snitker S Challenge! Health Promotion/Obesity Prevention Mentorship Model Among Urban, Black AdolescentsPediatrics2010 1262280

    Not in our library10.1542/peds.2009-1832 (opens in a new tab)

  109. 109.

    Eiben G Lissner L Health Hunters–an intervention to prevent overweight and obesity in young high-risk womenInternational journal of obesity2005 304691696

    Not in our library10.1038/sj.ijo.0803167 (opens in a new tab)

  110. 110.

    Faucher MA Mobley J A Community Intervention on Portion Control Aimed at Weight Loss in Low-Income Mexican American WomenJournal of Midwifery & Women's Health2010 5516064

    Not in our library10.1016/j.jmwh.2009.03.014 (opens in a new tab)

  111. 111.

    Gokee LaRose J Tate DF Gorin AA Wing RR Preventing Weight Gain in Young Adults:: A Randomized Controlled Pilot StudyAmerican journal of preventive medicine2010

    Not in our library10.1016/j.amepre.2010.03.011 (opens in a new tab)

  112. 112.

    Ostbye T Krause KM Lovelady CA Morey MC Bastian LA Peterson BL Swamy GK Brouwer RJN McBride CM Active Mothers Postpartum:: A Randomized Controlled Weight-Loss Intervention TrialAmerican journal of preventive medicine2009 373173180

    Not in our library10.1016/j.amepre.2009.05.016 (opens in a new tab)

  113. 113.

    Chang MW Nitzke S Brown R Design and Outcomes of a Mothers In Motion Behavioral Intervention Pilot StudyJournal of Nutrition Education and Behavior2010 423S1121

    Not in our library10.1016/j.jneb.2010.01.010 (opens in a new tab)

  114. 114.

    Harvey-Berino J West D Krukowski R Prewitt E VanBiervliet A Ashikaga T Skelly J Internet delivered behavioral obesity treatmentPreventive medicine2010

    Not in our library10.1016/j.ypmed.2010.04.018 (opens in a new tab)

  115. 115.

    Mediano MFF Barbosa JSO Moura AS Willett WC Sichieri R A randomized clinical trial of home-based exercise combined with a slight caloric restriction on obesity prevention among womenPreventive medicine2010

    Not in our library10.1016/j.ypmed.2010.07.012 (opens in a new tab)

  116. 116.

    Rock CL Flatt SW Sherwood NE Karanja N Pakiz B Thomson CA Effect of a Free Prepared Meal and Incentivized Weight Loss Program on Weight Loss and Weight Loss Maintenance in Obese and Overweight WomenJAMA: The Journal of the American Medical Association2010 304161803

    Not in our library10.1001/jama.2010.1503 (opens in a new tab)

  117. 117.

    Hall J Solehdin F Folic acid for the prevention of congenital anomaliesEuropean journal of pediatrics1998 1576445450

    Not in our library10.1007/s004310050850 (opens in a new tab)

  118. 118.

    Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research GroupLancet1991 338760131137

    Not in our library

  119. 119.

    Kirke PN Daly LE Elwood JH A randomised trial of low dose folic acid to prevent neural tube defects. The Irish Vitamin Study GroupBritish Medical Journal1992 67121442

    Not in our library10.1136/adc.67.12.1442 (opens in a new tab)

  120. 120.

    Laurence KM James N Miller MH Tennant GB Campbell H Double-blind randomised controlled trial of folate treatment before conception to prevent recurrence of neural-tube defectsBritish medical journal (Clinical research ed)1981 28262751509

    Not in our library10.1136/bmj.282.6275.1509 (opens in a new tab)

  121. 121.

    Suarez L Hendricks KA Cooper SP Sweeney AM Hardy RJ Larsen RD Neural tube defects among Mexican Americans living on the US-Mexico border: effects of folic acid and dietary folateAmerican journal of epidemiology2000 1521110171023

    Not in our library10.1093/aje/152.11.1017 (opens in a new tab)

  122. 122.

    Vergel RG Sanchez LR Heredero BL Rodriguez PL Martinez AJ Primary prevention of neural tube defects with folic acid supplementation: Cuban experiencePrenatal diagnosis1990 103149152

    Not in our library10.1002/pd.1970100303 (opens in a new tab)

  123. 123.

    Botto LD Olney RS Erickson JD Vitamin supplements and the risk for congenital anomalies other than neural tube defects2004 John Wiley & Sons1221

    Not in our library10.1002/ajmg.c.30004 (opens in a new tab)

  124. 124.

    Johnson KJ Alexander BH Doody MM Sigurdson AJ Linet MS Spector LG Hoffbeck RW Simon SL Weinstock RM Ross JA Childhood cancer in the offspring born in 1921–1984 to US radiologic technologistsBritish journal of cancer2008 993545550

    Not in our library10.1038/sj.bjc.6604516 (opens in a new tab)

  125. 125.

