408 Use of decelerated abdominal circumference growth velocity (ACGV) in diabetic pregnancies

Abstract

Fetal growth restriction (FGR) is associated with significant perinatal morbidity and mortality. FGR is a known complication of diabetes in pregnancy. A small fetal abdominal circumference can predict the development of FGR and other adverse outcomes. Our objective was to determine if a slowing of the AC growth velocity over time (decelerated AC growth velocity, dACGV) is associated with adverse pregnancy outcomes in patients with diabetes in pregnancy. A retrospective cohort of 312 patients with pre-gestational diabetes (PGD) or gestational diabetes mellitus (GDM) with ultrasounds between 19w0d – 21w6d and 35w0d – 36w6d from 2013-2019 were collected. ACs at these intervals were used to calculate ACGV. ACGV ≤10th percentile was considered decelerated. Third trimester estimated fetal weight (tEFW)≤10th percentile was used as comparison. Chi square tests or Fisher’s exact tests were used for categorical variables. Of 312 patients included, 26 (8.3%) had dAGCV. A total of 39.4% had PGD and 60.6% had GDM. dACGV was not predictive of small for gestational age (SGA). However, dACGV was associated with increased risk of operative vaginal delivery [odds ratio (OR) 6.5, 95% confidence interval (CI) 2.1, 20.5], while comparable tEFW did not predict this outcome. Patients with dACGV were less likely to be using insulin compared to those with a normal ACGV (OR 0.2, 95% CI 0.1,0.6). Decelerated abdominal circumference growth velocity did not predict SGA in this diabetic cohort. However, dACGV was associated with a higher risk of operative vaginal delivery. This finding may be helpful in counseling patients with diabetes as they approach delivery.