Monitoring childbirth morbidity using hospital discharge data: further development and application of a composite measure.

Objective: The purpose of this study was to evaluate the use of a childbirth composite morbidity indicator for monitoring childbirth morbidity at hospital and regional levels in California.

Study Design: Study data were obtained from the 2005 linked maternal and neonatal discharge dataset for California hospitals. The study population was limited to laboring women with singleton, term (≥37 weeks' gestation), inborn, and live births. Women with and without pregnancy complications were stratified into high- and low-risk groups. The composite outcome was defined as any significant morbidity of the mother or newborn infant during the childbirth admission. Submeasures for maternal and neonatal composite morbidity and for severe maternal morbidity were examined with both aggregate and hospital-level analyses.

Results: Of 377,869 eligible deliveries, 120,218 (31.8%) were categorized as high risk and 257,651 (68.2%) were categorized as low risk. High-risk women had higher morbidity rates for all comparisons. The mean childbirth composite morbidity rate was 21% overall: 28% for high-risk women and 18% for low-risk women. For high- and low-risk strata, the rates of maternal complications were 18% and 13%, and the rates of severe maternal morbidity were 1.4% and 0.5%, respectively. There was substantial variation across hospitals for all measures.

Conclusion: The childbirth composite morbidity rate is designed to report childbirth complication rates that combine maternal and neonatal morbidity. This measure and its submeasures met the criteria for quality indicator evaluation as specified by the Agency for Healthcare Research and Quality and can be used for benchmarking or for monitoring childbirth outcomes at regional levels.