Cardiac malformations in fetuses of gestational and pre gestational diabetic mothers

In this study we aimed to determine the prevalence of cardiac malformations in fetuses of Iranian diabetic mothers with pre-gestational and gestational diabetes mellitus (GDM) and to find the patterns of different cardiac malformations.

One-hundred and seventy diabetic pregnant women (68 preGDM and 102 GDM) (mean age: 32.17±4.8 years) and 85 healthy controls (mean age: 31.35±4.55 years) were recruited from September 2008 to July 2012. Fetal echocardiography was performed to assess cardiac malformation. In order to study major factors that may affect the results, a complete history was obtained.

Fetal echocardiography was performed at mean gestational age of 24.7±5.4 and 20.27±3.9 weeks in diabetic patients and control group, respectively. Fifteen (8.8%) fetuses of diabetic mothers were detected to have cardiac malformations compared with 1 (1.17%) fetus in control group (OR: 8.13, 95%CI: 1.1-62.61, P-value=0.02). Hypertrophic cardiomyopathy noted as the most common cardiac malformation occurred in 6 out of 15 (40%) fetuses, and was found significantly more common in pre-GDM compared to GDM group (7.4% vs 1%, P-value =0.04). Despite the higher incidence of cardiac malformation in pre-GDM compared to GDM group, the difference was not significant. Further, no significant association was observed between the variables including; parity, diabetic regimen, parents' consanguinity, maternal history of hypertension or hypothyroidism and occurring cardiac malformations (P-value>0.05).

In this study we detected cardiac malformations in 8.8% of our diabetic referrals. The result of the present study shows that screening diabetic mothers for fetal cardiac malformations could be beneficial.