Fetal Epicardial Fat Thickness: Can It Serve as a Sonographic Screening Marker for Gestational Diabetes Mellitus?

Background: Gestational diabetes mellitus (GDM) is defined as the new onset of impairment in carbohydrate tolerance during pregnancy. The aim of the current study was to define fetal epicardial fat thickness (fEFT) changes that developed before 24 weeks of gestation, to evaluate the diagnostic effectiveness of fEFT in predicting GDM diagnosis, and to correlate fEFT values with hemoglobin A1C (HbA1C) values. Methods: The study included a total of 60 GDM patients and 60 control subjects. A record consisted of fEFT measurements, maternal body mass index, maternal subcutaneous fat thickness, and fetal subcutaneous fat thickness during sonographic screening performed at 18-22 gestational weeks. Fetal abdominal circumference (AC) values, estimated fetal weight (EFW), and fetal gender were also recorded. Results: The median fEFT measurement of the whole study population was 0.9 +/- 0.21 mm; 1.05 +/- 0.21 mm in the GDM patients, and 0.8 +/- 0.15 mm in the control group. The median fEFT values of the GDM patients were significantly higher than those of the control group (P < 0.01). According to the correlation analysis results, a strong positive correlation was determined between the fEFT and HbA1C values (r = 0.71, P < 0.01), gestational week of the fetus (r = 0.76, P = P < 0.01), AC (r = 0.81, P < 0.01), and EFW (r = 0.71, P < 0.01). According to the receiver operating characteristic analysis results, a fEFT value of > 0.95 can predict GDM diagnosis with sensitivity of 65% and specificity of 88% (odds ratio = 13). Conclusion: fEFT values are increased in GDM cases, and the increase can be detected earlier than 24 weeks of gestation. fEFT values are positively correlated with HbA1C values and can serve as an early predictor for GDM diagnosis.