Maternal prepregnancy underweight reduced the risk of major isolated heart defects (OR 0.64; 95% CI 0.43-0.97), whereas overweight/obesity yielded an OR of 1.36 (95% CI 0.95-1.93).
Case-Control (n=4,078)
Effect estimate: OR 0.64 (95% CI 0.43-0.97)
To determine the relation between having an infant with a major heart defect and a mother's prepregnancy weight, we compared 1,049 Atlanta-area women who gave birth to liveborn or stillborn infants, each with a major heart defect, with 3,029 Atlanta-area women who gave birth to infants without birth defects. The infants of control women were randomly selected from birth certificates and were frequency-matched to the case group by race, birth hospital, and birth period from 1968 through 1980. After excluding diabetic mothers and adjusting for potential confounders, compared with average-weight women (body mass index 19.9--22.7), we found that underweight women (body mass index 26) (OR = 1.36; 95% CI = 0.95--1.93). Using average-weight women who did not take periconceptional multivitamins as the reference group, periconceptional multivitamin use was associated with a reduced OR for isolated heart defects among average-weight women (OR = 0.61, 95% CI = 0.36--0.99) and underweight women but not among overweight or obese women (OR = 1.69, 95% CI = 0.69--3.84).
Watkins et al. (Sun,) conducted a case-control in Congenital Heart Defects (n=4,078). Underweight (BMI <16.5) or overweight/obese (BMI >26) prepregnancy weight vs. Average-weight women (BMI 19.9-22.7) was evaluated on Major isolated heart defect (OR 0.64, 95% CI 0.43-0.97). Maternal prepregnancy underweight reduced the risk of major isolated heart defects (OR 0.64; 95% CI 0.43-0.97), whereas overweight/obesity yielded an OR of 1.36 (95% CI 0.95-1.93).