Background: Epidemiological studies have shown that children of women with gestational diabetes have increased risk to develop early cardiovascular disease in childhood and young adulthood. GDM is associated with fetal cardiac morphological and functional changes which are mostly noted in the right ventricle, which is consistent with the dominance of the right heart late in gestation.
Objective: To evaluate fetal cardiac function by fetal echocardiography in pregnant diabetic patients including assessment of systolic function, diastolic function and their alteration in pregnant diabetic patients.
Patients and methods: This study was a prospective study that conducted on a total of 80 patients who attended outpatient clinics at Obstetrics and Gynecology Department, Al-AzharUniversityHospitals during the period from May 2020 till May 2021.  All cases had gestational age above 28 weeks, and all suffered from GDM. We measured the glycosylated hemoglobin (HbA1c) levels of the participants; the mean cut off value was 6.5%, where a level of < 6.5% indicates good glycemic control and a level of > 6.5% indicates poor glycemic control.
Results: The mean HbA1c of pregnant women with uncontrolled diabetes was significantly higher than that detected in controlled women with diabetes (6.84±0.52 % vs. 5.27±0.29 %, P<0.001). The mean age of pregnant women with controlled and uncontrolled diabetes was 26.9±3.44 and 25.62±3.96 years respectively. There were no statistically significant differences between the two groups regarding age (P=0.128). There were 17 women with controlled diabetes (42.5%) and twenty women with uncontrolled diabetes (50%) had their age ranged between (18-25) years. As regard echocardiographic assessment, measurement of ventricular myocardial free walls and interventricular septal thickness was done as a tool for evaluation of cardiac hypertrophic cardiomyopathy that occurs in fetuses of diabetic mothers. Doppler-derived modified myocardial performance index (Mod-MPI) was used to assess global overall systolic and diastolic function to display whether impairment of fetal cardiac function occurred or not. Both groups were within a comparable gestational age (between 28 and 38 weeks gestation).
Conclusion: Uncontrolled gestational diabetes mellitus in pregnant women can cause changes such as in the thickness of the ventricular wall of the fetus's heart, and cardiac diastolic dysfunction especially prolonged IVRT, which can have more severe consequences.