561: Neonatal outcomes in obese women undergoing cesarean delivery for fetal heart rate tracing abnormalities

Abstract

To investigate whether there is an association between maternal obesity and adverse neonatal outcomes and operative time in women undergoing cesarean delivery for a category 2 or 3 fetal heart rate (FHR) tracing. We conducted a retrospective chart review of women who delivered at the University of Virginia Medical Center between 2012 and 2015. Women were included if they delivered a nonanomalous singleton fetus at term by primary cesarean delivery with a category 2 or 3 FHR tracing as an indication for delivery. Operative details, maternal medical and sociodemographic history, and neonatal outcomes were collected by chart review. Body mass index (BMI) was examined as a categorical exposure (BMI 18.5 - 24.99, 25 - 29.99, and ≥30 kg/m2). The adverse neonatal outcome was a composite outcome defined as Apgar score <7 at 5 minutes, arterial cord pH <7.1 and/or base deficit ≥12, admission to the NICU, need for immediate neonatal resuscitation beyond bulb suction and stimulation, or hospitalization for longer than 3 days. Logistic regression was used for univariate and multivariable analyses for the composite outcome. The total operative time, and times from skin incision to hysterotomy, and hysterotomy to delivery were examined using linear regression. 285 mother-neonate pairs were included. Maternal BMI was not associated with adverse neonatal outcomes in univariate analysis (p=0.85). Magnesium sulfate administration, illicit drug or narcotic use, and rupture of membranes (ROM) for 12-24 hours were associated with adverse neonatal outcomes (p<0.05). After adjusting for magnesium sulfate use, drug use, ROM, and pregnancy related hypertension in multivariable analysis, there remained no difference in rates of neonatal adverse outcomes among different BMI groups (p=0.50, Table 1). Displayed in Figure 1, the total operative time had a linear association with maternal BMI (B=3.03; 95% CI: 1.88-4.18) as did the time from skin incision to hysterotomy (B=1.15; 95% CI: 0.85, 1.46), but not time from hysterotomy to delivery (B=0.09; 95% CI: -0.01, 0.18). For women undergoing primary cesarean delivery for category 2 or 3 fetal heart rate tracings, obesity was associated with increased operative times but not with increased rates of adverse neonatal outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)