Skip to main content
Top
Published in: BMC Pregnancy and Childbirth 1/2014

Open Access 01-12-2014 | Study protocol

Prevention of congenital malformations and other adverse pregnancy outcomes with 4.0 mg of folic acid: community-based randomized clinical trial in Italy and the Netherlands

Authors: Renata Bortolus, Fenneke Blom, Francesca Filippini, Mireille NM van Poppel, Emanuele Leoncini, Denhard J de Smit, Pier Paolo Benetollo, Martina C Cornel, Hermien EK de Walle, Pierpaolo Mastroiacovo

Published in: BMC Pregnancy and Childbirth | Issue 1/2014

Login to get access

Abstract

Background

In 2010 a Cochrane review confirmed that folic acid (FA) supplementation prevents the first- and second-time occurrence of neural tube defects (NTDs). At present some evidence from observational studies supports the hypothesis that FA supplementation can reduce the risk of all congenital malformations (CMs) or the risk of a specific and selected group of them, namely cardiac defects and oral clefts. Furthermore, the effects on the prevention of prematurity, foetal growth retardation and pre-eclampsia are unclear.
Although the most common recommendation is to take 0.4 mg/day, the problem of the most appropriate dose of FA is still open.
The aim of this project is to assess the effect a higher dose of peri-conceptional FA supplementation on reducing the occurrence of all CMs. Other aims include the promotion of pre-conceptional counselling, comparing rates of selected CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age, abruptio placentae.

Methods/Design

This project is a joint effort by research groups in Italy and the Netherlands. Women of childbearing age, who intend to become pregnant within 12 months are eligible for the studies. Women are randomly assigned to receive 4 mg of FA (treatment in study) or 0.4 mg of FA (referent treatment) daily. Information on pregnancy outcomes are derived from women-and-physician information.
We foresee to analyze the data considering all the adverse outcomes of pregnancy taken together in a global end point (e.g.: CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age). A total of about 1,000 pregnancies need to be evaluated to detect an absolute reduction of the frequency of 8%. Since the sample size needed for studying outcomes separately is large, this project also promotes an international prospective meta-analysis.

Discussion

The rationale of these randomized clinical trials (RCTs) is the hypothesis that a higher intake of FA is related to a higher risk reduction of NTDs, other CMs and other adverse pregnancy outcomes. Our hope is that these trials will act as catalysers, and lead to other large RCTs studying the effects of this supplementation on CMs and other infant and maternal outcomes.

