MATERNAL PERICONCEPTIONAL USE OF MULTIVITAMINS AND REDUCED RISK FOR CONOTRUNCAL HEART-DEFECTS AND LIMB DEFICIENCIES AMONG OFFSPRING

We investigated whether a woman's periconceptional use of a multivitam in containing folic acid was associated with a reduced risk for delive ring offspring with a conotruncal heart defect or a limb deficiency. D ata were derived from a population-based case-control study of fetuses and liveborn infants with conotruncal or limb defects among a 1987-88 cohort of births in California. Telephone interviews were conducted w ith mothers of 207 (87.0% of eligible) conotruncal cases, 178 (82.0%) limb defect cases, and of 481 (76.2%) randomly selected liveborn nonma lformed control infants. were observed for of multivitamins containing folic acid from one month before until two months after conception. O dds ratios and 95% confidence intervals for any compared to no multivi tamin use were 0.70 (0.46-1.1) for conotruncal defects and O.64 (0.41- 1.0) for limb defects. Controlling for maternal race/ethnicity, age, e ducation, gravidity, alcohol use, and cigarette use resulted in a furt her reduction to the odds ratio for conotruncal defects, 0.53 (0.34-0. 85), but not for limb defects. Among non-vitamin using women, consumpt ion of containing folic acid was associated with reduced risks for bot h defects. Women who take multivitamins have 30-35% lower risk of deli vering offspring with either conotruncal or limb defects. This associa tion may not be attributable to folic acid specifically, but may be a consequence of other multivitamin components, or some unknown behavior s that highly correlate with regular use of a multivitamin. However, s hould the association prove causal, it offers an important opportunity for preventing thousands of serious birth defects. (C) 1995 Wiley-Lis s, Inc.