Sexual initiation and contraceptive use among adolescent women in northeast Brazil.

To estimate trends and determinants of sexual initiation and contraceptive use among adolescent women in Northeast Brazil, multivariate logistic hazard models are used that draw on data from three Demographic and Health Surveys conducted there between 1986 and 1996. Educational attainment is among the variables found to be associated most consistently with differential risk of engaging in first intercourse during adolescence, including premarital intercourse, and of contraceptive use during sexual initiation. Greater frequency of attending religious services and greater exposure to television are also associated with lower rates of sexual initiation and higher use of contraceptives. Seemingly diminishing returns of education on delayed sexual activity may help explain, in part, observed increases in the absolute level of adolescent sexual experience across survey periods, however. Multilevel modeling techniques pointing to the existence of cluster-level random variances underline the need for further research into community influences on individual sexual activity.