545 Completion of fetal echocardiogram (FE) in the obese parturient

Abstract

Maternal obesity is a risk factor for fetal complications including fetal cardiac anomalies, but also decreases detection of anomalies. Thus, our objective was to evaluate completion rates of fetal echocardiography (FE) in patients with obesity. Retrospective review of all FE ultrasound (US) studies at an AIUM fetal echo accredited single academic center from2016 to 2019. Patients were stratified by pre-pregnancy body mass index (BMI) into normal weight (NW) and Class I, II and III obesity. Ten key cardiac structures were defined as critical for complete FE. The percentage of views completed on Level II anatomic US and first FE were compared between groups. Primary outcome was percentage of views obtained by the conclusion of initial FE, compared between groups, with secondary outcome of number of follow up examinations needed. Data compared by ANOVA with P<0.05 considered significant. A total of 749 patients underwent 899 FEs. Completion percentage differed significantly between groups (NW- 84%, Class I 80%, Class II 80%, Class III 77%, P=.001). There were also significantly more follow up FE scans (NW 1.83 ±0.87, Class I 2.26 ±1.31, Class II 2.21±1.01, Class III 3.57±2.06; P<.0001). Increasing BMI is associated with decreased visualization of fetal cardiac structures by the conclusion of initial FE and an increase in total ultrasounds needed even at a high-quality academic FE ultrasound unit. Given the increasing rate of maternal obesity, continued efforts to improve technique, technology and potentially to adjust timing of initial ultrasound evaluation should be explored.