Trial registration

Italian trial: ClinicalTrials.gov Identifier: NCT01244347.
Dutch trial: Dutch Trial Register ID: NTR3161.
Literature
2.
go back to reference Yi Y, Lindemann M, Colligs A, Snowball C: Economic burden of neural tube defects and impact of prevention with folic acid: a literature review. Eur J Pediatr. 2011, 170: 1391-1400. 10.1007/s00431-011-1492-8.PubMedPubMedCentral Yi Y, Lindemann M, Colligs A, Snowball C: Economic burden of neural tube defects and impact of prevention with folic acid: a literature review. Eur J Pediatr. 2011, 170: 1391-1400. 10.1007/s00431-011-1492-8.PubMedPubMedCentral
3.
go back to reference Sutton M, Daly LE, Kirke PN: Survival and disability in a cohort of neural tube defect births in Dublin, Ireland. Birth Defects Research (Part A). 2008, 82: 701-709. 10.1002/bdra.20498. Sutton M, Daly LE, Kirke PN: Survival and disability in a cohort of neural tube defect births in Dublin, Ireland. Birth Defects Research (Part A). 2008, 82: 701-709. 10.1002/bdra.20498.
4.
go back to reference Blencowe H, Cousens S, Oestergaard MZ, Chou D, Moller AB, Narwal R, Adler A, Garcia CV, Rohde S, Say L, Lawn JE: National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet. 2012, 379: 2162-2172. 10.1016/S0140-6736(12)60820-4.PubMed Blencowe H, Cousens S, Oestergaard MZ, Chou D, Moller AB, Narwal R, Adler A, Garcia CV, Rohde S, Say L, Lawn JE: National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet. 2012, 379: 2162-2172. 10.1016/S0140-6736(12)60820-4.PubMed
5.
go back to reference Saigal S, Doyle LW: Preterm Birth 3. An overview of mortality and sequelae of preterm birth from infancy to adulthood. Lancet. 2008, 371: 261-269. 10.1016/S0140-6736(08)60136-1.PubMed Saigal S, Doyle LW: Preterm Birth 3. An overview of mortality and sequelae of preterm birth from infancy to adulthood. Lancet. 2008, 371: 261-269. 10.1016/S0140-6736(08)60136-1.PubMed
6.
go back to reference Gluckman PD, Hanson MA, Cooper C, Thornburg KL: Effect of in utero and early-life conditions on adult health and disease. N Engl J Med. 2008, 359: 61-73. 10.1056/NEJMra0708473.PubMedPubMedCentral Gluckman PD, Hanson MA, Cooper C, Thornburg KL: Effect of in utero and early-life conditions on adult health and disease. N Engl J Med. 2008, 359: 61-73. 10.1056/NEJMra0708473.PubMedPubMedCentral
7.
go back to reference Chang HH, Larson J, Blencowe H, Spong CY, Howson CP, Caims-Smith S, Lackritz EM, Lee SK, Mason E, Serazin AC, Walani S, Simpson JL, Lawn JE, on behalf of the Born Too Soon preterm prevention analysis group: Preventing preterm births: analysis of trends and potential reductions with interventions in 39 countries with very high human development index. Lancet. 2013, 381: 223-234. 10.1016/S0140-6736(12)61856-X.PubMed Chang HH, Larson J, Blencowe H, Spong CY, Howson CP, Caims-Smith S, Lackritz EM, Lee SK, Mason E, Serazin AC, Walani S, Simpson JL, Lawn JE, on behalf of the Born Too Soon preterm prevention analysis group: Preventing preterm births: analysis of trends and potential reductions with interventions in 39 countries with very high human development index. Lancet. 2013, 381: 223-234. 10.1016/S0140-6736(12)61856-X.PubMed
8.
go back to reference Mangham LJ, Petrou S, Doyle LW, Draper ES, Marlow N: The cost of preterm birth throughout childhood in England and Wales. Pediatrics. 2009, 123: 312-327. 10.1542/peds.2008-1827. Mangham LJ, Petrou S, Doyle LW, Draper ES, Marlow N: The cost of preterm birth throughout childhood in England and Wales. Pediatrics. 2009, 123: 312-327. 10.1542/peds.2008-1827.
9.
go back to reference McIntire DD, Bloom SL, Casey BM, Leveno KJ: Birth weight in relation to morbidity and mortality among newborn infants. N Engl J Med. 1999, 340: 1234-1238. 10.1056/NEJM199904223401603.PubMed McIntire DD, Bloom SL, Casey BM, Leveno KJ: Birth weight in relation to morbidity and mortality among newborn infants. N Engl J Med. 1999, 340: 1234-1238. 10.1056/NEJM199904223401603.PubMed
10.
go back to reference Richards M, Hardy R, Kuh D, Wadsworth MEJ: Birth weight and cognitive function in the British 1946 birth cohort: longitudinal population based study. BMJ. 2001, 322: 199-203. 10.1136/bmj.322.7280.199.PubMedPubMedCentral Richards M, Hardy R, Kuh D, Wadsworth MEJ: Birth weight and cognitive function in the British 1946 birth cohort: longitudinal population based study. BMJ. 2001, 322: 199-203. 10.1136/bmj.322.7280.199.PubMedPubMedCentral
11.
go back to reference Streimish IG, Ehrenkranz RA, Allred EN, O’Shea TM, Kuban KC, Paneth N, Leviton A, the ELGAN Study Investigators: Birth weight and fetal weight-growth restriction: Impact on neurodevelopment. Early Hum Dev. 2012, 88: 765-771. 10.1016/j.earlhumdev.2012.04.004.PubMedPubMedCentral Streimish IG, Ehrenkranz RA, Allred EN, O’Shea TM, Kuban KC, Paneth N, Leviton A, the ELGAN Study Investigators: Birth weight and fetal weight-growth restriction: Impact on neurodevelopment. Early Hum Dev. 2012, 88: 765-771. 10.1016/j.earlhumdev.2012.04.004.PubMedPubMedCentral
12.
go back to reference Sibai B, Dekker G, Kupferminc M: Pre-eclampsia. Lancet. 2005, 365: 785-799. 10.1016/S0140-6736(05)17987-2.PubMed Sibai B, Dekker G, Kupferminc M: Pre-eclampsia. Lancet. 2005, 365: 785-799. 10.1016/S0140-6736(05)17987-2.PubMed
13.
go back to reference Steegers E, von Dadelszen P, Duvekot J, Pijnenborg R: Pre-eclampsia. Lancet. 2010, 376: 631-644. 10.1016/S0140-6736(10)60279-6.PubMed Steegers E, von Dadelszen P, Duvekot J, Pijnenborg R: Pre-eclampsia. Lancet. 2010, 376: 631-644. 10.1016/S0140-6736(10)60279-6.PubMed
14.
go back to reference Irgens HU, Reisaeter L, Irgens LM, Lie RT: Long term mortality of mothers and fathers after pre-eclampsia: population based cohort study. BMJ. 2001, 323: 1213-1216. 10.1136/bmj.323.7323.1213.PubMedPubMedCentral Irgens HU, Reisaeter L, Irgens LM, Lie RT: Long term mortality of mothers and fathers after pre-eclampsia: population based cohort study. BMJ. 2001, 323: 1213-1216. 10.1136/bmj.323.7323.1213.PubMedPubMedCentral
15.
go back to reference Wilson BJ, Watson MS, Prescott GJ, Sunderland S, Campbell DM, Hannaford P, Smith WC: Hypertensive diseases of pregnancy and risk of hypertension and stroke in later life: results from cohort study. BMJ. 2003, 326: 845-849. 10.1136/bmj.326.7394.845.PubMedPubMedCentral Wilson BJ, Watson MS, Prescott GJ, Sunderland S, Campbell DM, Hannaford P, Smith WC: Hypertensive diseases of pregnancy and risk of hypertension and stroke in later life: results from cohort study. BMJ. 2003, 326: 845-849. 10.1136/bmj.326.7394.845.PubMedPubMedCentral
16.
go back to reference Haukkamaa L, Salminen M, Laivuori H, Leinonen H, Hiilesmaa V, Kaaja R: Risk for subsequent coronary artery disease after preeclampsia. Am J Cardiol. 2004, 93: 805-808. 10.1016/j.amjcard.2003.11.065.PubMed Haukkamaa L, Salminen M, Laivuori H, Leinonen H, Hiilesmaa V, Kaaja R: Risk for subsequent coronary artery disease after preeclampsia. Am J Cardiol. 2004, 93: 805-808. 10.1016/j.amjcard.2003.11.065.PubMed
17.
go back to reference Bellamy L, Casas JP, Hingorani AD, Williams DJ: Pre-eclampsia and risk of cardiovascular disease and cancer in later life: systematic review and meta-analysis. BMJ. 2007, 335: 974-977. 10.1136/bmj.39335.385301.BE.PubMedPubMedCentral Bellamy L, Casas JP, Hingorani AD, Williams DJ: Pre-eclampsia and risk of cardiovascular disease and cancer in later life: systematic review and meta-analysis. BMJ. 2007, 335: 974-977. 10.1136/bmj.39335.385301.BE.PubMedPubMedCentral
18.
go back to reference March of Dimes, The Partnership of Maternal, Newborn and Child Health, Save the Children, World Health Organization: Born too soon: the global action report on preterm birth. 2012, Geneva: World Health Organization March of Dimes, The Partnership of Maternal, Newborn and Child Health, Save the Children, World Health Organization: Born too soon: the global action report on preterm birth. 2012, Geneva: World Health Organization
19.
go back to reference Bhutta ZA, Das JK, Rizvi A, Gaffey MF, Walker N, Horton S, Webb P, Lartey A, Black RE: Lancet Interventions Review Group, Maternal and Child Nutrition Study Group: Evidence based interventions for improvement of maternal and child nutrition: what can be done and at what cost?. Lancet. 2013, 382: 452-477. 10.1016/S0140-6736(13)60996-4.PubMed Bhutta ZA, Das JK, Rizvi A, Gaffey MF, Walker N, Horton S, Webb P, Lartey A, Black RE: Lancet Interventions Review Group, Maternal and Child Nutrition Study Group: Evidence based interventions for improvement of maternal and child nutrition: what can be done and at what cost?. Lancet. 2013, 382: 452-477. 10.1016/S0140-6736(13)60996-4.PubMed
20.
go back to reference Tamura T, Picciano MF: Folate and human reproduction. Am J Clin Nutr. 2006, 83: 993-1016.PubMed Tamura T, Picciano MF: Folate and human reproduction. Am J Clin Nutr. 2006, 83: 993-1016.PubMed
21.
go back to reference Bailey LB, Gregory JF: Folate metabolism and requirements. J Nutr. 1999, 129: 779-782.PubMed Bailey LB, Gregory JF: Folate metabolism and requirements. J Nutr. 1999, 129: 779-782.PubMed
22.
go back to reference Chanarin I: The folates. Vitamins in medicine. Volume 1. Edited by: Barker BM, Bender DA. 1980, London: William Heinemann Medical Books, 247-314. 4 Chanarin I: The folates. Vitamins in medicine. Volume 1. Edited by: Barker BM, Bender DA. 1980, London: William Heinemann Medical Books, 247-314. 4
23.
go back to reference Steinberg SE: Mechanisms of folate homeostasis. Am J Physiol. 1984, 246: 319-324. Steinberg SE: Mechanisms of folate homeostasis. Am J Physiol. 1984, 246: 319-324.
24.
