Maternal and perinatal health indicators in Brazil over a decade: assessing the impact of the COVID-19 pandemic and SARS-CoV-2 vaccination through interrupted time series analysis.

Background: Few studies have evaluated the effects of the Coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 virus, on maternal and perinatal health at a populational level. We investigated maternal and perinatal health indicators in Brazil, focusing on the effects of the COVID-19 pandemic, and SARS-CoV-2 vaccination campaign for pregnant women. Methods: Utilizing interrupted time series analysis (January 2013-December 2022), we examined Maternal Mortality Ratio, Perinatal Mortality Rate, Preterm Birth Rate, Cesarean Section Rate, and other five indicators. Interruptions occurred at the pandemic's onset (March 2020) and pregnant women's vaccination (July 2021). Results were expressed as percent changes on time series' level and slope. Findings: The COVID-19 onset led to immediate spikes in Maternal Mortality Ratio (33.37%) and Perinatal Mortality Rate (3.20%) (p < 0.05). From March 2020 to December 2022, Cesarean Section and Preterm Birth Rates exhibited upward trends, growing monthly at 0.13% and 0.23%, respectively (p < 0.05). Post start of SARS-CoV-2 vaccination (July 2021), Maternal Mortality Ratio (-34.10%) and Cesarean Section Rate (-1.87%) promptly declined (p < 0.05). Subsequently, we observed a monthly decrease of Maternal Mortality Ratio (-9.43%) and increase of Cesarean Section Rate (0.25%) (p < 0.05), while Perinatal Mortality Rate and Preterm Birth Rate showed a stationary pattern. Interpretation: The pandemic worsened all analyzed health indicators. Despite improvements in Maternal Mortality Ratio, following the SARS-CoV-2 vaccination campaign for pregnant women, the other indicators continued to sustain altered patterns from the pre-pandemic period. Funding: No funding.