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Late pregnancy: impact on prematurity and newborn's weight
Lia Keiko Sousa Shimamura1,2, Denise Leite Maia Monteiro1,3, Célia Regina da Silva1
1Universidade do Estado do Rio de Janeiro - Rio de Janeiro (RJ), Brazil.
Objective:
This study aimed to evaluate the frequency of late pregnancies in Brazil, the age-specific fertility rate (ASFR) in the regions, the rate of prematurity, and the rate of low birth weight (LBW) and their association with advanced maternal age compared with 20-34-year-old women.
Methods:
This was a cross-sectional study conducted by searching the Information System on Live Births (Sistema de Informações Sobre Nascidos Vivos [SINASC]). Data from 1995 to 2018 were collected, and pregnant women were divided into three categories based on their age range: 35-39, 40-44, and ≥45 years. The study calculated the frequency of deliveries of mothers of advanced age in Brazil, the ASFR, and the rates of prematurity and LBW in each group.
Conclusions:
The frequency of deliveries and ASFR ≥35 years increased between 1995 and 2018. The chances of prematurity and LBW were higher with increased maternal age.
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