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

BMC Pregnancy and Childbirth

Pierpaolo Mastroiacovo⁷  Hermien EK de Walle¹  Martina C Cornel³  Pier Paolo Benetollo⁶  Denhard J de Smit⁵  Emanuele Leoncini⁷  Mireille NM van Poppel²  Francesca Filippini⁴  Fenneke Blom³  Renata Bortolus⁴ 

[1] Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands;Department of Public and Occupational Health, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands;Community Genetics, Department of Clinical Genetics, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands;Office for Research Promotion, Department of the Hospital Management and Pharmacy, Verona University Hospital, P.le A. Stefani, 1-37126 Verona, Italy;MediClara Projects BV, Abcoude, the Netherlands;Healthcare Directorate, Verona University Hospital, Verona, Italy;Alessandra Lisi International Centre on Birth Defects and Prematurity-ICBD, WHO Collaborating Centre, Rome, Italy

关键词: Meta-analysis;    Pre-eclampsia;    Birth weight;    Prematurity;    Prevention;    Vitamins;    Folic acid;    Birth defects;    Congenital malformations;   

Others  :  1127341
DOI  :  10.1186/1471-2393-14-166

 received in 2014-03-21, accepted in 2014-04-25,  发布年份 2014

【 摘 要 】

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.

【 授权许可】

   
2014 Bortolus et al.; licensee BioMed Central Ltd.

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