    Goh YI Bollano E Einarson TR Koren G Prenatal multivitamin supplementation and rates of congenital anomalies: a meta-analysisJ Obstet Gynaecol Can2006 288680689

    Not in our library10.1016/s1701-2163(16)32227-7 (opens in a new tab)

  126. 126.

    Badovinac RL Werler MM Williams PL Kelsey KT Hayes C Folic acid–containing supplement consumption during pregnancy and risk for oral clefts: A meta analysisBirth Defects Research Part A: Clinical and Molecular Teratology2007 791815

    Not in our library10.1002/bdra.20315 (opens in a new tab)

  127. 127.

    Suarez L Hendricks KA Cooper SP Sweeney AM Hardy RJ Larsen RD Neural tube defects among Mexican Americans living on the US-Mexico border: effects of folic acid and dietary folateAmerican journal of epidemiology2000 152111017

    Not in our library10.1093/aje/152.11.1017 (opens in a new tab)

  128. 128.

    Berry RJ Li Z Erickson JD Li S Moore CA Wang H Mulinare J Zhao P Wong LYC Gindler J Prevention of neural-tube defects with folic acid in ChinaNew England Journal of Medicine1999 341201485

    Not in our library10.1056/nejm199911113412001 (opens in a new tab)

  129. 129.

    Bower C Stanley FJ Periconceptional vitamin supplementation and neural tube defects; evidence from a case-control study in Western Australia and a review of recent publicationsJournal of Epidemiology and Community Health1992 462157

    Not in our library10.1136/jech.46.2.157 (opens in a new tab)

  130. 130.

    Ulrich M Kristoffersen K Rolschau J Grinsted P Schaumburg E Foged N The influence of folic acid supplement on the outcome of pregnancies in the county of Funen in Denmark. Part II. Congenital anomalies. A randomised studyEur J Obstet Gynecol Reprod Biol1999 872111113discussion 103-114

    Not in our library

  131. 131.

    Central Technical Co-ordinating Unit, ICMRCentral Technical Co-ordinating Unit IMulticentric study of efficacy of periconceptional folic acid containing vitamin supplementation in prevention of open neural tube defects from IndiaIndian J Med Res2000 112206211

    Not in our library

  132. 132.

    Smithells RW Sheppard S Schorah CJ Seller MJ Nevin NC Harris R Read AP Fielding DW Apparent prevention of neural tube defects by periconceptional vitamin supplementationArchives of disease in childhood1981 5612911

    Not in our library10.1136/adc.56.12.911 (opens in a new tab)

  133. 133.

    Chen G Song X Ji Y Zhang L Pei L Chen J Liu J Li C Zheng X Prevention of NTDs with periconceptional multivitamin supplementation containing folic acid in ChinaBirth Defects Research Part A Clinical and Molecular Teratology2008 828592596

    Not in our library10.1002/bdra.20471 (opens in a new tab)

  134. 134.

    Czeizel AE Reduction of urinary tract and cardiovascular defects by periconceptional multivitamin supplementationAmerican Journal of Medical Genetics Part A1996 622179183

    Not in our library10.1002/(sici)1096-8628(19960315)62:2<179::aid-ajmg12>3.0.co;2-l (opens in a new tab)

  135. 135.

    Czeizel AE Dobó M Vargha P Hungarian cohort controlled trial of periconceptional multivitamin supplementation shows a reduction in certain congenital abnormalitiesBirth Defects Research Part A Clinical and Molecular Teratology2004 7011853861

    Not in our library10.1002/bdra.20086 (opens in a new tab)

  136. 136.

    Mulinare J Cordero JF Erickson JD Berry RJ Periconceptional use of multivitamins and the occurrence of neural tube defectsJAMA1988 260213141

    Not in our library

  137. 137.

    Shaw GM Schaffer D Velie EM Morland K Harris JA Periconceptional vitamin use, dietary folate, and the occurrence of neural tube defectsEpidemiology1995 63219226

    Not in our library10.1097/00001648-199505000-00005 (opens in a new tab)

  138. 138.

    Werler MM Shapiro S Mitchell AA Periconceptional folic acid exposure and risk of occurrent neural tube defectsJAMA1993 269101257

    Not in our library

  139. 139.

    Bower C Miller M Payne J Serna P Folate intake and the primary prevention of non neural birth defectsAustralian and New Zealand Journal of Public Health2006 303258261

    Not in our library10.1111/j.1467-842x.2006.tb00867.x (opens in a new tab)

  140. 140.

    Czeizel AE Timar L Sarkozi A Dose-dependent effect of folic acid on the prevention of orofacial cleftsPediatrics1999 1046e66

    Not in our library10.1542/peds.104.6.e66 (opens in a new tab)

  141. 141.

    Hayes C Werter MM Willett WC Mitchell AA Case-control study of periconceptional folic acid supplementation and oral cleftsAmerican journal of epidemiology1996 143121229

    Not in our library10.1093/oxfordjournals.aje.a008710 (opens in a new tab)

  142. 142.

