Adolescence is a preriod of important changes, with significant impact on the individual's future. The manifestation of maladaptative behavior like pregnancy (P) and school drop-out (D) have serious consequences, especially in low socioeconomic level (SEL). The prediction and prevention of pregnancy and school failure to predict and eventually prevent them is a topic of growing interest. Variables associated with P and D were studied: family stability, school achievement, self-esteem, religiosity, parent's education and premisiveness, interfamily relation and use of free time. We constructed a questionnaire and administered it to 3000 female students between 12 and 19 years old, of lower to middle SEL. In a two year follow-up we observed P=84 and D=141. We applied a multiple regression analysis using the SAS statistics package. The best variables for constructing the PRPD were: age (0,143), scholastic qualifications (-4,715), level of maternal education (7,966), the responses: “I am not happy with how I look”(10,693), “the father allows her to go out by herself with her boyfriend”(6,98),“the mother does not permit her to go on field trips”(7,428), and“I do not participate in family decisions”(10,014) (intercept = 13,556). The predictor reached a sensitivity of 74,7% and a specificity of 72%. Potencial applications are discussed.