Presentations

Abstract

Introduction: Inadequate glucose control during pregnancy, as seen in women with pregestational diabetes, leads to excess insulin production in the neonate, often resulting in detrimental neonatal outcomes and abnormalities. Ultrasound can be used to assess fetal growth abnormalities in individuals with diabetes, such as fetal liver volumes. The goal of our study was to determine if increased fetal liver volumes are observed in patients with diabetes compared to controls and to assess if increased liver volumes result in elevated transcutaneous bilirubin (TcB) levels in the newborn.

Methods: This was a single-center, prospective case-control study. Singleton pregnancies were consented for ultrasound (US) in the third trimester, between 30 and 34 weeks. Fetal biometry and three-dimensional (3D) fetal abdominal volumes were collected at each US visit. The fetal liver volume (FLV) was calculated from the 3D abdominal volumes using the standard VOCAL technique. Descriptive statistics were calculated for all study variables. The independent t-test and chi-square test for independence were performed where appropriate. All hypothesis testing was carried out at the 95% significance level, unless otherwise specified, with a P-value of <0.05 accepted as statistically significant.

Results: Of the 66 pregnancies enrolled in the study, 22 (33%) had pregestational diabetes, and 44 (66%) did not. Cases were more likely to have chronic hypertension (8/22 [38.1%] vs. 1/44 [2.3%], P <0.001) and a higher BMI (35 vs. 25, P <0.001). No other significant differences were noted between the groups. Fetal liver volumes were found to be larger on average in patients with diabetes compared to controls (115.88 cm3 vs. 114.29 cm3).

Conclusion: Pregnancies affected by pregestational diabetes are more likely to experience macrosomia, with fetal liver volume contributing significantly to the abdominal circumference. Our study showed that liver volumes in patients with diabetes, compared to controls, were on average larger. However, the study may be underpowered to detect a significant difference. Other components of the abdominal circumference, including abdominal fat mass, could contribute to macrosomia in pregnancies affected by diabetes. Further prospective studies are needed to assess the clinical significance of these findings in newborns.