go back to reference Scholl TO, Johnson WG: Folic acid: influence on the outcome of pregnancy. Am J Clin Nutr. 2000, 71: 1295S-1303S.PubMed Scholl TO, Johnson WG: Folic acid: influence on the outcome of pregnancy. Am J Clin Nutr. 2000, 71: 1295S-1303S.PubMed
25.
go back to reference Ray JG, Laskin CA: Folic acid and homocysteine metabolic defects and the risk of placental abruption, pre-eclampsia and spontaneous pregnancy loss: a systematic review. Placenta. 1999, 20: 519-529. 10.1053/plac.1999.0417.PubMed Ray JG, Laskin CA: Folic acid and homocysteine metabolic defects and the risk of placental abruption, pre-eclampsia and spontaneous pregnancy loss: a systematic review. Placenta. 1999, 20: 519-529. 10.1053/plac.1999.0417.PubMed
26.
go back to reference Fowler B: The folate cycle and disease in humans. Kidney Int Suppl. 2001, 78: S221-S229.PubMed Fowler B: The folate cycle and disease in humans. Kidney Int Suppl. 2001, 78: S221-S229.PubMed
27.
go back to reference Vollset SE, Refsum H, Irgens LM, Emblem BM, Tverdal A, Gjessing HK: Plasma total homocysteine, pregnancy complications, and adverse pregnancy outcomes: the Hordaland Homocysteine Study. Am J Clin Nutr. 2000, 71: 962-968.PubMed Vollset SE, Refsum H, Irgens LM, Emblem BM, Tverdal A, Gjessing HK: Plasma total homocysteine, pregnancy complications, and adverse pregnancy outcomes: the Hordaland Homocysteine Study. Am J Clin Nutr. 2000, 71: 962-968.PubMed
28.
go back to reference Bergen NE, Jaddoe VW, Timmermans S, Hofman A, Lindemans J, Russcher H, Raat H, Steegers-Theunissen RP, Steegers EA: Homocysteine and folate concentrations in early pregnancy and the risk of adverse pregnancy outcomes: the Generation R Study. BJOG. 2012, 119: 739-751. 10.1111/j.1471-0528.2012.03321.x.PubMed Bergen NE, Jaddoe VW, Timmermans S, Hofman A, Lindemans J, Russcher H, Raat H, Steegers-Theunissen RP, Steegers EA: Homocysteine and folate concentrations in early pregnancy and the risk of adverse pregnancy outcomes: the Generation R Study. BJOG. 2012, 119: 739-751. 10.1111/j.1471-0528.2012.03321.x.PubMed
29.
go back to reference MRC Vitamin Study Research Group: Prevention of neural tube defects: results of the MRC Vitamin Study. Lancet. 1991, 338: 131-137. MRC Vitamin Study Research Group: Prevention of neural tube defects: results of the MRC Vitamin Study. Lancet. 1991, 338: 131-137.
30.
go back to reference Czeizel AE, Dudas I: Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med. 1992, 327: 1832-1835. 10.1056/NEJM199212243272602.PubMed Czeizel AE, Dudas I: Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med. 1992, 327: 1832-1835. 10.1056/NEJM199212243272602.PubMed
31.
go back to reference Smithells RW, Sheppard S, Wild J, Schorah CJ: Prevention of neural tube defect recurrences in Yorkshire: final report. Lancet. 1989, 2: 498-499.PubMed Smithells RW, Sheppard S, Wild J, Schorah CJ: Prevention of neural tube defect recurrences in Yorkshire: final report. Lancet. 1989, 2: 498-499.PubMed
32.
go back to reference Berry RJ, Li Z, Erickson JD, Li S, Moore CA, Wang H, Mulinare J, Zhao P, Wong LY, Gindler J, Hong SX, Correa A: Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention. N Engl J Med. 1999, 341: 1485-1490. 10.1056/NEJM199911113412001.PubMed Berry RJ, Li Z, Erickson JD, Li S, Moore CA, Wang H, Mulinare J, Zhao P, Wong LY, Gindler J, Hong SX, Correa A: Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention. N Engl J Med. 1999, 341: 1485-1490. 10.1056/NEJM199911113412001.PubMed
33.
go back to reference De-Regil LM, Fernandez-Gaxiola AC, Dowswell T, Pena-Rosas JP: Effects and safety of periconceptional folate supplementation for preventing birth defects. Cochrane Database Syst Rev. 2010, Issue 10. Art.No.: CD007950. DOI:10.1002/14651858.CD007950.pub2 De-Regil LM, Fernandez-Gaxiola AC, Dowswell T, Pena-Rosas JP: Effects and safety of periconceptional folate supplementation for preventing birth defects. Cochrane Database Syst Rev. 2010, Issue 10. Art.No.: CD007950. DOI:10.1002/14651858.CD007950.pub2
34.
go back to reference 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 III. Congenital anomalies. An observational study. Eur J Obstet Gynecol Reprod Biol. 1999, 87: 115-118. 10.1016/S0301-2115(99)00086-X.PubMed 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 III. Congenital anomalies. An observational study. Eur J Obstet Gynecol Reprod Biol. 1999, 87: 115-118. 10.1016/S0301-2115(99)00086-X.PubMed
35.
go back to reference Czeizel AE, Dobo M, Vargha P: Hungarian cohort-controlled trial of periconceptional multivitamin supplementation shows a reduction in certain congenital abnormalities. Birth Defects Res A Clin Mol Teratol. 2004, 70: 853-861. 10.1002/bdra.20086.PubMed Czeizel AE, Dobo M, Vargha P: Hungarian cohort-controlled trial of periconceptional multivitamin supplementation shows a reduction in certain congenital abnormalities. Birth Defects Res A Clin Mol Teratol. 2004, 70: 853-861. 10.1002/bdra.20086.PubMed
36.
go back to reference Botto LD, Olney RS, Erickson JD: Vitamin supplements and the risk for congenital anomalies other than neural tube defects. Am J Med Genet. 2004, 125: 12-21. Botto LD, Olney RS, Erickson JD: Vitamin supplements and the risk for congenital anomalies other than neural tube defects. Am J Med Genet. 2004, 125: 12-21.
37.
go back to reference Yang W, Zeng L, Cheng Y, Chen Z, Wang X, Li X, Yan H: The effects of periconceptional risk factor exposure and micronutrient supplementation on birth defects in Shaanxi Province in Western China. PLoS One. 2012, 7: e53429-10.1371/journal.pone.0053429.PubMedPubMedCentral Yang W, Zeng L, Cheng Y, Chen Z, Wang X, Li X, Yan H: The effects of periconceptional risk factor exposure and micronutrient supplementation on birth defects in Shaanxi Province in Western China. PLoS One. 2012, 7: e53429-10.1371/journal.pone.0053429.PubMedPubMedCentral
38.
go back to reference Goh YI, Bollano E, Einarson TR, Koren G: Prenatal multivitamin supplementation and rates of congenital anomalies: a meta-analysis. J Obstet Gynaecol Can. 2006, 28: 680-689.PubMed Goh YI, Bollano E, Einarson TR, Koren G: Prenatal multivitamin supplementation and rates of congenital anomalies: a meta-analysis. J Obstet Gynaecol Can. 2006, 28: 680-689.PubMed
39.
go back to reference Badovinac RL, Werler MM, Williams PL, Kelsey KT, Hayes C: Folic acid-containing supplement consumption during pregnancy and risk for oral clefts: a meta-analysis. Birth Defects Res A Clin Mol Teratol. 2007, 79: 8-15. 10.1002/bdra.20315.PubMed Badovinac RL, Werler MM, Williams PL, Kelsey KT, Hayes C: Folic acid-containing supplement consumption during pregnancy and risk for oral clefts: a meta-analysis. Birth Defects Res A Clin Mol Teratol. 2007, 79: 8-15. 10.1002/bdra.20315.PubMed
40.
go back to reference Johnson CY, Little J: Folate intake, markers of folate status and oral clefts: is the evidence converging?. Int J Epidemiol. 2008, 37: 1041-1058. 10.1093/ije/dyn098.PubMed Johnson CY, Little J: Folate intake, markers of folate status and oral clefts: is the evidence converging?. Int J Epidemiol. 2008, 37: 1041-1058. 10.1093/ije/dyn098.PubMed
41.
go back to reference Li S, Chao A, Li Z, Moore CA, Liu Y, Zhu J, Erickson JD, Hao L, Berry RJ: Folic acid use and nonsyndromic orofacial clefts in China. A Prospective Cohort Study Epidemiology. 2012, 23: 423-432.PubMed Li S, Chao A, Li Z, Moore CA, Liu Y, Zhu J, Erickson JD, Hao L, Berry RJ: Folic acid use and nonsyndromic orofacial clefts in China. A Prospective Cohort Study Epidemiology. 2012, 23: 423-432.PubMed
42.
go back to reference Butali A, Little J, Chevrier C, Cordier S, Steegers-Theunissen R, Jugessur A, Oladugba B, Mossey PA: Folic acid supplementation use and the MTHFR C677T polymorphism in orofacial clefts etiology: an individual participant data pooled-analysis. Birth Defects Res A Clin Mol Teratol. 2013, 97: 509-514. 10.1002/bdra.23133.PubMed Butali A, Little J, Chevrier C, Cordier S, Steegers-Theunissen R, Jugessur A, Oladugba B, Mossey PA: Folic acid supplementation use and the MTHFR C677T polymorphism in orofacial clefts etiology: an individual participant data pooled-analysis. Birth Defects Res A Clin Mol Teratol. 2013, 97: 509-514. 10.1002/bdra.23133.PubMed
43.
go back to reference 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 offspring. Am J Med Genet. 1995, 59: 536-545. 10.1002/ajmg.1320590428.PubMed 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 offspring. Am J Med Genet. 1995, 59: 536-545. 10.1002/ajmg.1320590428.PubMed
44.
go back to reference Botto LD, Mulinare J, Erickson JD: Occurrence of congenital heart defects in relation to maternal multivitamin use. Am J Epidemiol. 2000, 151: 878-884. 10.1093/oxfordjournals.aje.a010291.PubMed Botto LD, Mulinare J, Erickson JD: Occurrence of congenital heart defects in relation to maternal multivitamin use. Am J Epidemiol. 2000, 151: 878-884. 10.1093/oxfordjournals.aje.a010291.PubMed
45.
go back to reference Ionescu-Ittu R, Marelli AJ, Mackie AS, Pilote L: Prevalence of severe congenital heart disease after folic acid fortification of grain products: time trend analysis in Quebec, Canada. BMJ. 2009, 338: b1673-10.1136/bmj.b1673.PubMedPubMedCentral Ionescu-Ittu R, Marelli AJ, Mackie AS, Pilote L: Prevalence of severe congenital heart disease after folic acid fortification of grain products: time trend analysis in Quebec, Canada. BMJ. 2009, 338: b1673-10.1136/bmj.b1673.PubMedPubMedCentral
46.
