[Risk factors and predictors of induced abortion: a population-based study]

This study aimed to identify key risk factors and predictors of induced abortion. A cross-sectional population-based study was conducted with a representative sample of 3,002 women 15 to 49 years of age in southern Brazil, randomly assigned to answer questions on induced abortion using either the ballot-box method or the indirect questioning method. Socioeconomic, demographic, and reproductive data were obtained through a pre-coded questionnaire. Data analysis used epidemiological statistical inferences and Bayes' theorem to calculate a posteriori probability. Induced abortion was strongly associated with fetal loss for all age groups. In adolescents, the main predictors were low socioeconomic level, low schooling, elevated school drop-out, and knowledge of a large number of contraceptive methods. For all other women, socioeconomic characteristics and skin color were not associated with abortion. For women aged 20 to 49 years, marital status and reproductive characteristics, including knowledge of contraceptive methods, were the most frequent risk factors and predictors of induced abortion.