The effect of maternal obesity on outcomes in patients undergoing tertiary or higher cesarean delivery

Objective: To estimate the association between maternal obesity and adverse outcomes in patients without placenta previa or accreta undergoing a tertiary or higher cesarean delivery. Study design: Retrospective cohort of patients cared for by a single MFM practice undergoing a tertiary or higher cesarean delivery from 2005 to 2013. Patients attempting vaginal delivery and patients with placenta accreta and/or placenta previa were excluded. We estimated the association of maternal obesity (prepregnancy BMI≥30kg/m) and maternal outcomes. The primary outcome was a composite of severe maternal morbidity (uterine rupture, hysterectomy, blood transfusion, cystotomy requiring repair, bowel injury requiring repair, intensive care unit admission, thrombosis, re-operation, or maternal death). Results: Three hundred and forty four patients met inclusion criteria, 73 (21.2%) of whom were obese. The composite outcome was significantly higher in the obese group (6.8% versus 1.8%, p=0.024, aOR 4.36, 95% CI 1.21, 15.75). The incidence of several individual adverse outcomes were also increased in obese women, including blood transfusion (4.1% versus 0.7%, p=0.033, aOR 7.36, 95% CI 1.19, 45.34), wound separation or infection (20.5% versus 5.9%, p<0.001, aOR 4.05, 95% CI 1.75, 9.36) and 1-min Apgar score less than 7 (6.8% versus 1.9%, p=0.024, aOR 4.40, 95% CI 1.21, 15.94). Conclusions: In patients undergoing a tertiary or higher cesarean delivery without placenta previa or accreta, obesity increases the risk of adverse outcomes. Obese patients are at risk for blood transfusion, low 1-min Apgar scores and postoperative wound complications.