go back to reference van Beynum IM, Kapusta L, Bakker MK, den Heijer M, Blom HJ, de Walle HE: Protective effect of periconceptional folic acid supplements on the risk of congenital heart defects: a registry-based case–control study in the northern Netherlands. Eur Heart J. 2010, 31: 464-471. 10.1093/eurheartj/ehp479.PubMed van Beynum IM, Kapusta L, Bakker MK, den Heijer M, Blom HJ, de Walle HE: Protective effect of periconceptional folic acid supplements on the risk of congenital heart defects: a registry-based case–control study in the northern Netherlands. Eur Heart J. 2010, 31: 464-471. 10.1093/eurheartj/ehp479.PubMed
47.
go back to reference Li DK, Daling JR, Mueller BA, Hickok DE, Fantel AG, Weiss NS: Periconceptional multivitamin use in relation to the risk of congenital urinary tract anomalies. Epidemiology. 1995, 6: 212-218. 10.1097/00001648-199505000-00004.PubMed Li DK, Daling JR, Mueller BA, Hickok DE, Fantel AG, Weiss NS: Periconceptional multivitamin use in relation to the risk of congenital urinary tract anomalies. Epidemiology. 1995, 6: 212-218. 10.1097/00001648-199505000-00004.PubMed
48.
go back to reference Yang Q, Khoury MJ, Olney RS: Does periconceptional multivitamin use reduce the risk for limb deficiency in offspring?. Epidemiology. 1997, 8: 157-161. 10.1097/00001648-199703000-00006.PubMed Yang Q, Khoury MJ, Olney RS: Does periconceptional multivitamin use reduce the risk for limb deficiency in offspring?. Epidemiology. 1997, 8: 157-161. 10.1097/00001648-199703000-00006.PubMed
49.
go back to reference Botto LD, Mulinare J, Erickson JD: Occurrence of omphalocele in relation to maternal multivitamin use: a population-based study. Pediatrics. 2002, 109: 904-908. 10.1542/peds.109.5.904.PubMed Botto LD, Mulinare J, Erickson JD: Occurrence of omphalocele in relation to maternal multivitamin use: a population-based study. Pediatrics. 2002, 109: 904-908. 10.1542/peds.109.5.904.PubMed
50.
go back to reference Myers MF, Li S, Correa-Villasenor A, Li Z, Moore CA, Hong SX, Berry RJ, the China-US Collaborative Project for Neural Tube Defect Prevention: Folic Acid Supplementation and Risk for Imperforate Anus in China. Am J Epidemiol. 2001, 154: 1051-1056. 10.1093/aje/154.11.1051.PubMed Myers MF, Li S, Correa-Villasenor A, Li Z, Moore CA, Hong SX, Berry RJ, the China-US Collaborative Project for Neural Tube Defect Prevention: Folic Acid Supplementation and Risk for Imperforate Anus in China. Am J Epidemiol. 2001, 154: 1051-1056. 10.1093/aje/154.11.1051.PubMed
51.
go back to reference Czeizel AE, Puho E: Maternal use of nutritional supplements during the first month of pregnancy and decreased risk of Down’s syndrome: case–control study. Nutrition. 2005, 21: 698-704. 10.1016/j.nut.2004.10.017.PubMed Czeizel AE, Puho E: Maternal use of nutritional supplements during the first month of pregnancy and decreased risk of Down’s syndrome: case–control study. Nutrition. 2005, 21: 698-704. 10.1016/j.nut.2004.10.017.PubMed
52.
go back to reference Ray JG, Meier C, Vermeulen MJ, Cole DE, Wyatt PR: Prevalence of trisomy 21 following folic acid food fortification. Am J Med Genet. 2003, 120A: 309-313. 10.1002/ajmg.a.20161.PubMed Ray JG, Meier C, Vermeulen MJ, Cole DE, Wyatt PR: Prevalence of trisomy 21 following folic acid food fortification. Am J Med Genet. 2003, 120A: 309-313. 10.1002/ajmg.a.20161.PubMed
53.
go back to reference Hollis ND, Allen EG, Oliver TR, Tinker SW, Druschel C, Hobbs CA, O’Leary LA, Romitti PA, Royle MH, Torfs CP, Freeman SB, Sherman SL, Bean LJ: preconception folic acid supplementation and risk for chromosome 21 nondisjunction: a report from the National Down Syndrome Project. Am J Med Genet. 2013, 161A: 438-444.PubMed Hollis ND, Allen EG, Oliver TR, Tinker SW, Druschel C, Hobbs CA, O’Leary LA, Romitti PA, Royle MH, Torfs CP, Freeman SB, Sherman SL, Bean LJ: preconception folic acid supplementation and risk for chromosome 21 nondisjunction: a report from the National Down Syndrome Project. Am J Med Genet. 2013, 161A: 438-444.PubMed
54.
go back to reference Charles DH, Ness AR, Campbell D, Smith GD, Whitley E, Hall MH: Folic acid supplements in pregnancy and birth outcome: re-analysis of a large randomised controlled trial and update of Cochrane review. Paediatr Perinat Epidemiol. 2005, 19: 112-124. 10.1111/j.1365-3016.2005.00633.x.PubMed Charles DH, Ness AR, Campbell D, Smith GD, Whitley E, Hall MH: Folic acid supplements in pregnancy and birth outcome: re-analysis of a large randomised controlled trial and update of Cochrane review. Paediatr Perinat Epidemiol. 2005, 19: 112-124. 10.1111/j.1365-3016.2005.00633.x.PubMed
55.
go back to reference Chiaffarino F, Ascone GB, Bortolus R, Mastroiacovo P, Ricci E, Cipriani S, Parazzini F: Effects of folic acid supplementation on pregnancy outcomes: a review of randomized clinical trials. Minerva Ginecol. 2010, 62: 293-301.PubMed Chiaffarino F, Ascone GB, Bortolus R, Mastroiacovo P, Ricci E, Cipriani S, Parazzini F: Effects of folic acid supplementation on pregnancy outcomes: a review of randomized clinical trials. Minerva Ginecol. 2010, 62: 293-301.PubMed
56.
go back to reference Kim MW, Hong SC, Choi JS, Han JY, Oh MJ, Kim HJ, Nava-Ocampo A, Koren G: Homocysteine, folate and pregnancy outcomes. J Obstet Gynaecol. 2012, 32: 520-524. 10.3109/01443615.2012.693984.PubMed Kim MW, Hong SC, Choi JS, Han JY, Oh MJ, Kim HJ, Nava-Ocampo A, Koren G: Homocysteine, folate and pregnancy outcomes. J Obstet Gynaecol. 2012, 32: 520-524. 10.3109/01443615.2012.693984.PubMed
57.
go back to reference Furness D, Fenech M, Dekker G, Khong TY, Roberts C, Hague W: Folate, Vitamin B12, Vitamin B6 and homocysteine: impact on pregnancy outcome. Matern Child Nutr. 2013, 9: 155-166. 10.1111/j.1740-8709.2011.00364.x.PubMed Furness D, Fenech M, Dekker G, Khong TY, Roberts C, Hague W: Folate, Vitamin B12, Vitamin B6 and homocysteine: impact on pregnancy outcome. Matern Child Nutr. 2013, 9: 155-166. 10.1111/j.1740-8709.2011.00364.x.PubMed
58.
go back to reference Yamada T, Morikawa M, Yamada T, Kishi R, Sengoku K, Endo T, Saito T, Cho K, Minakami H: First-trimester serum folate levels and subsequent risk of abortion and preterm birth among Japanese women with singleton pregnancies. Arch Gynecol Obstet. 2013, 287: 9-14. 10.1007/s00404-012-2501-5.PubMed Yamada T, Morikawa M, Yamada T, Kishi R, Sengoku K, Endo T, Saito T, Cho K, Minakami H: First-trimester serum folate levels and subsequent risk of abortion and preterm birth among Japanese women with singleton pregnancies. Arch Gynecol Obstet. 2013, 287: 9-14. 10.1007/s00404-012-2501-5.PubMed
59.
go back to reference Nelen WL, Blom HJ, Steegers EA, Den Heijer M, Thomas CM, Eskes TK: Homocysteine and folate levels as risk factors for recurrent early pregnancy loss. Obstet Gynecol. 2000, 95: 519-524. 10.1016/S0029-7844(99)00610-9.PubMed Nelen WL, Blom HJ, Steegers EA, Den Heijer M, Thomas CM, Eskes TK: Homocysteine and folate levels as risk factors for recurrent early pregnancy loss. Obstet Gynecol. 2000, 95: 519-524. 10.1016/S0029-7844(99)00610-9.PubMed
60.
go back to reference Gindler J, Li Z, Berry RJ, Zheng J, Correa A, Sun X, Wong L, Cheng L, Erickson JD, Wang Y, Tong Q, for the Jiaxing City Collaborative Project on Neural Tube Defect Prevention: Folic acid supplements during pregnancy and risk of miscarriage. Lancet. 2001, 358: 796-800. 10.1016/S0140-6736(01)05969-4.PubMed Gindler J, Li Z, Berry RJ, Zheng J, Correa A, Sun X, Wong L, Cheng L, Erickson JD, Wang Y, Tong Q, for the Jiaxing City Collaborative Project on Neural Tube Defect Prevention: Folic acid supplements during pregnancy and risk of miscarriage. Lancet. 2001, 358: 796-800. 10.1016/S0140-6736(01)05969-4.PubMed
61.
go back to reference George L, Mills JL, Johansson AL, Nordmark A, Olander B, Granath F, Cnattingius S: Plasma folate levels and risk of spontaneous abortion. JAMA. 2002, 288: 1867-1873. 10.1001/jama.288.15.1867.PubMed George L, Mills JL, Johansson AL, Nordmark A, Olander B, Granath F, Cnattingius S: Plasma folate levels and risk of spontaneous abortion. JAMA. 2002, 288: 1867-1873. 10.1001/jama.288.15.1867.PubMed
62.
go back to reference Ronnenberg AG, Goldman MB, Chen D, Aitken IW, Willett WC, Selhub J, Xu X: Preconception Folate and Vitamin B6 Status and clinical spontaneous abortion in Chinese women. Obstet Gynecol. 2002, 100: 107-113. 10.1016/S0029-7844(02)01978-6.PubMed Ronnenberg AG, Goldman MB, Chen D, Aitken IW, Willett WC, Selhub J, Xu X: Preconception Folate and Vitamin B6 Status and clinical spontaneous abortion in Chinese women. Obstet Gynecol. 2002, 100: 107-113. 10.1016/S0029-7844(02)01978-6.PubMed
63.
go back to reference Ronnenberg AG, Venners SA, Xu X, Chen C, Wang L, Guang W, Huang A, Wang X: Preconception B-Vitamin and homocysteine status, conception, and early pregnancy loss. Am J Epidemiol. 2007, 166: 304-312. 10.1093/aje/kwm078.PubMed Ronnenberg AG, Venners SA, Xu X, Chen C, Wang L, Guang W, Huang A, Wang X: Preconception B-Vitamin and homocysteine status, conception, and early pregnancy loss. Am J Epidemiol. 2007, 166: 304-312. 10.1093/aje/kwm078.PubMed
64.
go back to reference Byrne J: Periconceptional folic acid prevents miscarriage in Irish families with neural tube defects. Ir J Med Sci. 2011, 180: 59-62. 10.1007/s11845-010-0629-5.PubMed Byrne J: Periconceptional folic acid prevents miscarriage in Irish families with neural tube defects. Ir J Med Sci. 2011, 180: 59-62. 10.1007/s11845-010-0629-5.PubMed
65.
go back to reference Zhang X, Li J, Gu Y, Zhao Y, Wang Z, Jia G: A pilot study on environmental and behavioral factors related to missed abortion. Environ Health Prev Med. 2011, 16: 273-278. 10.1007/s12199-010-0196-4.PubMedPubMedCentral Zhang X, Li J, Gu Y, Zhao Y, Wang Z, Jia G: A pilot study on environmental and behavioral factors related to missed abortion. Environ Health Prev Med. 2011, 16: 273-278. 10.1007/s12199-010-0196-4.PubMedPubMedCentral
66.
