345 Association between hospital-level cesarean delivery rates and maternal and neonatal morbidity

Abstract

The “optimal” cesarean delivery (CD) rate is unknown. Prior studies have largely compared maternal and neonatal mortality to propose CD rate targets. The objective of this study was to compare CD rates among US hospitals with widely reported measures of maternal and neonatal morbidity. This is a cross-sectional study using the 2016 Nationwide Readmissions Database. The primary outcomes were maternal and neonatal morbidity. Maternal morbidity was defined using the CDC’s definition for severe maternal morbidity (SMM). Neonatal morbidity was defined according to the Joint Commission metric, Unexpected Complications in Term Newborns (either moderate or severe). Poisson regression models were used to examine these outcomes with hospital CD rates, using low-risk births as the Poisson exposure and robust standard errors. P-values <0.05 were considered statistically significant. 621 hospitals were included in the analysis. The mean CD rate was 30.5% (SD 7.0%). The median SMM rate was 1.4 (IQR 0.7, 2.2) per 100 deliveries. Excluding transfusion, the most common SMM condition, the median SMM rate was 0.5 (IQR 0.2, 0.7) per 100 deliveries. The median rates of severe and moderate unexpected newborn complications were 1.0 (IQR 0.6, 1.7) and 1.8 (IQR 0.9, 2.9) per 100 low-risk newborns. Figures 1 and 2 show the general linear trends between hospital CD rate and SMM and unexpected newborn complication rates. In the unadjusted model, SMM, with and without transfusion, and moderate neonatal complications were positively associated with hospital CD rates. However, after adjustment for case mix and hospital factors, only the relationship with SMM including transfusion remained significant (IRR 1.033 (95%CI 1.017, 1.049)). There is a 3.3% increase in the incidence of SMM for every percentage point increase in a hospital’s CD rate. This relationship appears to be driven by transfusion. There was no clear association between CD and unexpected newborn complications rates at the individual hospital level. These data can help guide hospitals and policymakers in setting CD rate targets.View Large Image Figure ViewerDownload Hi-res image Download (PPT)