Declining cesarean delivery rates in California: An effect of managed care?, ,

OBJECTIVES: We hypothesized that movement from traditional indemnity insurance to managed care in California between 1983 and 1994 would lead to reductions in the rate of cesarean delivery. STUDY DESIGN: We decomposed the frequency of cesarean delivery with each primary diagnosis into the product of the diagnosis rate among all women and the cesarean delivery rate among women with the given diagnosis (conditional cesarean delivery rate). We used logistic regression to estimate the diagnosis and conditional cesarean delivery rates. RESULTS: Adjusted and observed cesarean delivery rates are indistinguishable. Both the diagnosis rates and the conditional cesarean delivery rates contributed to the increase in the cesarean delivery rate between 1983 and 1987. The subsequent decline is attributable to the decline in the repeated cesarean delivery rate. CONCLUSIONS: The increase in managed care in California played no apparent role in the decline in the cesarean delivery rate. With the exception of Kaiser health maintenance organizations, managed care providers and indemnity insurers managed deliveries similarly. (Am J Obstet Gynecol 1998;179:657-64.)