    Johnson CY Little J Folate intake, markers of folate status and oral clefts: is the evidence converging?International journal of epidemiology2008 3751041

    Not in our library10.1093/ije/dyn098 (opens in a new tab)

  143. 143.

    Itikala PR Watkins ML Mulinare J Moore CA Liu Y Maternal multivitamin use and orofacial clefts in offspringTeratology2001 6327986

    Not in our library10.1002/1096-9926(200102)63:2<79::aid-tera1013>3.0.co;2-3 (opens in a new tab)

  144. 144.

    Van Beynum IM Kapusta L Bakker MK Den Heijer M Blom HJ de Walle HEK Protective effect of periconceptional folic acid supplements on the risk of congenital heart defects: a registry-based case-control study in the northern NetherlandsEuropean heart journal2009

    Not in our library10.1093/eurheartj/ehp479 (opens in a new tab)

  145. 145.

    Scanlon KS Ferencz C Loffredo CA Wilson PD Correa-Villaseñor A Khoury MJ Willett WC Preconceptional folate intake and malformations of the cardiac outflow tractEpidemiology1998 9195

    Not in our library

  146. 146.

    Botto LD Khoury MJ Mulinare J Erickson JD Periconceptional multivitamin use and the occurrence of conotruncal heart defects: results from a population-based, case-control studyPediatrics1996 985911

    Not in our library

  147. 147.

    Li DK Daling JR Mueller BA Hickok DE Fantel AG Weiss NS Periconceptional multivitamin use in relation to the risk of congenital urinary tract anomaliesEpidemiology1995 63212

    Not in our library10.1097/00001648-199505000-00004 (opens in a new tab)

  148. 148.

    Yang Q Khoury MJ Olney RS Mulinare J Does periconceptional multivitamin use reduce the risk for limb deficiency in offspring?Epidemiology1997 82157161

    Not in our library10.1097/00001648-199703000-00006 (opens in a new tab)

  149. 149.

    Bitsko RH Reefhuis J Romitti PA Moore CA Honein MA Periconceptional consumption of vitamins containing folic acid and risk for multiple congenital anomaliesAmerican Journal of Medical Genetics Part A2007 1432023972405

    Not in our library10.1002/ajmg.a.31950 (opens in a new tab)

  150. 150.

    Czeizel AE Medveczky E Periconceptional multivitamin supplementation and multimalformed offspringObstetrics & Gynecology2003 10261255

    Not in our library10.1016/j.obstetgynecol.2003.06.001 (opens in a new tab)

  151. 151.

    Khoury MJ Shaw GM Moore CA Lammer EJ Mulinare J Does periconceptional multivitamin use reduce the risk of neural tube defects associated with other birth defects? Data from two population-based case-control studiesAmerican Journal of Medical Genetics Part A1996 6113036

    Not in our library10.1002/(sici)1096-8628(19960102)61:1<30::aid-ajmg6>3.0.co;2-0 (opens in a new tab)

  152. 152.

    Shaw GM Croen LA Todoroff K Tolarova MM Periconceptional intake of vitamin supplements and risk of multiple congenital anomaliesAmerican journal of medical genetics2000 933188193

    Not in our library10.1002/1096-8628(20000731)93:3<188::aid-ajmg5>3.0.co;2-z (opens in a new tab)

  153. 153.

    Catov JM Bodnar LM Ness RB Markovic N Roberts JM Association of periconceptional multivitamin use and risk of preterm or small-for-gestational-age birthsAmerican journal of epidemiology2007 1663296

    Not in our library10.1093/aje/kwm071 (opens in a new tab)

  154. 154.

    Czeizel AE Dudas I Metneki J Pregnancy outcomes in a randomised controlled trial of periconceptional multivitamin supplementationArchives of Gynecology and Obstetrics1994 2553131139

    Not in our library10.1007/bf02390940 (opens in a new tab)

  155. 155.

    Bodnar LM Tang G Ness RB Harger G Roberts JM Periconceptional multivitamin use reduces the risk of preeclampsiaAmerican journal of epidemiology2006 1645470

    Not in our library10.1093/aje/kwj218 (opens in a new tab)

  156. 156.

    Catov JM Nohr EA Bodnar LM Knudson VK Olsen SF Olsen J Association of periconceptional multivitamin use with reduced risk of preeclampsia among normal-weight women in the Danish National Birth CohortAmerican journal of epidemiology2009 169111304

    Not in our library10.1093/aje/kwp052 (opens in a new tab)

  157. 157.

    Calvo EB Biglieri A Impact of folic acid fortification on women nutritional status and on the prevalence of neural tube defectsArchivos argentinos de pediatría2008 106492498

    Not in our library10.1590/s0325-00752008000600004 (opens in a new tab)

  158. 158.

    Mersereau P Kilker K Carter H Fassett E Williams J Flores A Prue C Williams L Mai C Mulinare J Spina bifida and anencephaly before and after folic acid mandate—United States, 1995–1996 and 1999–2000Morbidity and Mortality Weekly Report2004 5317362365

    Not in our library

  159. 159.

