Objective: This study aimed to assess live birth frequency and age-specific fertility rates (ASFR) in the period 1996-2018 and the number of pregnancies at <14 years old in the period 2012-2018.
Methods: This was a cross-sectional study conducted by search on Live Births Data System (SINASC/DATASUS) database.
Results: There was a variation in ASFR in Brazil of 0.78‰ in 1996 to 0.87‰ in 2018 (+11.5%). In the north region, it increased from 1.28‰ to 1.66‰ in 2018. In the northeast region, it increased from 0.72‰ to 1.66‰ (+131%) in 1996-2011, but decreased to 1.31‰ in 2018 (-21% in relation to 2011). When comparing 1996 and 2018, in the southeast region, there was a 22% decrease; in the south region, it was 48.2%; and in the Center-West region, it was 34%; but in the north region, there was a 29.7% increase, and in the northeast region, it was 81.9%. When adding girls who became pregnant aged 13 years and gave birth at 14, there was a threefold increase in the rate.
Conclusions: The increase of pregnancies in <14 years old in less developed regions of Brazil shows an association with socioeconomic factors and reveals the severe problem of rape of vulnerable persons in the country.