Nigeria, the most populous country in Africa, has one of the world’s highest birth rates for adolescents and the prevalence of sexually transmitted diseases among the country’s female adolescents has spiked rapidly in recent years. This study utilized a cross-sectional school survey of 4,218 students aged 12 to 21 years who were attending 39 schools in Plateau State, Nigeria. Survey questions asked students if they had ever engaged in sexual intercourse and then focused on variables such as sexual history (including incidents of forced sex), age, sex, religion, family polygamy, educational attainment of parents, deceased parents, and sense of connectedness to parents and school. Responses from 2,705 students comprised the final analysis, which revealed that students from polygamous family structures were more likely to have engaged in sexual activity than students from monogamous family structures. Some of the effect of family structure was found to be due to greater incidents of adolescent marriage and forced sex in these family structures. However, students’ sense of connectedness to parents and school, regardless of family structure, decreased the likelihood that the students had engaged in sexual activities. The authors suggest that the findings regarding a sense of connectedness to parents and school as a protective factor against early sexual initiation should be used to devise prevention and intervention programs for the country’s youth. Tables, references