Cardiac Malformations in Fetuses of Gestational and Pre Gestational Diabetic Mothers

Objective: 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.
Methods: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.
Findings: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).
Conclusion: 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.

Keywords
Congenital Heart Disease; Diabetes Mellitus; Gestational Diabetes Mellitus