    De Wals P Rusen ID Lee NS Morin P Niyonsenga T Trend in prevalence of neural tube defects in QuebecBirth Defects Research Part A: Clinical and Molecular Teratology2003 6711919923

    Not in our library10.1002/bdra.10124 (opens in a new tab)

  160. 160.

    Gucciardi E Pietrusiak MA Reynolds DL Rouleau J Incidence of neural tube defects in Ontario, 1986-1999Canadian Medical Association Journal2002 1673237

    Not in our library

  161. 161.

    Honein MA Paulozzi LJ Mathews TJ Erickson JD Wong LYC Impact of folic acid fortification of the US food supply on the occurrence of neural tube defectsJama2001 285232981

    Not in our library10.1001/jama.285.23.2981 (opens in a new tab)

  162. 162.

    Liu S West R Randell E Longerich L O'Connor KS Scott H Crowley M Lam A Prabhakaran V McCourt C A comprehensive evaluation of food fortification with folic acid for the primary prevention of neural tube defectsBMC Pregnancy and Childbirth2004 4120

    Not in our library10.1186/1471-2393-4-20 (opens in a new tab)

  163. 163.

    López Camelo JS Orioli IM Dutra MG Nazer Herrera J Rivera N Ojeda ME Canessa A Wettig E Fontannaz AM Mellado C Reduction of birth prevalence rates of neural tube defects after folic acid fortification in ChileAmerican Journal of Medical Genetics Part A2005 1352120125

    Not in our library10.1002/ajmg.a.30651 (opens in a new tab)

  164. 164.

    Persad VL Van den Hof MC Dube JM Zimmer P Incidence of open neural tube defects in Nova Scotia after folic acid fortificationCanadian Medical Association Journal2002 1673241

    Not in our library

  165. 165.

    Ray JG Meier C Vermeulen MJ Boss S Wyatt PR Cole DEC Association of neural tube defects and folic acid food fortification in CanadaThe Lancet2002 360935020472048

    Not in our library10.1016/s0140-6736(02)11994-5 (opens in a new tab)

  166. 166.

    Sayed AR Bourne D Pattinson R Nixon J Henderson B Decline in the prevalence of neural tube defects following folic acid fortification and its cost benefit in South AfricaBirth Defects Research Part A: Clinical and Molecular Teratology2008 824211216

    Not in our library10.1002/bdra.20442 (opens in a new tab)

  167. 167.

    Simmons CJ Mosley BS Fulton Bond CA Hobbs CA Birth defects in Arkansas: Is folic acid fortification making a difference?Birth Defects Research Part A: Clinical and Molecular Teratology2004 709559564

    Not in our library10.1002/bdra.20063 (opens in a new tab)

  168. 168.

    Williams LJ Mai CT Edmonds LD Shaw GM Kirby RS Hobbs CA Sever LE Miller LA Meaney FJ Levitt M Prevalence of spina bifida and anencephaly during the transition to mandatory folic acid fortification in the United StatesTeratology2002 6613339

    Not in our library10.1002/tera.10060 (opens in a new tab)

  169. 169.

    Williams LJ Rasmussen SA Flores A Kirby RS Edmonds LD Decline in the prevalence of spina bifida and anencephaly by race/ethnicity: 1995-2002Pediatrics2005 1163580

    Not in our library10.1542/peds.2005-0592 (opens in a new tab)

  170. 170.

    Li Z Gindler J Wang H Berry RJ Li S Correa A Zheng J Erickson JD Wang Y Folic acid supplements during early pregnancy and likelihood of multiple births: a population-based cohort studyThe Lancet2003 3619355380384

    Not in our library10.1016/s0140-6736(03)12390-2 (opens in a new tab)

  171. 171.

    Vollset SE Gjessing HK Tandberg A Rønning T Irgens LM Baste V Nilsen RM Daltveit AK Folate supplementation and twin pregnanciesEpidemiology2005 162201

    Not in our library10.1097/01.ede.0000152914.84962.13 (opens in a new tab)

  172. 172.

    Lawrence JM Watkins ML Chiu V Erickson JD Petitti DB Food fortification with folic acid and rate of multiple births, 1994–2000Birth Defects Research Part A: Clinical and Molecular Teratology2004 7012948952

    Not in our library10.1002/bdra.20088 (opens in a new tab)

  173. 173.

    Shaw GM Carmichael SL Nelson V Selvin S Schaffer DM Food fortification with folic acid and twinning among California infantsAmerican Journal of Medical Genetics Part A2003 1192137140

    Not in our library10.1002/ajmg.a.20145 (opens in a new tab)

  174. 174.

    Signore C Mills JL Cox C Trumble AC Effects of folic acid fortification on twin gestation ratesObstetrics & Gynecology2005 1054757

    Not in our library10.1097/01.aog.0000154886.40318.5e (opens in a new tab)

  175. 175.

