Prospective evaluation of ultrasonographic fetal cardiac morphometry and functions in the third trimester of pregnancies with gestational diabetes mellitus.

Objective: This study aimed to compare cardiac morphological and functional changes in fetuses of patients with diet-regulated gestational diabetes mellitus (GDM-A1), insulin-regulated GDM (GDM-A2), and a control group.

Method: A prospective cohort study included pregnant women aged 18-40 years with singleton pregnancies. Fetal biometric, cardiac morphological, and functional measurements were recorded using Z-scores at 34-37 weeks of gestation.

Results: The study included 87 patients. Both right and left ventricular wall thicknesses were significantly different between the three groups (p < 0.001 and p < 0.001, respectively). Z-scores of the mitral valve, left and right EDD were significantly lower in GDM-A1 and GDM-A2 groups compared to the control group (p < 0.001, p < 0.001, p = 0.002, respectively). Right and left ventricular areas were decreased only in GDM-A2 group compared to the control group (p = 0.003 and p = 0.001, respectively). MPI and IVRT values were also significantly higher in the same groups (p = 0.016, p < 0.001, respectively).

Conclusion: Gestational diabetes increased IVS and ventricular wall thicknesses in both right and left ventricles, irrespective of whether it was controlled by diet or insulin. Cardiac functional changes were observed in the GDM-A2 group.