Y Ingrid Goh1, Enkelejd Bollano2, Thomas R Einarson1, Gideon Koren3. 1. Department of Pharmaceutical Sciences, University of Toronto, Toronto ON; The Motherisk Program, Division of Clinical Pharmacology/Toxicology, The Hospital for Sick Children, Toronto ON. 2. The Motherisk Program, Division of Clinical Pharmacology/Toxicology, The Hospital for Sick Children, Toronto ON. 3. Department of Pharmaceutical Sciences, University of Toronto, Toronto ON; The Motherisk Program, Division of Clinical Pharmacology/Toxicology, The Hospital for Sick Children, Toronto ON; Faculty of Medicine, University of Toronto, Toronto ON; lvey Chair in Molecular Toxicology, University of Western Ontario, London ON; Department of Medicine, University of Western Ontario, London ON.
Abstract
BACKGROUND: The use of folic acid-fortified multivitamin supplements has long been associated with decreasing the risk of neural tube defects. Several studies have also proposed the effectiveness of these supplements in preventing other birth defects; however, such effects have never been systematically examined. OBJECTIVE: We conducted a systematic review and meta-analysis to evaluate the protective effect of folic acid-fortified multivitamin supplements on other congenital anomalies. METHODS: We searched Medline, PubMed, EMBASE, Toxline, Healthstar, and Cochrane databases for studies describing the outcome of pregnancies in women using multivitamin supplements that were published in all languages from January 1966 to July 2005. The references from all collected articles were reviewed for additional articles. Two independent reviewers who were blinded to the source and identity of the articles extracted data based on predetermined inclusion and exclusion criteria. Using a random effects model, rates of congenital anomalies in babies born to women who were taking multivitamin supplements were compared with rates in the offspring of controls who were not. RESULTS: From the initial search, 92 studies were identified; 41 of these met the inclusion criteria. Use of multivitamin supplements provided consistent protection against neural tube defects (random effects odds ratio[OR] 0.67, 95% confidence intervals [95% CI] 0.58-0.77 in case control studies; OR 0.52, 95% CI 0.39-0.69 in cohort and randomized controlled studies), cardiovascular defects (OR 0.78, 95% CI 0.67-0.92 in case control studies; OR 0.61, 95% CI 0.40-0.92 in cohort and randomized controlled studies), and limb defects (OR 0.48, 95% CI 0.30-0.76 in case control studies; OR 0.57, 95% CI 0.38-0.85 in cohort and randomized controlled studies). For cleft palate, case control studies showed OR 0.76 (95% CI 0.62-0.93), and cohort and randomized controlled studies showed OR 0.42 (95% CI 0.06-2.84); for oral cleft with or without cleft palate, case control studies showed OR 0.63 (95% CI 0.54-0.73), and cohort and randomized controlled studies showed OR 0.58 (95% CI 0.28-1.19); for urinary tract anomalies, case control studies showed OR 0.48 (95% CI 0.30-0.76), and cohort and randomized controlled studies showed OR 0.68 (95% CI 0.35-1.31); and for congenital hydrocephalus case control studies showed OR 0.37 (95% CI 0.24-0.56), and cohort and randomized controlled studies showed OR 1.54 (95% CI 0.53-4.50). No effects were shown in preventing Down syndrome, pyloric stenosis, undescended testis, or hypospadias. CONCLUSION: Maternal consumption of folic acid-containing prenatal multivitamins is associated with decreased risk for several congenital anomalies, not only neural tube defects. These data have major public health implications, because until now fortification of only folic acid has been encouraged. This approach should be reconsidered.
BACKGROUND: The use of folic acid-fortified multivitamin supplements has long been associated with decreasing the risk of neural tube defects. Several studies have also proposed the effectiveness of these supplements in preventing other birth defects; however, such effects have never been systematically examined. OBJECTIVE: We conducted a systematic review and meta-analysis to evaluate the protective effect of folic acid-fortified multivitamin supplements on other congenital anomalies. METHODS: We searched Medline, PubMed, EMBASE, Toxline, Healthstar, and Cochrane databases for studies describing the outcome of pregnancies in women using multivitamin supplements that were published in all languages from January 1966 to July 2005. The references from all collected articles were reviewed for additional articles. Two independent reviewers who were blinded to the source and identity of the articles extracted data based on predetermined inclusion and exclusion criteria. Using a random effects model, rates of congenital anomalies in babies born to women who were taking multivitamin supplements were compared with rates in the offspring of controls who were not. RESULTS: From the initial search, 92 studies were identified; 41 of these met the inclusion criteria. Use of multivitamin supplements provided consistent protection against neural tube defects (random effects odds ratio[OR] 0.67, 95% confidence intervals [95% CI] 0.58-0.77 in case control studies; OR 0.52, 95% CI 0.39-0.69 in cohort and randomized controlled studies), cardiovascular defects (OR 0.78, 95% CI 0.67-0.92 in case control studies; OR 0.61, 95% CI 0.40-0.92 in cohort and randomized controlled studies), and limb defects (OR 0.48, 95% CI 0.30-0.76 in case control studies; OR 0.57, 95% CI 0.38-0.85 in cohort and randomized controlled studies). For cleft palate, case control studies showed OR 0.76 (95% CI 0.62-0.93), and cohort and randomized controlled studies showed OR 0.42 (95% CI 0.06-2.84); for oral cleft with or without cleft palate, case control studies showed OR 0.63 (95% CI 0.54-0.73), and cohort and randomized controlled studies showed OR 0.58 (95% CI 0.28-1.19); for urinary tract anomalies, case control studies showed OR 0.48 (95% CI 0.30-0.76), and cohort and randomized controlled studies showed OR 0.68 (95% CI 0.35-1.31); and for congenital hydrocephalus case control studies showed OR 0.37 (95% CI 0.24-0.56), and cohort and randomized controlled studies showed OR 1.54 (95% CI 0.53-4.50). No effects were shown in preventing Down syndrome, pyloric stenosis, undescended testis, or hypospadias. CONCLUSION: Maternal consumption of folic acid-containing prenatal multivitamins is associated with decreased risk for several congenital anomalies, not only neural tube defects. These data have major public health implications, because until now fortification of only folic acid has been encouraged. This approach should be reconsidered.
Authors: Carl L Keen; Janet Y Uriu-Adams; Anatoly Skalny; Andrei Grabeklis; Sevil Grabeklis; Kerri Green; Lyubov Yevtushok; Wladimir W Wertelecki; Christina D Chambers Journal: Biofactors Date: 2010 Mar-Apr Impact factor: 6.113
Authors: Mei Chung; Ethan M Balk; Stanley Ip; Gowri Raman; Winifred W Yu; Thomas A Trikalinos; Alice H Lichtenstein; Elizabeth A Yetley; Joseph Lau Journal: Am J Clin Nutr Date: 2009-02-25 Impact factor: 7.045
Authors: Teun van der Bom; A Carla Zomer; Aeilko H Zwinderman; Folkert J Meijboom; Berto J Bouma; Barbara J M Mulder Journal: Nat Rev Cardiol Date: 2010-11-02 Impact factor: 32.419
Authors: Philip A May; Kari J Hamrick; Karen D Corbin; Julie M Hasken; Anna-Susan Marais; Lesley E Brooke; Jason Blankenship; H Eugene Hoyme; J Phillip Gossage Journal: Reprod Toxicol Date: 2014-02-22 Impact factor: 3.143
Authors: Cynthia K Colapinto; Deborah L O'Connor; Margaret Sampson; Brock Williams; Mark S Tremblay Journal: J Public Health (Oxf) Date: 2015-07-09 Impact factor: 2.341