ABSTRACT: BACKGROUND:Cesarean section (CS) rate has risen dramatically and stayed at a very high level in China over the past two to three decades. Given the short- and long-term adverse effects of CS, effective strategies are needed to reduce unnecessary CS. We aimed to evaluate whether a multifaceted intervention would decrease the CS rate in China. METHODS:We carried out a cluster-randomized field trial with a multifaceted intervention in Shanghai, China, from 2015 to 2017. A total of 20 hospitals were randomly allocated into an intervention or a control group. The intervention consisted of more targeted health education to pregnant women, improved hospital CS policy, and training of midwives/doulas for 8 months. The study included a baseline survey, the intervention, and an evaluation survey. The primary outcome was the changes of overall CS rate from the pre-intervention to the post-intervention period. A subgroup analysis stratified by the Robson classification was also conducted to examine the CS change among women with various obstetric characteristics. RESULTS:A total of 10,752 deliveries were randomly selected from the pre-intervention period and 10,521 from the post-intervention period. The baseline CS rates were 42.5% and 41.5% in the intervention and control groups, respectively, while the post-intervention CS rates were 43.4% and 42.4%, respectively. Compared with the control group, the intervention did not significantly reduce the CS rate (adjusted OR?=?0.92; 95% CI 0.73, 1.15). Similar results were obtained in subgroup analyses stratified by the risk level of pregnancy, maternal age, number of previous CS, or parity. Scarred uterus and maternal request remained the primary reasons for CS after the interventions in both groups. The intervention did not alter the perinatal outcomes (adjusted change of risk score?=?-?0.06; 95%CI -?0.43, 0.31). CONCLUSIONS:A multifaceted intervention including more targeted prenatal health education, improved hospital CS policy, and training of midwives/doulas, did not significantly reduce the CS rate in Shanghai, China. However, our experience in implementing a multifaceted intervention may provide useful information to other similar areas with high CS use. TRIAL REGISTRATION:This trial was registered at the Chinese Clinical Trial Registry (www.chictr.org.cn) (ChiCTR-IOR-16009041) on 17 August 2016.