The purpose of this study was to assess fetal cardiac function in normal fetuses (control group) compared to those who are exposed to gestational diabetes mellitus using different echocardiographic measurements, and to explore the application of left atrial shortening fraction in determination of fetal diastolic function with gestational diabetes mellitus.

A total of 50 women with gestational diabetes and 50 women with a healthy pregnancy were included in the study. Fetal echocardiography was performed and structural as well as functional fetal cardiac parameters were measured. Data were compared between with or without fetal myocardial hypertrophy and the control group.

In the study group, out of 50 fetuses of gestational diabetic mothers, 18 had myocardial hypertrophy and 32 had normal septal thickness. Gestational age at time of examination did not differ significantly between the control and gestational diabetes group (p = 0.55). Mitral E/A ratio was lower in gestational diabetes group as compared to the control (p < 0.001). Isovolumetric relaxation and contraction times and myocardial performance index were greater in fetuses of gestational diabetic mothers (p < 0.001). In fetuses of gestational diabetic mothers with myocardial hypertrophy, left atrial shortening fraction was lower as compared to those without myocardial hypertrophy and those of the control group (p < 0.001).

The results of this study suggest that fetuses of gestational diabetic mothers have altered cardiac function even in the absence of septal hypertrophy, and that left atrial shortening fraction can be used as a reliable alternate parameter in the assessment of fetal diastolic function.