    Chevrier C Perret C Bahuau M Zhu H Nelva A Herman C Francannet C Robert Gnansia E Finnell RH Cordier S Fetal and maternal MTHFR C677T genotype, maternal folate intake and the risk of nonsyndromic oral cleftsAmerican Journal of Medical Genetics Part A2007 1433248257

    Not in our library10.1002/ajmg.a.31462 (opens in a new tab)

  176. 176.

    Little J Gilmour M Mossey PA FitzPatrick D Cardy A Clayton-Smith J Fryer AE Folate and Clefts of the Lip and Palate-A UK-Based Case-Control Study: Part I: Dietary and Supplemental FolateThe Cleft Palate-Craniofacial Journal2008 454420427

    Not in our library10.1597/06-150.1 (opens in a new tab)

  177. 177.

    Shaw GM Carmichael SL Laurent C Rasmussen SA Maternal nutrient intakes and risk of orofacial cleftsEpidemiology2006 173285

    Not in our library10.1097/01.ede.0000208348.30012.35 (opens in a new tab)

  178. 178.

    van Rooij I Swinkels DW Blom HJ Merkus H Steegers-Theunissen RPM Vitamin and homocysteine status of mothers and infants and the risk of nonsyndromic orofacial clefts* 1American Journal of Obstetrics and Gynecology2003 189411551160

    Not in our library10.1067/s0002-9378(03)00592-1 (opens in a new tab)

  179. 179.

    Wilcox AJ Lie RT Solvoll K Taylor J McConnaughey DR Åbyholm F Vindenes H Vollset SE Drevon CA Folic acid supplements and risk of facial clefts: national population based case-control studyBMJ2007 3347591464

    Not in our library10.1136/bmj.39079.618287.0b (opens in a new tab)

  180. 180.

    De Walle HEK De Jong Van Den Berg LTW Insufficient folic acid intake in the Netherlands: what about the future?Teratology2002 6614043

    Not in our library10.1002/tera.10078 (opens in a new tab)

  181. 181.

    Kannan S Menotti E Scherer HK Dickinson J Larson K Folic acid and the prevention of neural tube defects: A survey of awareness among Latina women of childbearing age residing in southeast MichiganHealth promotion practice2007 8160

    Not in our library10.1177/1524839905278934 (opens in a new tab)

  182. 182.

    Kari JA Bardisi ES Baitalmal RM Ageely GA Folic acid awareness among female college students: neural tube defects preventionSaudi Med J2008 291217491751

    Not in our library

  183. 183.

    Sillender M Pring DW How effective was the Health Education Authority s folic acid campaign?Journal of Obstetrics and Gynaecology2000 203271276

    Not in our library10.1080/01443610050009593 (opens in a new tab)

  184. 184.

    Der Pal de Bruin V The Dutch ‘Folic Acid Campaign’–have the goals been achieved?Paediatric and Perinatal Epidemiology2000 142111117

    Not in our library10.1046/j.1365-3016.2000.00251.x (opens in a new tab)

  185. 185.

    Chan A Pickering J Haan EA Netting M Burford A Johnson A Keane RJ " Folate before pregnancy": the impact on women and health professionals of a population-based health promotion campaign in South AustraliaObstetrical & Gynecological Survey2002 5718

    Not in our library10.5694/j.1326-5377.2001.tb143471.x (opens in a new tab)

  186. 186.

    Pastuszak A Bhatia D Okotore B Koren G Preconception counseling and women's compliance with folic acid supplementationCanadian Family Physician1999 452053

    Not in our library

  187. 187.

    Stevenson RE Allen WP Pai GS Best R Seaver LH Dean J Thompson S Decline in prevalence of neural tube defects in a high-risk region of the United StatesPediatrics2000 1064677

    Not in our library10.1542/peds.106.4.677 (opens in a new tab)

  188. 188.

    Robbins JM Cleves MA Collins HB Andrews N Smith LN Hobbs CA Randomized trial of a physician-based intervention to increase the use of folic acid supplements among womenAmerican Journal of Obstetrics and Gynecology2005 192411261132

    Not in our library10.1016/j.ajog.2004.10.620 (opens in a new tab)

  189. 189.

    Watson MJ Watson LF Bell RJ Halliday JL Burford N Brennecke SP A randomized community intervention trial to increase awareness and knowledge of the role of periconceptional folate in women of child-bearing ageHealth Expect1999 24255265

    Not in our library10.1046/j.1369-6513.1999.00064.x (opens in a new tab)

  190. 190.

    Watson M Watson L Bell R Halliday J The increasing knowledge of the role of periconceptional folate in Victorian women of child-bearing age: follow-up of a randomised community intervention trialAust N Z J Public Health2001 255389395

    Not in our library

  191. 191.

    Chacko MR Anding R Kozinetz CA Grover JL Smith PB Neural tube defects: knowledge and preconceptional prevention practices in minority young womenPediatrics2003 1123536

    Not in our library10.1542/peds.112.3.536 (opens in a new tab)

  192. 192.

