Pregnant women with SARS-CoV-2 infection are at higher risk of death and severe pneumonia: propensity score-matched analysis of a nationwide prospective cohort study (COV19Mx).

Background Limited, unmatched data reported low complication rates in pregnant women with COVID-19. This study compared COVID-19-related outcomes in pregnant women versus non-pregnant women after adjusting for potential risk factors for severe outcomes. Methods Data were obtained from the COVID-19 National Data Registry of Mexico, which is an ongoing prospective cohort of people of any age with clinically suspected SARS-CoV-2 infection and admitted to 475 monitoring hospitals. This study included pregnant and non-pregnant women of reproductive age (15-49 y) with COVID-19 confirmed by reverse transcription polymerase chain reaction. To adjust for underlying risk factors, propensity score matching was conducted for chronic obstructive pulmonary disease, asthma, smoking, hypertension, cardiovascular disease, obesity, diabetes, and age. The primary outcome was death. Secondary outcomes were pneumonia, intubation, and intensive care unit (ICU) admission. Results The initial sample comprised of 5183 pregnant and 175,908 non-pregnant COVID-19 patients. The crude (unmatched) rates of death, pneumonia, intubation, and ICU admission in pregnant and non-pregnant women were 1.5% vs. 1.5%, 9.9% vs. 6.5%, 8.1% vs. 9.9%, 13.0% vs. 6.9%, respectively. After propensity score matching (5183 pregnant- and 5183 non-pregnant matched women), pregnant women had higher odds of death (odds ratio [OR] 1·65, 95% CI 1·30-2.09), pneumonia (OR 1·99, 95% CI 1·81-2·19) and ICU admission (OR 2.25, 95% CI 1·86-2·71) than non-pregnant women, but similar odds of intubation (OR 0·93, 95% CI 0·70-1·25). Conclusions After adjusting for background demographic and medical factors, pregnancy is a risk factor for death, intubation and ICU admission in SARS-CoV-2-infected women of reproductive age. This article is protected by copyright. All rights reserved.