Prevalence and temporal trend of prematurity in Brazil before and during the Covid-19 pandemic: analysis of the temporal series from 2011 to 2021

Abstract

Objective: To measure prematurity prevalence from 2011-2021, according to brazilian’s macroregion and maternal characteristics, in the last 11 years, comparing the pandemic years of COVID-19 (2020-2021), with the historical series (2011-2019). Methods: Ecological study based on the Information System on Live Births. Prevalences are calculated according to year, macro-region, and maternal characteristics. Time series analysis by the generalized linear model of Prais-Winsten. Results: Prematurity rate between 2011-2021: 11,1%, stable in the period. The mean in the pandemic period (11.3% 95%CI 11.2;11.4%) resembled the baseline mean (11.0%95%CI10.6; 11.5). The northern region (11.6%) had the highest rate in 2011-2021. Twin pregnancy (56.3%) and pregnant with 4-6 prenatal visits (16.7%) presented an increasing trend (p<0.001).  Extreme maternal age, black and indigenous women, and lower education had higher rates. Conclusion: Greater prematurity in pregnant in women in social vulnerability, twin pregnancies, and Northern Region. The rates remained stable, with no difference between periods.