Is pregnancy a risk factor for in‐hospital mortality in reproductive‐aged women with SARS‐CoV‐2 infection? A nationwide retrospective observational cohort study

Abstract

Objective To examine the effect of pregnancy on coronavirus disease 2019 (COVID‐19) ‐related in‐hospital mortality in women of reproductive age (between 15 and 45 years), with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection confirmed with polymerase chain reaction tests, adjusted for factors such as co‐infection and intervention that were not considered in existing literature. Methods Data gathered from a nationwide database in Brazil were analyzed using multivariate logistic regression and multivariate Cox regression. Adjusted odds ratios and hazard ratios of independent factors associated with in‐hospital death were calculated. Results A total of 97 712 women were included in the study. After the adjustment for sociodemographic factors, epidemiologic characteristics, pre‐existing medical conditions, and intervention, pregnant women were found to be associated with lower risk for in‐hospital mortality as well as longer survival time compared with non‐pregnant women. When covariates of intervention were omitted from the analysis, pregnancy did not appear to be a significant factor associated with mortality. Conclusion With the adjustment for intervention that was shown to be an independent factor associated with mortality, pregnancy appeared to have a favorable effect on SARS‐CoV‐2 infection. Given the immunosuppressed state of pregnancy, this finding is in line with the hypothetical protective role of a weaker immune response that inhibits the production of proinflammatory cytokine.

Are in‐hospital COVID‐19‐related mortality and morbidity in pregnancy associated with gestational age?

“…This was a cohort study of pregnant women with confirmed SARS‐CoV‐2 infection who were hospitalized in Brazil from the index case on 25 February 2020 to 29 November 2021. Data were obtained from SIVEP‐Gripe (Sistema de Informação de Vigilância Epidemiológica da Gripe), a Brazilian nationwide database, that has been described in more detail elsewhere 18 , 21 . Developed by the Federal Government of Brazil during the influenza pandemic in 2009, SIVEP‐Gripe aims to strengthen surveillance of severe acute respiratory syndrome‐related viral infection.…”

“…For deceased patients, the time from admission to recovery was recorded as ‘NA’ and omitted from the relevant analysis. If data were missing regarding signs, symptoms, history of exposure to animals, nosocomial infection or comorbidities, we assumed that characteristic to be absent 18 . Data on abnormal chest X‐ray were missing if imaging was not performed or registered.…”

“…However, the findings remain contradictory. Some studies have found a higher rate of mortality 7–9 and a more severe outcome 9,10 in pregnant women compared with non‐pregnant women, whereas other studies found similar clinical characteristics or severity between the two populations 11–14 or even milder symptoms and lower mortality in pregnant women 15–18 .…”

Better healthcare can reduce the risk of COVID-19 in-hospital post-partum maternal death: evidence from Brazil

“…The database has been the primary source of information on COVID-19-related hospital admission and deaths in Brazil, and has been described elsewhere. 7 …”

“…For any missing data on signs, symptoms (except for abnormal chest X-ray) or co-morbidities, the clinical condition was assumed to be absent, following the approach in previous studies with the same database. 7 , 17 Missing data of abnormal chest X-ray were excluded from the relevant analysis because imaging was not performed. Cases with ethnicity missing were also excluded from the corresponding analysis.…”