Aim: To identify the profile of precocious (under 16 years of age) and late pregnant adolescents (17-19 years) by comparing neonatal results. Method: This is a unique cohort in which potential confounders of a biological and socio-demographic nature were identified (p < 0.05), with subsequent analysis of adverse neonatal results in both studied groups, using the chi-square test. Results: We identified differences in the workplace, first pregnancy, income, labor in the Unified Health System, and cohabitation with a partner. Low Apgar scores and respiratory disorders were more frequent in early adolescents. The need for resuscitation and admission to an intensive care unit did not differ between groups. Discussion: The studied adolescents revealed that they live in social risk. A relationship was found between Apgar scores and respiratory disorders in the fetuses of early adolescents. Conclusion: We suggest the need for investment to prevent pregnancy in this age group, and for prenatal care and skilled birth support, especially for precocious adolescents.