    Hauser KW Lilly CM Frías JL Florida health care providers' knowledge of folic acid for the prevention of neural tube defectsSouthern medical journal2004 975437

    Not in our library10.1097/00007611-200405000-00004 (opens in a new tab)

  193. 193.

    Watkins ML Brustrom J Schulman J Effectiveness of a free folic acid supplement program in family planning clinicsBirth Defects Research Clinical and Molecular Teratology2004 706403407

    Not in our library10.1002/bdra.20035 (opens in a new tab)

  194. 194.

    Lawrence JM Watkins ML Ershoff D Petitti DB Chiu V Postlethwaite D Erickson JD Design and evaluation of interventions promoting periconceptional multivitamin useAmerican Journal of Preventive Medicine2003 2511724

    Not in our library10.1016/s0749-3797(03)00097-7 (opens in a new tab)

  195. 195.

    Egen V Hasford J Prevention of neural tube defects: effect of an intervention aimed at implementing the official recommendationsSozial-und Präventivmedizin/Social and Preventive Medicine2003 4812432

    Not in our library10.1007/s000380300003 (opens in a new tab)

  196. 196.

    Mullenix A Reaching Women and Health Care Providers with Women’s Wellness MessagesNC Med J2009 705

    Not in our library

  197. 197.

    Baro L Martinez-Ferez A Rodriguez C Valero A Fonolla J Lucena A Jimenez J Boza JJ Lopez-Huertas E The administration of a multivitamin/mineral fortified dairy product improves folate status and reduces plasma homocysteine concentration in women of reproductive ageInternational journal for vitamin and nutrition research2004 743234240

    Not in our library10.1024/0300-9831.74.3.234 (opens in a new tab)

  198. 198.

    de Weerd S Thomas CMG Cikot RJLM Steegers-Theunissen RPM de Boo TM Steegers EAP Preconception counseling improves folate status of women planning pregnancyObstetrics & Gynecology2002 99145

    Not in our library10.1016/s0029-7844(01)01573-3 (opens in a new tab)

  199. 199.

    Muggli EE Halliday JL Folic acid and risk of twinning: a systematic review of the recent literature, July 1994 to July 2006Medical Journal of Australia2007 1865243

    Not in our library10.5694/j.1326-5377.2007.tb00882.x (opens in a new tab)

  200. 200.

    Shaw GM O'Malley CD Wasserman CR Tolarova MM Lammer EJ Maternal periconceptional use of multivitamins and reduced risk for conotruncal heart defects and limb deficiencies among offspringAmerican journal of medical genetics1995 594536545

    Not in our library10.1002/ajmg.1320590428 (opens in a new tab)

  201. 201.

    Wang Y Jun PEIL Ming SX Gong C Ying ZX Impact of Periconceptional Multi-micronutrient Supplementation on Gestation: A Population-based StudyBiomed Environ Sci2013 2612331

    Not in our library10.3967/0895-3988.2013.01.003 (opens in a new tab)

  202. 202.

    Ronnenberg AG Wood RJ Wang X Xing H Chen C Chen D Guang W Huang A Wang L Xu X Preconception hemoglobin and ferritin concentrations are associated with pregnancy outcome in a prospective cohort of Chinese womenJournal of Nutrition2004 134102586

    Not in our library10.1093/jn/134.10.2586 (opens in a new tab)

  203. 203.
  204. 204.

    Peña-Rosas JP V F Effects and safety of preventive oral iron or iron+folic acid supplementation for women during pregnancy2009

    Not in our library10.1002/14651858.cd004736.pub3 (opens in a new tab)

  205. 205.

    Berger J T H Cavalli-Sforza T Smitasiri S Khan NC Milani S Community mobilization and social marketing to promote weekly iron-folic acid supplementation in women of reproductive age in Vietnam: impact on anemia and iron status2005

    Not in our library10.1301/nr.2005.dec.s95-s108 (opens in a new tab)

  206. 206.

    Angeles-Agdeppa I P L Ramos AC Etorma UM Cavalli-Sforza T Milani S Government-Industry Partnership in Weekly Iron-Folic Acid Supplementation for Women of Reproductive Age in the Philippines2005

    Not in our library10.1301/nr.2005.dec.s116-s125 (opens in a new tab)

  207. 207.

    Khambalia AZ O'Connor DL Macarthur C Dupuis A Zlotkin SH Periconceptional iron supplementation does not reduce anemia or improve iron status among pregnant women in rural BangladeshThe American journal of clinical nutrition2009 90512951302

    Not in our library10.3945/ajcn.2009.28350 (opens in a new tab)

  208. 208.

    Casey GJ J D Phuc TQ Tinh TT Tho DH Long-term weekly iron-folic acid and de-worming is associated with stabilised haemoglobin and increasing iron stores in non-pregnant women in Vietnam2010

    Not in our library10.1371/journal.pone.0015691 (opens in a new tab)

  209. 209.

