Effects of gestational diabetes mellitus on fetal cardiac morphology and function

Hyperglycemic conditions are known to be related to fetal cardiac remodelling, which can affect cardiac function. Previous studies have shown that fetuses born from mothers with gestational diabetes (GDM) exhibit reduced cardiac function and a globular morphology. However, previous studies have not adequately accounted for the potential impact of underlying maternal conditions or other pregnancy complications that may also affect the fetal heart during pregnancy. We evaluated the effect of GDM on fetal cardiac morphology and function while adjusting for other underlying diseases. This prospective study included mid-trimester pregnant women who take antenatal care at Korea University Guro Hospital. Fetal cardiac variables were checked by Fetal HQ and cardiac shape, contractility and function were calculated. Echocardiographic parameters were compared between GDM fetuses and non-GDM fetuses. Fetal cardiac functional ultrasound was performed on 153 pregnant women, of whom 18 were diagnosed with GDM. After adjusting for overt diabetes, hypertension before pregnancy, pregnancy-related hypertensive disorder, and maternal pre-pregnancy BMI, fetuses of mothers with GDM exhibited decreased global sphericity index, which represents a more globular shape. Right ventricular functional indices, such as tricuspid annular plane systolic excursion, global longitudinal strain were reduced in fetuses of mothers with GDM compared with control. GDM is associated with a reduction of fetal cardiac function, mainly in fetal right ventricular function, compared to controls, even after adjusting for other underlying diseases.