go back to reference Catov JM, Bodnar LM, Ness RB, Markovic N, Roberts JM: Association of periconceptional multivitamin use and risk of preterm or small-for-gestational-age births. Am J Epidemiol. 2007, 166: 296-303. 10.1093/aje/kwm071.PubMed Catov JM, Bodnar LM, Ness RB, Markovic N, Roberts JM: Association of periconceptional multivitamin use and risk of preterm or small-for-gestational-age births. Am J Epidemiol. 2007, 166: 296-303. 10.1093/aje/kwm071.PubMed
67.
go back to reference Timmermans S, Jaddoe VW, Hofman A, Steegers-Theunissen RP, Steegers EA: Periconception folic acid supplementation, fetal growth and the risks of low birth weight and preterm birth: the Generation R Study. Br J Nutr. 2009, 102: 777-785. 10.1017/S0007114509288994.PubMed Timmermans S, Jaddoe VW, Hofman A, Steegers-Theunissen RP, Steegers EA: Periconception folic acid supplementation, fetal growth and the risks of low birth weight and preterm birth: the Generation R Study. Br J Nutr. 2009, 102: 777-785. 10.1017/S0007114509288994.PubMed
68.
go back to reference Alwan NA, Greenwood DC, Simpson NA, McArdle HJ, Cade JE: The relationship between dietary supplement use in late pregnancy and birth outcomes: a cohort study in British women. Br J Obstet Gynecol. 2010, 117: 821-829. 10.1111/j.1471-0528.2010.02549.x. Alwan NA, Greenwood DC, Simpson NA, McArdle HJ, Cade JE: The relationship between dietary supplement use in late pregnancy and birth outcomes: a cohort study in British women. Br J Obstet Gynecol. 2010, 117: 821-829. 10.1111/j.1471-0528.2010.02549.x.
69.
go back to reference Czeizel AE, Puho’ EH, Langmar Z, Acs N, Banhidy F: Possible association of folic acid supplementation during pregnancy with reduction of preterm birth: a population-based study. Eur J Obstet Gynecol Reprod Biol. 2010, 148: 135-140. 10.1016/j.ejogrb.2009.10.016.PubMed Czeizel AE, Puho’ EH, Langmar Z, Acs N, Banhidy F: Possible association of folic acid supplementation during pregnancy with reduction of preterm birth: a population-based study. Eur J Obstet Gynecol Reprod Biol. 2010, 148: 135-140. 10.1016/j.ejogrb.2009.10.016.PubMed
70.
go back to reference Bukowski R, Malone FD, Porter FT, Nyberg DA, Comstock CH, Hankins GD, Eddleman K, Gross SJ, Dugoff L, Craigo SD, Timor-Tritsch IE, Carr SR, Wolfe HM, D’Alton ME: Preconceptional folate supplementation and the risk of spontaneous preterm birth: a cohort study. PLoS Med. 2009, 6: e1000061-10.1371/journal.pmed.1000061.PubMedPubMedCentral Bukowski R, Malone FD, Porter FT, Nyberg DA, Comstock CH, Hankins GD, Eddleman K, Gross SJ, Dugoff L, Craigo SD, Timor-Tritsch IE, Carr SR, Wolfe HM, D’Alton ME: Preconceptional folate supplementation and the risk of spontaneous preterm birth: a cohort study. PLoS Med. 2009, 6: e1000061-10.1371/journal.pmed.1000061.PubMedPubMedCentral
71.
go back to reference Bodnar LM, Himes KP, Venkataramanan R, Chen J, Evans RW, Meyer JL, Simhan HN: Maternal serum folate species in early pregnancy and risk of preterm birth. Am J Clin Nutr. 2010, 92: 864-871. 10.3945/ajcn.2010.29675.PubMedPubMedCentral Bodnar LM, Himes KP, Venkataramanan R, Chen J, Evans RW, Meyer JL, Simhan HN: Maternal serum folate species in early pregnancy and risk of preterm birth. Am J Clin Nutr. 2010, 92: 864-871. 10.3945/ajcn.2010.29675.PubMedPubMedCentral
72.
go back to reference Catov JM, Bodnar LM, Olsen J, Olsen S, Nohr EA: Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort. Am J Clin Nutr. 2011, 94: 906-912. 10.3945/ajcn.111.012393.PubMedPubMedCentral Catov JM, Bodnar LM, Olsen J, Olsen S, Nohr EA: Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort. Am J Clin Nutr. 2011, 94: 906-912. 10.3945/ajcn.111.012393.PubMedPubMedCentral
73.
go back to reference Shaw GM, Carmichael SL, Yang W, Siega-Riz AM: National Birth Defects Prevention Study. Periconceptional intake of folic acid and food folate and risks of preterm delivery. Am J Perinatol. 2011, 28: 747-752. 10.1055/s-0031-1280855.PubMed Shaw GM, Carmichael SL, Yang W, Siega-Riz AM: National Birth Defects Prevention Study. Periconceptional intake of folic acid and food folate and risks of preterm delivery. Am J Perinatol. 2011, 28: 747-752. 10.1055/s-0031-1280855.PubMed
74.
go back to reference Dhobale M, Chavan P, Kulkarni A, Mehendale S, Pisal H, Joshi S: Reduced Folate, Increased Vitamin B12 and Homocysteine Concentrations in Women Delivering Preterm. Ann Nutr Metab. 2012, 61: 7-14. 10.1159/000338473.PubMed Dhobale M, Chavan P, Kulkarni A, Mehendale S, Pisal H, Joshi S: Reduced Folate, Increased Vitamin B12 and Homocysteine Concentrations in Women Delivering Preterm. Ann Nutr Metab. 2012, 61: 7-14. 10.1159/000338473.PubMed
75.
go back to reference Papadopoulou E, Stratakis N, Roumeliotaki T, Sarri K, Merlo DF, Kogevinas M, Chatzi L: The effect of high doses of folic acid and iron supplementation in early-to-mid pregnancy on prematurity and fetal growth retardation: the mother-child cohort study in Crete, Greece (Rhea study). Eur J Nutr. 2013, 52: 327-336. 10.1007/s00394-012-0339-z.PubMed Papadopoulou E, Stratakis N, Roumeliotaki T, Sarri K, Merlo DF, Kogevinas M, Chatzi L: The effect of high doses of folic acid and iron supplementation in early-to-mid pregnancy on prematurity and fetal growth retardation: the mother-child cohort study in Crete, Greece (Rhea study). Eur J Nutr. 2013, 52: 327-336. 10.1007/s00394-012-0339-z.PubMed
76.
go back to reference Shaw GM, Carmichael SL, Nelson V, Selvin S, Schaffer DM: Occurrence of low birthweight and preterm delivery among California infants before and after compulsory food fortification with folic acid. Public Health Rep. 2004, 119: 170-173.PubMedPubMedCentral Shaw GM, Carmichael SL, Nelson V, Selvin S, Schaffer DM: Occurrence of low birthweight and preterm delivery among California infants before and after compulsory food fortification with folic acid. Public Health Rep. 2004, 119: 170-173.PubMedPubMedCentral
77.
go back to reference van Eijsden M, Smits LJM, van der Wal MF, Bonsel GJ: Association between short interpregnancy intervals and term birth weight: the role of folate depletion. Am J Clin Nutr. 2008, 88: 147-153.PubMed van Eijsden M, Smits LJM, van der Wal MF, Bonsel GJ: Association between short interpregnancy intervals and term birth weight: the role of folate depletion. Am J Clin Nutr. 2008, 88: 147-153.PubMed
78.
go back to reference Nilsen RM, Vollset SE, Monsen AL, Ulvik A, Haugen M, Meltzer HM, Magnus P, Ueland PM: Infant birth size is not associated with maternal intake and status of folate during the second trimester in Norwegian pregnant women. J Nutr. 2010, 140: 572-579. 10.3945/jn.109.118158.PubMed Nilsen RM, Vollset SE, Monsen AL, Ulvik A, Haugen M, Meltzer HM, Magnus P, Ueland PM: Infant birth size is not associated with maternal intake and status of folate during the second trimester in Norwegian pregnant women. J Nutr. 2010, 140: 572-579. 10.3945/jn.109.118158.PubMed
79.
go back to reference Pastor-Valero M, Navarrete-Munoz EM, Rebagliato M, Iniguez C, Murcia M, Marco A, Ballester F, Vioque J: Periconceptional folic acid supplementation and anthropometric measures at birth in a cohort of pregnant women in Valencia, Spain. Br J Nutr. 2011, 105: 1352-1360. 10.1017/S0007114510005143.PubMed Pastor-Valero M, Navarrete-Munoz EM, Rebagliato M, Iniguez C, Murcia M, Marco A, Ballester F, Vioque J: Periconceptional folic acid supplementation and anthropometric measures at birth in a cohort of pregnant women in Valencia, Spain. Br J Nutr. 2011, 105: 1352-1360. 10.1017/S0007114510005143.PubMed
80.
go back to reference Takimoto H, Hayashi F, Kusama K, Kato N, Yoshiike N, Toba M, Ishibashi T, Miyasaka N, Kubota T: Elevated maternal serum folate in the third trimester and reduced fetal growth: a longitudinal study. J Nutr Sci Vitaminol. 2011, 57: 130-137. 10.3177/jnsv.57.130.PubMed Takimoto H, Hayashi F, Kusama K, Kato N, Yoshiike N, Toba M, Ishibashi T, Miyasaka N, Kubota T: Elevated maternal serum folate in the third trimester and reduced fetal growth: a longitudinal study. J Nutr Sci Vitaminol. 2011, 57: 130-137. 10.3177/jnsv.57.130.PubMed
81.
go back to reference Wen SW, Chen XK, Rodger M, White RR, Yang Q, Smith GN, Sigal RJ, Perkins SL, Walker MC: Folic acid supplementation in early second trimester and the risk of preeclampsia. Am J Obstet Gynecol. 2008, 198: 45-e1-7PubMed Wen SW, Chen XK, Rodger M, White RR, Yang Q, Smith GN, Sigal RJ, Perkins SL, Walker MC: Folic acid supplementation in early second trimester and the risk of preeclampsia. Am J Obstet Gynecol. 2008, 198: 45-e1-7PubMed
82.
go back to reference Bodnar LM, Tang G, Ness RB, Harger G, Roberts JM: Periconceptional multivitamin use reduces the risk of preeclampsia. Am J Epidemiol. 2006, 164: 470-477. 10.1093/aje/kwj218.PubMed Bodnar LM, Tang G, Ness RB, Harger G, Roberts JM: Periconceptional multivitamin use reduces the risk of preeclampsia. Am J Epidemiol. 2006, 164: 470-477. 10.1093/aje/kwj218.PubMed
83.
go back to reference Hernandez-Diaz S, Werler MM, Louik C, Mitchell AA: Risk of gestational hypertension in relation to folic acid supplementation during pregnancy. Am J Epidemiol. 2002, 156: 806-812. 10.1093/aje/kwf129.PubMed Hernandez-Diaz S, Werler MM, Louik C, Mitchell AA: Risk of gestational hypertension in relation to folic acid supplementation during pregnancy. Am J Epidemiol. 2002, 156: 806-812. 10.1093/aje/kwf129.PubMed
84.
go back to reference 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 Cohort. Am J Epidemiol. 2009, 169: 1304-1311. 10.1093/aje/kwp052.PubMedPubMedCentral 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 Cohort. Am J Epidemiol. 2009, 169: 1304-1311. 10.1093/aje/kwp052.PubMedPubMedCentral
85.
