DOES PERICONCEPTIONAL MULTIVITAMIN USE REDUCE THE RISK FOR LIMB DEFICIENCY IN OFFSPRING

There is accumulating evidence that periconceptional multivitamin use may prevent the occurrence of some birth defects other than neural tub e defects. Using data from the population-based Atlanta Birth Defects Case-Control Study, we investigated the possible association between p ericonceptional multivitamin use and the occurrence of limb deficiency . We examined the periconceptional use of multivitamins among mothers of 117 babies with nonsyndromic limb deficiency who were liveborn or s tillborn to residents of metropolitan Atlanta from 1968 to 1980 and am ong mothers of 3,029 control babies born without birth defects who wer e randomly selected through birth certificates. We found that children whose mothers were periconceptional multivitamin users had a lower ri sk of having a limb deficiency [odds ratio (OR) = 0.47; 95% confidence interval (CI) = 0.23-0.97]. This protective effect, however, was most ly seen for transverse limb deficiency (OR = 0.30; 95% CI = 0.07-1.32) and not for longitudinal deficiency (including preaxial and postaxial deficiencies; OR = 1.03; 95% CI = 0.17-4.30). Adjustment for potentia l confounding factors did not change these findings. We found a trend of decreasing risk for all transverse limb deficiencies with earlier v itamin use. These data indicate that mothers' periconceptional multivi tamin use may reduce the risk for some types of limb deficiency among their offspring. In addition, because we did not find the protective e ffect for all types of limb deficiency, the data may also indicate cau sal heterogeneity of limb deficiencies.