This study analyzed the factors associated with first sexual intercourse among 427 mothers with 14-16 years of age from Porto Alegre (RS), Brazil. Data on adolescent socio-demographic status (skin color, religion and schooling gap) and reproductive aspects (age at menarche, age at first sexual intercourse, partnership in first sexual intercourse and partner's age) were collected through household survey. Data analysis was performed using bivariate and multivariate analysis through Poisson regression with robust variance. Among adolescents with early first sexual intercourse (up to 14 years), 77.4% had menarche at up to 12 years of age and 16.4% had casual partners in the first sexual intercourse. These variables were associated with the outcome and showed that early menarche (OR=1.26; CI 95%:1.04-1.52) and casual partner at first sexual intercourse (OR=1.28; CI 95%:1.09-1.49) increase by respectively 26% and 28% the prevalence of early first sexual intercourse. This study highlights the need to strengthen health programs and policies already implemented, such as the School Health Program, as well as reinforces that parents and teachers need to be oriented in an integrated manner in order to facilitate dialogue with adolescents and provide adequate counseling.
Sexuality; Sexual behavior; Adolescent