Association of Maternal Obesity With Maternal and Neonatal Outcomes in Cases of Uterine Rupture.

To describe the risk of adverse outcomes associated with uterine rupture in the setting of maternal obesity.

This was a retrospective cohort analysis of singleton nonanomalous neonates born after uterine rupture between 34 and 42 weeks of gestation. We derived data from the U.S. Natality Database from 2011 to 2014. Maternal prepregnancy body mass index (BMI) was categorized according to the World Health Organization classification. The rates of neonatal and maternal complications were calculated for each BMI class. Multivariable logistic regression analysis was used to estimate the risks of these complications among obese pregnancies compared with normal-weight pregnancies.

There were 3,942 cases of uterine rupture identified among 15,860,954 births (0.02%) between 2011 and 2014. Of these, 2,917 (74%) met inclusion criteria for analysis. There was an increased risk of low 5-minute Apgar score (22.9% compared with 15.9%; adjusted odds ratio [OR] 1.49 [1.19-1.87]), neonatal intensive care unit admission (31% compared with 24.6%; adjusted OR 1.51 [1.23-1.85]), and seizure (3.7% compared with 1.9%; adjusted OR 1.80 [1.05-3.10]) in obese compared with normal-weight pregnancies. The rate of prolonged assisted ventilation was 8.5% compared with 6.2% (P=.13), which, after adjustment for confounders, was a statistically significant difference (adjusted OR 1.47 [1.05-2.07]). The rate of neonatal death was similar (12.4 compared with 6.5/1,000 births; adjusted OR 2.03 [0.81-5.05]). The rates of various maternal complications were similar between groups.

In the setting of uterine rupture, maternal obesity moderately increases the risks of low Apgar score, neonatal intensive care unit admission, prolonged ventilation, and seizure. Risk of maternal complications and the risk of neonatal death, however, are similar to risks in patients of normal BMI.