Are Baseline Elevations in Reactive Non-Stress Testing of Diabetic Mothers an Indicator of Fetal Compromise? [4B

Abstract

INTRODUCTION: To determine if baseline fetal tachycardia in reactive non-stress test (NST) is an indicator of fetal compromise in diabetic pregnancies. METHODS: Retrospective analysis of 145 diabetic mothers including gestational and pregestational diabetics from 2013-2016. Demographics included age, BMI, race, and gestational age. We reviewed the NST of patients >34 weeks of gestation and within 7 days of delivery. Baseline fetal heart rate (FHR) and the presence of 15x15mm accelerations were noted. Outcome measures included mode and indications for delivery. RESULTS: Of 145 diabetic patients, 55 patients had a baseline >150bpm. 47 of them had reactive tracings. Of those 47 patients, 35 underwent cesarean deliveries (C/S) (74.4%). Two patients with baseline tachycardia were diagnosed with IUFD on subsequent testing. 17 of 47 C/S performed were for non-reassuring tracing (36.17%). In comparison, 92 of 145 diabetic patients had baseline FHR < 150 bpm. 68 of 92 patients had reactive tracings. Of these 68 patients, 40 underwent C/S (58.82%), 8 were for non-reassuring fetal heart tracing (11.76%). The C/S rate for non-reassuring fetal heart tracing was significantly higher in the diabetics with elevated baseline FHR and reactive tracings in comparison to those with baseline FHR < 150bpm and reactive tracings, P < 0.05. CONCLUSION: The C/S rate secondary to non-reassuring fetal heart tracings was significantly higher in diabetics with elevated baseline FHR than those with baseline FHR < 150bpm even in the setting of a reactive tracing. This may be clinically relevant in antenatal testing of diabetic mothers as it implies that elevation in baseline heart rate may indicate fetal jeopardy.