OBJECTIVE

To evaluate the effect of statewide efforts to reduce nulliparous, term, singleton, vertex (NTSV) cesarean delivery rates in California.

METHODS

This was a population-based study of all NTSV births in California from 2015 to 2019. In 2015, all California hospitals with NTSV cesarean delivery rates above the 23.9% Healthy People 2020 target were invited to join a CMQCC (California Maternal Quality Care Collaborative)-sponsored, 3-year, multifaceted collaborative or a system-level quality collaborative to safely support vaginal birth. We examined the cesarean delivery rate overall and by participation or nonparticipation in a collaborative program. Secondarily, for hospitals that started with an NTSV cesarean delivery rate above 23.9%, we compared patient-level, hospital-level, and obstetric management characteristics between hospitals that met the Healthy People 2020 target (cesarean delivery rate below 23.9%) in 2019 and those that did not.

RESULTS

There were 758,268 NTSV births at 238 hospitals. Annual mean NTSV cesarean delivery rates decreased among all racial and ethnic groups statewide and among all patients, regardless of payer, maternal age, or body mass index (BMI). The decrease in cesarean delivery was driven largely by a decrease in the frequency of cesarean delivery performed for labor dystocia (14.9% in 2015 to 12.8% in 2019) and from cesarean delivery before the onset of labor (4.2% in 2015 to 3.3% in 2019). For hospitals that started with an NTSV cesarean delivery rate above 23.9%, NTSV cesarean delivery rates among 80 hospitals participating in the CMQCC had a mean±SD decline of 6.9±5.9%, 13 hospitals participating in the system-level collaborative had a 5.0±4.5% decline, and those not participating in any collaborative had a 2.1±6.0% decline. In multivariable analysis, there was no association between meeting the Healthy People target and any of the hospital-level factors or aggregated patient-level characteristics. Rates of induction of labor increased in both groups and were not associated with a change in cesarean delivery rates.

CONCLUSION

Hospitals in California between 2015 and 2019 with a wide variation in institutional and patient characteristics successfully reduced their NTSV cesarean delivery rates. Reduction in the NTSV cesarean delivery rate at hospitals that started above the Healthy People target was not associated with differences in patient characteristics but rather a reduction in cesarean deliveries for labor dystocia and cesarean deliveries performed before the onset of labor.