LAUSR

Background: Studies of obstetric quality of care have almost exclusively focused on severe maternal morbidity (SMM) and have rarely examined more common complications. Methods: This 2016-2018 retrospective, population-based cohort study analyzed maternal delivery outcomes at 127 Illinois hospitals. International Classification of Disease (ICD)-10 Revision codes were used to describe the incidence of SMM and route-specific complications. Poisson regression models were used to estimate the association of maternal sociodemographic, clinical, and hospital characteristics with the likelihood of coded complications. Results: Among 421,426 deliveries, the SMM rate was 1.4% overall, 0.4% for vaginal, and 2.8% for cesarean delivery. Other complications were documented for 6.9% of women with vaginal and 10.0% of women with cesarean deliveries. While SMM rates were stable, vaginal delivery complications increased 5.9% from 2016 to 2018 and cesarean delivery complications increased 13.8%. Patient age, minority race and ethnicity, high poverty level, and preexisting and pregnancy-related clinical conditions were significantly associated with each complication outcome. Higher hospital delivery volume was associated with higher route-specific complications. Discussion: SMM significantly underestimates the incidence of maternal complications. Complicated deliveries have much higher charges and length of stay, although ICD-10 coding intensity may influence incidence. New outcome measures based on more detailed clinical data and linked antepartum and postpartum care will be necessary to improve obstetric quality of care measurement.