Association between institutional factors, birth care profile, and cesarean section rates in Santa Catarina.

Objectives: To investigate how institutional factors, represented by the social profile of childbirth care, can relate to cesarean section rates. Methods: A cross-sectional study based on data from Sistema de Informações sobre Nascidos Vivos (SINASC) for the state of Santa Catarina collected information for each of the six municipalities with the largest number of births from the six macroregional areas. For those municipalities, all of the establishments that had obstetric facilities were considered. A total of 61.278 births took place over 61 selected maternity services. Cesarean prevalence ratios (PR), both crude and adjusted for confounders, were estimated for each one of the individual variables using robust Cox regression. Results: Cesarean births were almost as twice as high in private maternity facilities (89%) when compared to the public ones (45.1%). Giving birth in private hospitals increased by at least 50% the prevalence of caesarean section among primiparae (PR = 1.64), Caucasian (PR = 1.57), women with greater attendance to prenatal care (PR = 1.54), and women having daylight birth (PR = 1.5), when compared with those delivering inside the public sector. Conclusion: Differences in cesarean rates in favor of the private system, among women with better social conditions, amongst which it would be expected a lower obstetric risk, have pointed toward differences in obstetric/medical culture permeability and flexibility on medical judgment concerning clinical criteria for cesarean sections.