Maternal gestational diabetes and congenital heart defects in infants

Abstract

Background A number of previous studies have reported that maternal pregestational and, less consistently, gestational diabetes mellitus are associated with increased risk of birth defects. This study examined the relationship between maternal gestational diabetes and risk of congenital heart defects (CHDs) in infants. Methods Case and control subjects were born between 1999 through 2005 and enrolled in Kaunas Birth Defects Case–Control Study. Information was obtained through a telephone interview from parents of 187 case infants with CHDs and randomly selected parents of 643 control infants without any malformations. Multivariate logistic regression was used to estimate odds ratio (OR) and 95% confidence intervals (CIs) while controlling for potential confounders. Results In this study, 11.8% of the cases and 3.9% of the controls were born to mothers with gestational diabetes. Among case infants of diabetic mothers, 60.0% had a simple heart defects and the most frequent diagnosis was septal heart defect. In the univariate analysis, maternal gestational diabetes was associated with 3-fold increased risk of CHDs (OR 3.28, 95% CI = 1.77–6.07) (P < 0.0001). In multivariate logistic regression analysis, adjustment for maternal age, education, social status, cigarette smoking during the month before pregnancy to the end of the 1st trimester and folate intake during the 3rd through 8th weeks of pregnancy did not change the relationship, although the OR decreased but remained statistically significant. Our results showed that an adjusted OR for mothers with gestational diabetes to deliver newborn with CHDs was 2.97 (95% CI = 1.53–5.76) (P < 0.001). Conclusions Maternal gestational diabetes was significantly associated with CHDs in infants.