    Passerini L C G Biggs BA Cong DT Phu LB Phuc TQ Carone M Montresor A Increased birth weight associated with regular pre-pregnancy deworming and weekly iron-folic acid supplementation for Vietnamese women2012

    Not in our library10.1371/journal.pntd.0001608 (opens in a new tab)

  210. 210.

    Vir SC S N Nigam AK Jain R Weekly iron and folic acid supplementation with counseling reduces anemia in adolescent girls2008

    Not in our library10.1177/156482650802900304 (opens in a new tab)

  211. 211.

    Mendez MA Monteiro CA Popkin BM Overweight exceeds underweight among women in most developing countriesAmerican Journal of Clinical Nutrition2005 813714

    Not in our library10.1093/ajcn/81.3.714 (opens in a new tab)

  212. 212.

    Han YW Oral Health and Adverse Pregnancy Outcomes–What’s Next?Journal of Dental Research2011 903289

    Not in our library10.1177/0022034510381905 (opens in a new tab)

  213. 213.

    O'Brien TE Ray JG Chan WS Maternal body mass index and the risk of preeclampsia: a systematic overviewEpidemiology2003 143368

    Not in our library10.1097/00001648-200305000-00020 (opens in a new tab)

  214. 214.

    Torloni MR Betrán AP Horta BL Nakamura MU Atallah AN Moron AF Valente O Prepregnancy BMI and the risk of gestational diabetes: a systematic review of the literature with meta analysisObesity Reviews2009 102194203

    Not in our library10.1111/j.1467-789x.2008.00541.x (opens in a new tab)

  215. 215.

    Poobalan AS Aucott LS Gurung T Smith WCS Bhattacharya S Obesity as an independent risk factor for elective and emergency caesarean delivery in nulliparous women–systematic review and meta analysis of cohort studiesObesity Reviews2009 1012835

    Not in our library10.1111/j.1467-789x.2008.00537.x (opens in a new tab)

  216. 216.

    Nuthalapaty FS Rouse DJ The impact of obesity on obstetrical practice and outcomeClinical obstetrics and gynecology2004 474898

    Not in our library10.1097/01.grf.0000135358.34673.48 (opens in a new tab)

  217. 217.

    WHOConsultation on Antiretroviral Treatment for Prevention of HIV Transmission. Meeting Report2009 Geneva, Switzerland

    Not in our library

  218. 218.

    Vrebosch L B S Vansant Maternal and neonatal outcome after laparoscopic adjustable gastric banding: a systematic2012

    Not in our library10.1007/s11695-012-0740-y (opens in a new tab)

  219. 219.

    Cornel MC Erickson JD Comparison of national policies on periconceptional use of folic acid to prevent spina bifida and anencephaly (SBA)Teratology1997 552134137

    Not in our library10.1002/(sici)1096-9926(199702)55:2<134::aid-tera3>3.0.co;2-3 (opens in a new tab)

  220. 220.

    Bener A Al Maadid MGA Al-Bast DAE Al-Marri S Maternal knowledge, attitude and practice on folic acid intake among Arabian Qatari womenReproductive Toxicology2005 2112125

    Not in our library10.1016/j.reprotox.2005.07.004 (opens in a new tab)

  221. 221.

    Brough L Rees GA Crawford MA Dorman EK Social and ethnic differences in folic acid use preconception and during early pregnancy in the UK: effect on maternal folate statusJournal of human nutrition and dietetics2009 222100107

    Not in our library10.1111/j.1365-277x.2008.00936.x (opens in a new tab)

  222. 222.

    Coll O Pisa S Palacio M Quintó L Cararach V Awareness of the use of folic acid to prevent neural tube defects in a Mediterranean areaEuropean Journal of Obstetrics & Gynecology and Reproductive Biology2004 1152173177

    Not in our library10.1016/j.ejogrb.2003.12.009 (opens in a new tab)

  223. 223.

    CDCThe importance of preconception care in the continuum of women's health careObstet Gynecol Clin North Am2005 1063665666

    Not in our library10.1097/00006250-200509000-00052 (opens in a new tab)

  224. 224.

    De Walle HE Van der Pal KM Periconceptional folic acid in The Netherlands in 1995. Socioeconomic differencesJournal of epidemiology and community health1998 5212826

    Not in our library10.1136/jech.52.12.826 (opens in a new tab)

  225. 225.

    Howell SR Barnett AG Underwood MR The use of pre-conceptional folic acid as an indicator of uptake of a health message amongst white and Bangladeshi women in Tower Hamlets, east LondonFamily Practice2001 183300

    Not in our library10.1093/fampra/18.3.300 (opens in a new tab)

  226. 226.

    Nawapun K Phupong V Awareness of the benefits of folic acid and prevalence of the use of folic acid supplements to prevent neural tube defects among Thai womenArchives of Gynecology and Obstetrics2007 27615357

    Not in our library10.1007/s00404-006-0305-1 (opens in a new tab)

  227. 227.