go back to reference Banhidy F, Dakhlaoui A, Dudas I, Czeizel AE: Birth outcomes of newborns after folic acid supplementation in pregnant women with early and late pre-eclampsia: a population-based study. in press Banhidy F, Dakhlaoui A, Dudas I, Czeizel AE: Birth outcomes of newborns after folic acid supplementation in pregnant women with early and late pre-eclampsia: a population-based study. in press
86.
go back to reference Walker MC, Finkelstein SA, White RR, Shachkina S, Smith GN, Wen SW, Rodger M: The Ottawa and Kingston (OaK) Birth Cohort: Development and Achievements. J Obstet Gynaecol Can. 2011, 33: 1124-1133.PubMed Walker MC, Finkelstein SA, White RR, Shachkina S, Smith GN, Wen SW, Rodger M: The Ottawa and Kingston (OaK) Birth Cohort: Development and Achievements. J Obstet Gynaecol Can. 2011, 33: 1124-1133.PubMed
87.
go back to reference Li Z, Ye R, Zhang L, Li H, Liu J, Ren A: Folic acid supplementation during early pregnancy and the risk of gestational hypertension and preeclampsia. Hypertension. 2013, 61: 873-879. 10.1161/HYPERTENSIONAHA.111.00230.PubMed Li Z, Ye R, Zhang L, Li H, Liu J, Ren A: Folic acid supplementation during early pregnancy and the risk of gestational hypertension and preeclampsia. Hypertension. 2013, 61: 873-879. 10.1161/HYPERTENSIONAHA.111.00230.PubMed
88.
go back to reference Timmermans S, Jaddoe VW, Silva LM, Hofman A, Raat H, Steegers-Theunissen RP, Steegers EA: Folic acid is positively associated with uteroplacental vascular resistance: The Generation R Study. Nutr Metab Cardiovasc Dis. 2011, 21: 54-61. 10.1016/j.numecd.2009.07.002.PubMed Timmermans S, Jaddoe VW, Silva LM, Hofman A, Raat H, Steegers-Theunissen RP, Steegers EA: Folic acid is positively associated with uteroplacental vascular resistance: The Generation R Study. Nutr Metab Cardiovasc Dis. 2011, 21: 54-61. 10.1016/j.numecd.2009.07.002.PubMed
89.
go back to reference Nilsen RM, Vollset SE, Rasmussen SA, Ueland PM, Daltveit AK: Folic acid and multivitamin supplement use and risk of placental abruption: a population-based registry study. Am J Epidemiol. 2008, 167: 867-874. 10.1093/aje/kwm373.PubMed Nilsen RM, Vollset SE, Rasmussen SA, Ueland PM, Daltveit AK: Folic acid and multivitamin supplement use and risk of placental abruption: a population-based registry study. Am J Epidemiol. 2008, 167: 867-874. 10.1093/aje/kwm373.PubMed
90.
go back to reference Gardosi J, Madurasinghe V, Williams M, Malik A, Francis A: Maternal and fetal risk factors for stillbirth: population based study. BMJ. 2013, 346: 1-14. 10.1136/bmj.f1. Gardosi J, Madurasinghe V, Williams M, Malik A, Francis A: Maternal and fetal risk factors for stillbirth: population based study. BMJ. 2013, 346: 1-14. 10.1136/bmj.f1.
91.
go back to reference Goh YI, Bollano E, Einarson TR, Koren G: Prenatal multivitamin supplementation and rates of pediatric cancers: a meta-analysis. Clin Pharmacol Ther. 2007, 81: 685-691. 10.1038/sj.clpt.6100100.PubMed Goh YI, Bollano E, Einarson TR, Koren G: Prenatal multivitamin supplementation and rates of pediatric cancers: a meta-analysis. Clin Pharmacol Ther. 2007, 81: 685-691. 10.1038/sj.clpt.6100100.PubMed
92.
go back to reference Milne E, Greenop KR, Bower C, Miller M, van Bockxmeer FM, Scott RJ, de Klerk NH, Ashton LJ, Gottardo NG: Armstrong BK for the Aus-CBT Consortium: maternal use of folic acid and other supplements and risk of childhood brain tumors. Cancer Epidemiol Biomarkers Prev. 2012, 21: 1933-1941. 10.1158/1055-9965.EPI-12-0803.PubMed Milne E, Greenop KR, Bower C, Miller M, van Bockxmeer FM, Scott RJ, de Klerk NH, Ashton LJ, Gottardo NG: Armstrong BK for the Aus-CBT Consortium: maternal use of folic acid and other supplements and risk of childhood brain tumors. Cancer Epidemiol Biomarkers Prev. 2012, 21: 1933-1941. 10.1158/1055-9965.EPI-12-0803.PubMed
93.
go back to reference French AE, Grant R, Weitzman S, Ray JG, Vermeulen MJ, Sung L, Greenberg M, Koren G: Folic acid food fortification is associated with a decline in neuroblastoma. Clin Pharmacol Ther. 2003, 74: 288-294. 10.1016/S0009-9236(03)00200-5.PubMed French AE, Grant R, Weitzman S, Ray JG, Vermeulen MJ, Sung L, Greenberg M, Koren G: Folic acid food fortification is associated with a decline in neuroblastoma. Clin Pharmacol Ther. 2003, 74: 288-294. 10.1016/S0009-9236(03)00200-5.PubMed
94.
go back to reference Grupp SG, Greenberg ML, Ray JG, Busto U, Lanctôt KL, Nulman I, Koren G: Pediatric cancer rates after universal folic acid fluor fortification in Ontario. J Clin Pharmacol. 2011, 51: 60-65. 10.1177/0091270010365553.PubMed Grupp SG, Greenberg ML, Ray JG, Busto U, Lanctôt KL, Nulman I, Koren G: Pediatric cancer rates after universal folic acid fluor fortification in Ontario. J Clin Pharmacol. 2011, 51: 60-65. 10.1177/0091270010365553.PubMed
95.
go back to reference Linabery AM, Johnson KJ, Ross JA: Childhood cancer incidence trends in association with us folic acid fortification (1986–2008). Pediatrics. 2012, 129: 1125-1133. 10.1542/peds.2011-3418.PubMedPubMedCentral Linabery AM, Johnson KJ, Ross JA: Childhood cancer incidence trends in association with us folic acid fortification (1986–2008). Pediatrics. 2012, 129: 1125-1133. 10.1542/peds.2011-3418.PubMedPubMedCentral
96.
go back to reference Tamura T, Goldenberg RL, Chapman VR, Johnston KE, Ramey SL, Nelson KG: Folate status of mothers during pregnancy and mental and psychomotor development of their children at five years of age. Pediatrics. 2005, 116: 703-708. 10.1542/peds.2004-2189.PubMed Tamura T, Goldenberg RL, Chapman VR, Johnston KE, Ramey SL, Nelson KG: Folate status of mothers during pregnancy and mental and psychomotor development of their children at five years of age. Pediatrics. 2005, 116: 703-708. 10.1542/peds.2004-2189.PubMed
97.
go back to reference Chatzi L, Papadopoulou E, Koutra K, Roumeliotaki T, Georgiou V, Stratakis N, Lebentakou V, Karachaliou M, Vassilaki M, Kogevinas M: Effect of high doses of folic acid supplementation in early pregnancy on child neurodevelopment at 18 months of age: the mother-child cohort ‘Rhea’ study in Crete, Greece. Public Health Nutr. 2012, 15: 1728-1736. 10.1017/S1368980012000067.PubMed Chatzi L, Papadopoulou E, Koutra K, Roumeliotaki T, Georgiou V, Stratakis N, Lebentakou V, Karachaliou M, Vassilaki M, Kogevinas M: Effect of high doses of folic acid supplementation in early pregnancy on child neurodevelopment at 18 months of age: the mother-child cohort ‘Rhea’ study in Crete, Greece. Public Health Nutr. 2012, 15: 1728-1736. 10.1017/S1368980012000067.PubMed
98.
go back to reference Roth C, Magnus P, Schjolberg S, Stoltenberg C, Suren P, McKeagle IW, Davey Smith G, Reichborn-Kjennerud T, Susser E, Davey Smith G, Reichborn-Kjennerud T, Susser E: Folic acid supplements in pregnancy and severe language delay in children. JAMA. 2011, 306: 1566-1573. 10.1001/jama.2011.1433.PubMedPubMedCentral Roth C, Magnus P, Schjolberg S, Stoltenberg C, Suren P, McKeagle IW, Davey Smith G, Reichborn-Kjennerud T, Susser E, Davey Smith G, Reichborn-Kjennerud T, Susser E: Folic acid supplements in pregnancy and severe language delay in children. JAMA. 2011, 306: 1566-1573. 10.1001/jama.2011.1433.PubMedPubMedCentral
99.
go back to reference Surén P, Roth C, Bresnahan M, Haugen M, Hornig M, Hirtz D, Lie KK, Lipkin WI, Magnus P, Reichborn-Kjennerud T, Schjølberg S, Davey Smith G, Oyen AS, Susser E, Stoltenberg C: Association between maternal use of folic acid supplements and risk of autism spectrum disorders in children. JAMA. 2013, 309: 570-577. 10.1001/jama.2012.155925.PubMedPubMedCentral Surén P, Roth C, Bresnahan M, Haugen M, Hornig M, Hirtz D, Lie KK, Lipkin WI, Magnus P, Reichborn-Kjennerud T, Schjølberg S, Davey Smith G, Oyen AS, Susser E, Stoltenberg C: Association between maternal use of folic acid supplements and risk of autism spectrum disorders in children. JAMA. 2013, 309: 570-577. 10.1001/jama.2012.155925.PubMedPubMedCentral
100.
go back to reference Centers for Disease Control and Prevention (CDC): CDC Grand Rounds: additional opportunities to prevent neural tube defects with folic acid fortification. MMWR Morb Mortal Wkly Rep. 2010, 59: 980-984. Centers for Disease Control and Prevention (CDC): CDC Grand Rounds: additional opportunities to prevent neural tube defects with folic acid fortification. MMWR Morb Mortal Wkly Rep. 2010, 59: 980-984.
101.
go back to reference U.S. Food and Drug Administration: Food standards: amendment of standards of identity for enriched grain products to require addition of folic acid. Fed Regist. 1996, 61: 8781-8797. U.S. Food and Drug Administration: Food standards: amendment of standards of identity for enriched grain products to require addition of folic acid. Fed Regist. 1996, 61: 8781-8797.
102.
go back to reference Government of Canada: Regulations amending the food and drug regulations. Canada Gazette Part II. 1998, 132: 3026-3040. Government of Canada: Regulations amending the food and drug regulations. Canada Gazette Part II. 1998, 132: 3026-3040.
103.
go back to reference Lopez-Camelo JS, Orioli IM, da Graca Dutra M, Nazer-Herrera J, Rivera N, Ojeda ME, Canessa A, Wettig E, Fontannaz AM, Mellado C, Castilla EE: Reduction of birth prevalence rates of neural tube defects after folic acid fortification in Chile. Am J Med Genet. 2005, 135A: 120-125. 10.1002/ajmg.a.30651. Lopez-Camelo JS, Orioli IM, da Graca Dutra M, Nazer-Herrera J, Rivera N, Ojeda ME, Canessa A, Wettig E, Fontannaz AM, Mellado C, Castilla EE: Reduction of birth prevalence rates of neural tube defects after folic acid fortification in Chile. Am J Med Genet. 2005, 135A: 120-125. 10.1002/ajmg.a.30651.
104.
