This paper estimates whether physicians anticipate to public disclosure of their delivery performance by altering C–section rates. Exploring a public consultation period of a legislation requiring private hospitals to disclose delivery rates to patients in Brazil, the estimates indicate that at least 0.8 percentage point reduction in C–section rates reflects physicians anticipation response. This result concentrates on low–risk gestations, scheduled procedures and becomes stronger with market competition. No effect was detected for emergency C–sections, or on the supply of physicians, obstetric nurses and hospital facilities. Regressions using market share, patients’ characteristics, and birth presentation suggest that patients did not anticipate information disclosure by moving to other hospital or using alternative sources of information.