    Tamim H Harrison G Atoui M Mumtaz G El-Kak F Seoud M Yunis K Preconceptional folic acid supplement use in LebanonPublic health nutrition2009 1205687692

    Not in our library10.1017/s136898000800298x (opens in a new tab)

  228. 228.

    Paudel P W K Silpakar SK Awareness of periconceptional folic acid supplementation among Nepalese women of childbearing age: a cross-sectional study2012

    Not in our library10.1016/j.ypmed.2012.09.001 (opens in a new tab)

  229. 229.

    Stockley L Lund V Use of folic acid supplements, particularly by low-income and young women: a series of systematic reviews to inform public health policy in the UKPublic health nutrition2008 1108807821

    Not in our library10.1017/s1368980008002346 (opens in a new tab)

  230. 230.

    Botto LD Lisi A Bower C Canfield MA Dattani N De Vigan C De Walle H Erickson DJ Halliday J Irgens LM Trends of selected malformations in relation to folic acid recommendations and fortification: an international assessmentBirth Defects Research Part A: Clinical and Molecular Teratology2006 7610693705

    Not in our library10.1002/bdra.20307 (opens in a new tab)

  231. 231.

    Oakley GP Folate deficiency is an“imminent health hazard” causing a worldwide birth defects epidemicBirth Defects Research Part A Clinical and Molecular Teratology2003 6711903904

    Not in our library10.1002/bdra.10141 (opens in a new tab)

  232. 232.

    W NJ Folic acid and the prevention of neural-tube defects2004

    Not in our library

  233. 233.

    Locksmith GJ Duff P Preventing neural tube defects: the importance of periconceptional folic acid supplementsObstetrics & Gynecology1998 9161027

    Not in our library10.1016/s0029-7844(98)00060-x (opens in a new tab)

  234. 234.

    Kondo A Kamihira O Ozawa H Neural tube defects: Prevalence, etiology and preventionInternational Journal of Urology2009 1614957

    Not in our library10.1111/j.1442-2042.2008.02163.x (opens in a new tab)

  235. 235.

    Holzgreve W P K Koletzko B Adding folate to the contraceptive pill: a new concept for the prevention of neural tube defects.J Matern Fetal Neonata2012

    Not in our library10.3109/14767058.2011.648672 (opens in a new tab)

  236. 236.

    Van Thuy P Berger J Nakanishi Y Khan NC Lynch S Dixon P The use of NaFeEDTA-fortified fish sauce is an effective tool for controlling iron deficiency in women of childbearing age in rural VietnamThe Journal of nutrition2005 1351125962601

    Not in our library10.1093/jn/135.11.2596 (opens in a new tab)

  237. 237.

    Sadighi J Mohammad K Sheikholeslam R Amirkhani MA Torabi P Salehi F Abdolahi Z Anaemia control: lessons from the flour fortification programmePublic health2009 12312794799

    Not in our library10.1016/j.puhe.2009.09.024 (opens in a new tab)

  238. 238.

    Hotz C Porcayo M Onofre Gn García-Guerra A Elliott T Jankowski S Greiner T Efficacy of iron-fortified Ultra Rice in improving the iron status of women in MexicoFood & Nutrition Bulletin2008 292140149

    Not in our library10.1177/156482650802900208 (opens in a new tab)

  239. 239.

    Blanco-Rojo R Perez-Granados AM Toxqui L Gonzalez-Vizcayno C Delgado MA Vaquero MP Efficacy of a microencapsulated iron pyrophosphate-fortified fruit juice: a randomised, double-blind, placebo-controlled study in Spanish iron-deficient womenBritish Journal of Nutrition2011 105111652

    Not in our library10.1017/s0007114510005490 (opens in a new tab)

  240. 240.

    Biebinger R Zimmermann MB Al-Hooti SN Al-Hamed N Al-Salem E Zafar T Kabir Y Petry N Hurrell RF Efficacy of wheat-based biscuits fortified with microcapsules containing ferrous sulfate and potassium iodate or a new hydrogen-reduced elemental iron: a randomised, double-blind, controlled trial in Kuwaiti womenBritish Journal of Nutrition2009 1020913621369

    Not in our library10.1017/s0007114509990353 (opens in a new tab)

  241. 241.

    Bhutta ZA S R Global nutrition epidemiology and trends2012

    Not in our library10.1159/000345167 (opens in a new tab)

  242. 242.

    Dean SV Lassi ZS Imam AM Bhutta ZA Preconception care: promoting reproductive planningReproductive Health2014

    Not in our library10.1186/1742-4755-11-s3-s2 (opens in a new tab)

Cited by papers we hold 6

Questions about this paper

We email you if it is retracted, withdrawn, corrected or flagged.

Reads

Read by people on this page

None yet.

Checked or read by AI through naulon

None yet.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.

Are you an author?

Is this your paper?

Claim it to add your note and be paid when agents cite it. Free.