This paper assesses the prevalence of induced abortion among prostitutes and lists the most frequent abortion practices. A survey was conducted with 310 prostitutes between 18 and 39 years old, by sampling age quotas in the five territorial areas of Teresina, in the state of Piauí, Brazil. Data collection was conducted using two questionnaires: the first, by the ballot-box technique, with questions about abortion; the second, completed by the researcher, with socio-demographic information. The practice of abortion was reported by 163 women (52.6%). Most prostitutes performed 1 abortion (50.3%), but 16.5% of them reported 3 or more. Misoprostol was used alone in 68.1% of the reports and associated with tea and/or probes in 9.2%, followed by tea in 13.4%, probes in 3.7%, and uterine curettage in unregulated clinics in 3.7%. There was post-abortion hospitalization in 47.8% of the cases. After adjustment of the multiple logistic regression model, the variable that remained significantly associated with abortion was to have had 3 or more pregnancies. These results revealed that induced abortion is an event of great prevalence among prostitutes in Teresina. Misoprostol is the most common method to abort and hospitalization was necessary in almost half of the cases.