go back to reference Chen LT, Rivera MA: The Costa Rica Experience: Reduction of NTDS following food fortification programs. Nutr Rev. 2004, 62: S40-S43.PubMed Chen LT, Rivera MA: The Costa Rica Experience: Reduction of NTDS following food fortification programs. Nutr Rev. 2004, 62: S40-S43.PubMed
105.
go back to reference 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 Africa. Birth Defects Res A Clin Mol Teratol. 2008, 82: 211-216. 10.1002/bdra.20442.PubMed 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 Africa. Birth Defects Res A Clin Mol Teratol. 2008, 82: 211-216. 10.1002/bdra.20442.PubMed
106.
go back to reference Australian Government: Cereals and cereal products. Australia New Zealand Food Standards Code. 2009, Standard 2.1.1: 1-5. Australian Government: Cereals and cereal products. Australia New Zealand Food Standards Code. 2009, Standard 2.1.1: 1-5.
107.
go back to reference Crider KS, Bailey LB, Berry RJ: Folic acid food fortification – its history, effect, concerns, and future directions. Nutrients. 2011, 3: 370-384. 10.3390/nu3030370.PubMedPubMedCentral Crider KS, Bailey LB, Berry RJ: Folic acid food fortification – its history, effect, concerns, and future directions. Nutrients. 2011, 3: 370-384. 10.3390/nu3030370.PubMedPubMedCentral
108.
go back to reference Castillo-Lancellotti C, Tur JA, Uauy R: Impact of folic acid fortification of flour on neural tube defects: a systematic review. Public Health Nutr. 2013, 16: 901-911. 10.1017/S1368980012003576.PubMed Castillo-Lancellotti C, Tur JA, Uauy R: Impact of folic acid fortification of flour on neural tube defects: a systematic review. Public Health Nutr. 2013, 16: 901-911. 10.1017/S1368980012003576.PubMed
109.
go back to reference Das JK, Salam RA, Kumar R, Bhutta ZA: Micronutrient fortification of food and its impact on woman and child health: a systematic review. Systematic Reviews. 2013, 2: 67-90. 10.1186/2046-4053-2-67.PubMedPubMedCentral Das JK, Salam RA, Kumar R, Bhutta ZA: Micronutrient fortification of food and its impact on woman and child health: a systematic review. Systematic Reviews. 2013, 2: 67-90. 10.1186/2046-4053-2-67.PubMedPubMedCentral
110.
go back to reference Busby A, Armstrong B, Dolk H, Armstrong B, Addor MC, Anneren G, Armstrong N, Baguette A, Barisic I, Berghold A, Bianca S, Braz P, Calzolari E, Christiansen M, Cocchi G, Daltveit AK, De Walle H, Edwards G, Gatt M, Gener B, Gillerot Y, Gjergja R, Goujard J, Haeusler M, Latos-Bielenska A, McDonnell R, Neville A, Olars B, Portillo I, Ritvanen A, et al: Preventing NTDS in Europe: a missed opportunity. Repr Toxicol. 2005, 20: 393-402. 10.1016/j.reprotox.2005.03.009. Busby A, Armstrong B, Dolk H, Armstrong B, Addor MC, Anneren G, Armstrong N, Baguette A, Barisic I, Berghold A, Bianca S, Braz P, Calzolari E, Christiansen M, Cocchi G, Daltveit AK, De Walle H, Edwards G, Gatt M, Gener B, Gillerot Y, Gjergja R, Goujard J, Haeusler M, Latos-Bielenska A, McDonnell R, Neville A, Olars B, Portillo I, Ritvanen A, et al: Preventing NTDS in Europe: a missed opportunity. Repr Toxicol. 2005, 20: 393-402. 10.1016/j.reprotox.2005.03.009.
111.
go back to reference Botto LD, Lisi A, Robert-Gnansia E, Erickson JD, Vollset SE, Mastroiacovo P, Botting B, Cocchi G, de Vigan C, de Walle H, Feijoo M, Irgens LM, McDonnell B, Merlob P, Ritvanen A, Scarano G, Siffel C, Metneki J, Stoll C, Smithells R, Goujard J: International retrospective cohort study of neural tube defects in relation to folic acid recommendations: are the recommendations working?. BMJ. 2005, 330: 571-578. 10.1136/bmj.38336.664352.82.PubMedPubMedCentral Botto LD, Lisi A, Robert-Gnansia E, Erickson JD, Vollset SE, Mastroiacovo P, Botting B, Cocchi G, de Vigan C, de Walle H, Feijoo M, Irgens LM, McDonnell B, Merlob P, Ritvanen A, Scarano G, Siffel C, Metneki J, Stoll C, Smithells R, Goujard J: International retrospective cohort study of neural tube defects in relation to folic acid recommendations: are the recommendations working?. BMJ. 2005, 330: 571-578. 10.1136/bmj.38336.664352.82.PubMedPubMedCentral
112.
go back to reference Wald NJ, Law MR, Morris JK, Wald DS: Quantifying the effect of folic acid. Lancet. 2001, 358: 2069-2073. 10.1016/S0140-6736(01)07104-5.PubMed Wald NJ, Law MR, Morris JK, Wald DS: Quantifying the effect of folic acid. Lancet. 2001, 358: 2069-2073. 10.1016/S0140-6736(01)07104-5.PubMed
113.
go back to reference Tolarova M, Harris J: Reduced recurrence of orofacial clefts after periconceptional supplementation with high dose folic acid and multivitamins. Teratology. 1995, 51: 71-78. 10.1002/tera.1420510205.PubMed Tolarova M, Harris J: Reduced recurrence of orofacial clefts after periconceptional supplementation with high dose folic acid and multivitamins. Teratology. 1995, 51: 71-78. 10.1002/tera.1420510205.PubMed
114.
go back to reference Czeizel AE, Timar L, Sarkozi A: Dose-dependent effect of folic acid on the prevention of orofacial clefts. Pediatrics. 1999, 104: e66-10.1542/peds.104.6.e66.PubMed Czeizel AE, Timar L, Sarkozi A: Dose-dependent effect of folic acid on the prevention of orofacial clefts. Pediatrics. 1999, 104: e66-10.1542/peds.104.6.e66.PubMed
115.
go back to reference Daly LE, Kirke PN, Molloy A, Weir DG, Scott JM: Folate levels and neural tube defects. Implications for Prevention JAMA. 1995, 274: 1698-1702.PubMed Daly LE, Kirke PN, Molloy A, Weir DG, Scott JM: Folate levels and neural tube defects. Implications for Prevention JAMA. 1995, 274: 1698-1702.PubMed
116.
go back to reference Pietrzik K, Lamers Y, Bramswig S, Prinz-Langerohl R: Calculation of red blood cell folate steady state conditions and elimination kinetics after daily supplementation with various folate forms and doses in women of childbearing age. Am J Clin Nutr. 2007, 86: 1414-1419.PubMed Pietrzik K, Lamers Y, Bramswig S, Prinz-Langerohl R: Calculation of red blood cell folate steady state conditions and elimination kinetics after daily supplementation with various folate forms and doses in women of childbearing age. Am J Clin Nutr. 2007, 86: 1414-1419.PubMed
117.
go back to reference Houghton LA, Sherwood KL, O’Connor DL: How well do blood folate concentrations predict dietary folate intakes in a sample of Canadian lactating women exposed to high levels of folate? An observational study. BMC Pregnancy Childbirth. 2007, 25: 7-25. Houghton LA, Sherwood KL, O’Connor DL: How well do blood folate concentrations predict dietary folate intakes in a sample of Canadian lactating women exposed to high levels of folate? An observational study. BMC Pregnancy Childbirth. 2007, 25: 7-25.
118.
go back to reference McLean E, de Benoist B, Allen LH: Review of the magnitude of folate and Vitamin B12 deficiencies worldwide. Food Nutr Bull. 2008, 29: S38-S51.PubMed McLean E, de Benoist B, Allen LH: Review of the magnitude of folate and Vitamin B12 deficiencies worldwide. Food Nutr Bull. 2008, 29: S38-S51.PubMed
119.
go back to reference Cocchi G, Conti L, Bravi F, Prati E, Giura F, Vitali F, Capelli M, Princivalle S, Fantini MP: Impiego di acido folico (FA) peri-concezionale: risultati dell’indagine CONER. Rome: Istituto Superiore di Sanità - ISTISAN Congressi 07/C6, 10-11. ISSN 0393–5620 Cocchi G, Conti L, Bravi F, Prati E, Giura F, Vitali F, Capelli M, Princivalle S, Fantini MP: Impiego di acido folico (FA) peri-concezionale: risultati dell’indagine CONER. Rome: Istituto Superiore di Sanità - ISTISAN Congressi 07/C6, 10-11. ISSN 0393–5620
120.
go back to reference Wilson RD, Johnson JA, Wyatt P, Allen V, Gagnon A, Langlois S, Blight C, Audibert F, Désilets V, Brock JA, Koren G, Goh YI, Nguyen P, Kapur B: Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada and The Motherrisk Program. Pre-conceptional vitamin/folic acid supplementation 2007: the use of folic acid in combination with a multivitamin supplement for the prevention of neural tube defects and other congenital anomalies. J Obstet Gynaecol Can. 2007, 29: 1003-1026.PubMed Wilson RD, Johnson JA, Wyatt P, Allen V, Gagnon A, Langlois S, Blight C, Audibert F, Désilets V, Brock JA, Koren G, Goh YI, Nguyen P, Kapur B: Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada and The Motherrisk Program. Pre-conceptional vitamin/folic acid supplementation 2007: the use of folic acid in combination with a multivitamin supplement for the prevention of neural tube defects and other congenital anomalies. J Obstet Gynaecol Can. 2007, 29: 1003-1026.PubMed
121.
go back to reference Kennedy D, Koren G: Identifying women who might benefit from higher doses of folic acid in pregnancy. Can Fam Physician. 2012, 58: 394-397.PubMedPubMedCentral Kennedy D, Koren G: Identifying women who might benefit from higher doses of folic acid in pregnancy. Can Fam Physician. 2012, 58: 394-397.PubMedPubMedCentral
122.
go back to reference Pagan K, Hou J, Goldenberg RL, Cliver SP, Tamura T: Effect of smoking on serum concentrations of total homocysteine and B vitamins in mid-pregnancy. Clin Chim Acta. 2001, 306: 103-109. 10.1016/S0009-8981(01)00402-8.PubMed Pagan K, Hou J, Goldenberg RL, Cliver SP, Tamura T: Effect of smoking on serum concentrations of total homocysteine and B vitamins in mid-pregnancy. Clin Chim Acta. 2001, 306: 103-109. 10.1016/S0009-8981(01)00402-8.PubMed
123.
go back to reference Bakker R, Timmermans S, Steegers EA, Hofman A, Jaddoe VW: Folic acid supplements modify the adverse effects of maternal smoking on fetal growth and neonatal complications. J Nutr. 2011, 141: 2172-2179. 10.3945/jn.111.142976.PubMed Bakker R, Timmermans S, Steegers EA, Hofman A, Jaddoe VW: Folic acid supplements modify the adverse effects of maternal smoking on fetal growth and neonatal complications. J Nutr. 2011, 141: 2172-2179. 10.3945/jn.111.142976.PubMed
