A population‐based study of the relationship between advanced maternal age and premature/early‐term birth in Brazil

Abstract

Objective To verify whether advanced maternal age (AMA), defined as women of ≥35 years, is associated with premature and early‐term birth in Brazil, according to the onset of labor (spontaneous or provider‐initiated). Methods Cross‐sectional population‐based study. The “Birth in Brazil” study interviewed 23 894 puerperal women between 2011 and 2012, in all regions of Brazil. The current analysis included 17 994 adult mothers and their newborns (15 448 aged between 20–34 years, and 2536 ≥ 35 years). A propensity score was used to assess the likelihood of AMA women giving birth to premature or early‐term infants (spontaneous or provider‐initiated) compared to women aged 20–34 years. To balance the groups, we used maternal, prenatal, and childbirth characteristics. Results The general prematurity rate was 10.24%, of which the majority of births were spontaneous (55.73%). Conversely, early‐term births were more often provider‐initiated (54.81%). AMA did not increase the chance of premature births, whether spontaneous or provider‐initiated. However, AMA was associated with a higher rate of provider‐initiated early‐term birth (OR = 1.48; 95% CI: 1.23–1.77). Conclusion AMA alone does not contribute to premature birth; AMA’s independent association with provider‐initiated early‐term birth may not be based solely on clinical indications.

Retrospective Study of the Metrorrhagia of the First Trimester. Follow-up and Gestational Complications

“…According to data from the National Institute of Statistics, the prematurity rate represents 6.5-9% of all births, and may increase to and reach 12.5% in reference centers. We compared the prematurity rate obtained in our study with that published by other work groups and found similar results, with a rate of pre-term birth around 10.24% [13,14].…”

Retrospective Study of First Trimester Metrorrhagia: Pregnancy Follow-Up and Relationship with the Appearance of Gestational Complications

“…According to data from the National Institute of Statistics, the prematurity rate represents 6.5-9% of all births and may increase to and reach 12.5% in reference centers. We compared the prematurity rate obtained in our study with that published by other work groups and found similar results, with a rate of pre-term birth around 10.24% [36,37].…”

“…A recent study shows the same conclusions; it assessed the association between maternal age and prematurity and found no increase in maternal age among pregnancies that terminated spontaneously, while they demonstrated a rise in prematurity with increased maternal age among pregnancies that required a planned delivery due to associated medical complications. Therefore, there was a correlation between increased maternal age and prematurity but as a result of maternal medical conditions that required planned delivery [ 36 ].…”