A total of 1308 women (445 from KP-WC and 863 from SFGH) met the inclusion criteria and were included in the analysis. At SFGH in 2005, the rate of cesarean delivery was 24.5% overall and 22.6% among study participants (P=.3); at KP-WC, the overall rate in 2005 was 26.4% and the rate among study participants was 30.1% (P=.1).