124.
go back to reference Vanderwall CM, Tangney CC, Kwasny MJ, Gustashaw KA: Examination of circulating folate levels as a reflection of folate intakes among older adult supplement users and nonusers in the national health and nutrition examination survey 2003–2004. J Acad Nutr Diet. 2012, 112: 285-290. 10.1016/j.jada.2011.10.001.PubMed Vanderwall CM, Tangney CC, Kwasny MJ, Gustashaw KA: Examination of circulating folate levels as a reflection of folate intakes among older adult supplement users and nonusers in the national health and nutrition examination survey 2003–2004. J Acad Nutr Diet. 2012, 112: 285-290. 10.1016/j.jada.2011.10.001.PubMed
125.
go back to reference Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA: Folic acid antagonists during pregnancy and the risk of birth defects. N Engl J Med. 2000, 343: 1608-1614. 10.1056/NEJM200011303432204.PubMed Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA: Folic acid antagonists during pregnancy and the risk of birth defects. N Engl J Med. 2000, 343: 1608-1614. 10.1056/NEJM200011303432204.PubMed
126.
go back to reference Wen SW, Zhou J, Yang Q, Fraser W, Olatunbosun O, Walker M: Maternal exposure to folic acid antagonists and placenta-mediated adverse pregnancy outcomes. CMAJ. 2008, 179: 1263-1268. 10.1503/cmaj.080859.PubMedPubMedCentral Wen SW, Zhou J, Yang Q, Fraser W, Olatunbosun O, Walker M: Maternal exposure to folic acid antagonists and placenta-mediated adverse pregnancy outcomes. CMAJ. 2008, 179: 1263-1268. 10.1503/cmaj.080859.PubMedPubMedCentral
127.
go back to reference Taruscio D: Folic acid: from research to public health. Rapporti Istisan. 2004, 04/26: 1-37. Taruscio D: Folic acid: from research to public health. Rapporti Istisan. 2004, 04/26: 1-37.
128.
go back to reference McNulty B, McNulty H, Marshall B, Ward M, Molloy AM, Scott JM, Dornan J, Pentieva K: Impact of continuing folic acid after the first trimester of pregnancy: findings of a randomized trial of Folic Acid Supplementation in the Second and Third Trimesters. Am J Clin Nutr. 2013, 98: 92-98. 10.3945/ajcn.112.057489.PubMed McNulty B, McNulty H, Marshall B, Ward M, Molloy AM, Scott JM, Dornan J, Pentieva K: Impact of continuing folic acid after the first trimester of pregnancy: findings of a randomized trial of Folic Acid Supplementation in the Second and Third Trimesters. Am J Clin Nutr. 2013, 98: 92-98. 10.3945/ajcn.112.057489.PubMed
129.
go back to reference Ek J: Plasma and red cell folate in mothers and infants in normal pregnancies. Relation to birth weight. Acta Obstet Gynecol Scand. 1982, 61: 17-20.PubMed Ek J: Plasma and red cell folate in mothers and infants in normal pregnancies. Relation to birth weight. Acta Obstet Gynecol Scand. 1982, 61: 17-20.PubMed
130.
go back to reference Tamura T, Goldenberg RL, Freeberg LE, Cliver SP, Cutter GR, Hoffman HJ: Maternal serum folate and zinc concentrations and their relationships to pregnancy outcome. Am J Clin Nutr. 1992, 56: 365-370.PubMed Tamura T, Goldenberg RL, Freeberg LE, Cliver SP, Cutter GR, Hoffman HJ: Maternal serum folate and zinc concentrations and their relationships to pregnancy outcome. Am J Clin Nutr. 1992, 56: 365-370.PubMed
131.
go back to reference Fekete K, Berti C, Trovato M, Lohner S, Dullemeijer C, Souverein OW, Cetin I, Decsi T: Effect of folate intake on health outcomes in pregnancy: a systematic review and meta-analysis on birth weight, placental weight and length of gestation. Nutr J. 2012, 11: 75-10.1186/1475-2891-11-75.PubMedPubMedCentral Fekete K, Berti C, Trovato M, Lohner S, Dullemeijer C, Souverein OW, Cetin I, Decsi T: Effect of folate intake on health outcomes in pregnancy: a systematic review and meta-analysis on birth weight, placental weight and length of gestation. Nutr J. 2012, 11: 75-10.1186/1475-2891-11-75.PubMedPubMedCentral
132.
go back to reference Lassi ZS, Salam RA, Haider BA, Bhutta ZA: Folic acid supplementation during pregnancy for maternal health and pregnancy outcomes. Cochrane Database Syst Rev. 2013, CD006896-doi:10.1002/14651858.CD006896.pub2, 3 Lassi ZS, Salam RA, Haider BA, Bhutta ZA: Folic acid supplementation during pregnancy for maternal health and pregnancy outcomes. Cochrane Database Syst Rev. 2013, CD006896-doi:10.1002/14651858.CD006896.pub2, 3
133.
go back to reference Dekker GA, Sibai BM: Etiology and pathogenesis of preeclampsia: current concepts. Am J Obstet Gynecol. 1998, 179: 1359-1375. 10.1016/S0002-9378(98)70160-7.PubMed Dekker GA, Sibai BM: Etiology and pathogenesis of preeclampsia: current concepts. Am J Obstet Gynecol. 1998, 179: 1359-1375. 10.1016/S0002-9378(98)70160-7.PubMed
134.
go back to reference Wen SW, Champagne J, White RR, Coyle D, Fraser W, Smith G, Fergusson D, Walker MC: Effect of folic acid supplementation in pregnancy on preeclampsia: the folic acid clinical trial study. J Pregnancy. In press Wen SW, Champagne J, White RR, Coyle D, Fraser W, Smith G, Fergusson D, Walker MC: Effect of folic acid supplementation in pregnancy on preeclampsia: the folic acid clinical trial study. J Pregnancy. In press
135.
go back to reference Kallen B: Use of folic acid supplementation and risk for dizygotic twinning. Early Hum Dev. 2004, 80: 143-151. 10.1016/j.earlhumdev.2004.06.002.PubMed Kallen B: Use of folic acid supplementation and risk for dizygotic twinning. Early Hum Dev. 2004, 80: 143-151. 10.1016/j.earlhumdev.2004.06.002.PubMed
136.
go back to reference Berry RJ, Kihlberg R, Devine O: Impact of misclassification of in vitro fertilisation in studies of folic acid and twinning: modelling using population based Swedish vital records. BMJ. 2005, 330: 815-10.1136/bmj.38369.437789.82.PubMedPubMedCentral Berry RJ, Kihlberg R, Devine O: Impact of misclassification of in vitro fertilisation in studies of folic acid and twinning: modelling using population based Swedish vital records. BMJ. 2005, 330: 815-10.1136/bmj.38369.437789.82.PubMedPubMedCentral
137.
go back to reference Vollset SE, Gjessing HK, Tandberg A, Ronning T, Irgens LM, Baste V, Nilsen RM, Daltveit AK: Folate supplementation and twin pregnancies. Epidemiology. 2005, 16: 201-205. 10.1097/01.ede.0000152914.84962.13.PubMed Vollset SE, Gjessing HK, Tandberg A, Ronning T, Irgens LM, Baste V, Nilsen RM, Daltveit AK: Folate supplementation and twin pregnancies. Epidemiology. 2005, 16: 201-205. 10.1097/01.ede.0000152914.84962.13.PubMed
138.
go back to reference Muggli EE, Halliday JL: Folic acid and risk of twinning: a systematic review of the recent literature, July 1994 to July 2006. MJA. 2007, 186: 243-248.PubMed Muggli EE, Halliday JL: Folic acid and risk of twinning: a systematic review of the recent literature, July 1994 to July 2006. MJA. 2007, 186: 243-248.PubMed
139.
go back to reference Blatter J, Han YY, Forno E, Brehm J, Bodnar L, Celedon JC: Folate and asthma. Am J Respir Crit Care Med. 2013, 188: 12-17. 10.1164/rccm.201302-0317PP.PubMedPubMedCentral Blatter J, Han YY, Forno E, Brehm J, Bodnar L, Celedon JC: Folate and asthma. Am J Respir Crit Care Med. 2013, 188: 12-17. 10.1164/rccm.201302-0317PP.PubMedPubMedCentral
140.
go back to reference Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ: Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013, 98: 1272-1281. 10.3945/ajcn.113.065623.PubMed Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ: Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013, 98: 1272-1281. 10.3945/ajcn.113.065623.PubMed
141.
go back to reference Mills JL, Von Kohorn I, Conley MR, Zeller JA, Cox C, Williamson RE, Dufour DR: Low vitamin B-12 concentrations in patients without anemia: the effect of folic acid fortification of grain. Am J Clin Nutr. 2003, 77: 1474-1477.PubMed Mills JL, Von Kohorn I, Conley MR, Zeller JA, Cox C, Williamson RE, Dufour DR: Low vitamin B-12 concentrations in patients without anemia: the effect of folic acid fortification of grain. Am J Clin Nutr. 2003, 77: 1474-1477.PubMed
142.
go back to reference Vollset SE, Clarke R, Lewington S, Ebbing M, Halsey J, Lonn E, Armitage J, Manson JE, Hankey GJ, Spence JD, Galan P, Bonaa KH, Jamison R, Gaziano JM, Guarino P, Baron JA, Logan RF, Giovannucci EL, den Heijer M, Ueland PM, Bennett D, Collins R: Peto R, for the B-Vitamin Treatment Trialists’ Collaboration: Effects of folic acid supplementation on overall and site-specific cancer incidence during the randomised trials: meta-analyses of data on 50000 individuals. Lancet. 2013, 381: 1029-1036. 10.1016/S0140-6736(12)62001-7.PubMed Vollset SE, Clarke R, Lewington S, Ebbing M, Halsey J, Lonn E, Armitage J, Manson JE, Hankey GJ, Spence JD, Galan P, Bonaa KH, Jamison R, Gaziano JM, Guarino P, Baron JA, Logan RF, Giovannucci EL, den Heijer M, Ueland PM, Bennett D, Collins R: Peto R, for the B-Vitamin Treatment Trialists’ Collaboration: Effects of folic acid supplementation on overall and site-specific cancer incidence during the randomised trials: meta-analyses of data on 50000 individuals. Lancet. 2013, 381: 1029-1036. 10.1016/S0140-6736(12)62001-7.PubMed
Metadata
Title
Prevention of congenital malformations and other adverse pregnancy outcomes with 4.0 mg of folic acid: community-based randomized clinical trial in Italy and the Netherlands
Authors
Renata Bortolus
Fenneke Blom
Francesca Filippini
Mireille NM van Poppel
Emanuele Leoncini
Denhard J de Smit
Pier Paolo Benetollo
Martina C Cornel
Hermien EK de Walle
Pierpaolo Mastroiacovo
Publication date
01-12-2014
Publisher
BioMed Central
Published in
BMC Pregnancy and Childbirth / Issue 1/2014
Electronic ISSN: 1471-2393
DOI
https://doi.org/10.1186/1471-2393-14-166

Other articles of this Issue 1/2014

BMC Pregnancy and Childbirth 1/2014 Go to the issue