Comorbidities, poverty and social vulnerability as risk factors for mortality in pregnant women with confirmed SARS-CoV-2 infection: analysis of 13 062 positive pregnancies including 176 maternal deaths in Mexico

Abstract

ABSTRACT Background

Mortality due to COVID-19 in pregnancy in developing countries is critical. The identification of clinical and socio-demographic risk factors related to mortality in pregnant individuals could guide public policies to prioritize vulnerable individuals for vaccination. We aimed to evaluate the association between comorbidities and social determinants to mortality and severe COVID-19 disease in pregnant individuals.

Methods

This is an ongoing nationwide prospective cohort study, that includes all pregnant women with positive RT-qPCR from the Mexican National Registry of Coronavirus. The primary outcome was death by COVID-19. Secondary outcomes were pneumonia, intubation, and intensive care unit (ICU) admission. The association between comorbidities and socio-demographic characteristics with each adverse outcome was explored by a log-binomial regression model adjusted by possible confounders.

Results

There were 176 (1.35%) maternal deaths among 13,062 consecutive SARS-CoV-2 positive pregnant individuals. Age as a continuous (aRR [adjusted relative risk]: 1.08; 1.05-1.10) or categorical variable was associated with maternal death. Pregnant individuals of 35- 39 years (RR: 3.16; 2.34-4.26) and 40 years and older (RR: 4.07; 2.65-6.25) had higher risk for mortality. Other risk factors associated with maternal mortality were pre-existing diabetes (aRR: 2.66; 1.65-4.27), chronic hypertension (aRR: 1.75; 1.02-3.00), and obesity (aRR: 2.15; 1.46-3.17). Very high social vulnerability had higher risk of mortality (aRR: 1.89; 1.27-2.84), while very low social vulnerability had a lower risk of death (aRR: 0.48; 0.31-0.74). Being poor and extremely poor were also risk factors for maternal mortality (aRR: 1.53; 1.09-2.15, and aRR: 1.83; 1.32-2.53, respectively).

Conclusions

Our study, which is the largest prospective consecutive cohort to date, has confirmed that advanced maternal age, diabetes, hypertension, obesity, very high social vulnerability, and low socioeconomic status are risk factors of COVID-19-related mortality