This article works for a better knowledge of the determinants and consequences early pregnancies of adolescent girls in schools in Togo. So, this article aims to analyze the determinants and consequences of early pregnancies among adolescents in schools. This study, being qualitative, was based on data collection tools such as the interview guide, the observation grid with 1,500 respondents identified by the random sampling technique and by reasoned choice. Following this research, the results thus obtained show that the occurrence of early pregnancies among teenage girls in schools is caused by the irresponsibility of parents, the lack or ineffectiveness of discussions between children and parents on sexuality, bad company , early marriages, economic precariousness, and sexuality linked to culture, which ultimately promotes girls dropping out of school, death following attempted abortions, changes in social relationships, rejection, etc.