Disease Severity, Pregnancy Outcomes and Maternal Deaths among Pregnant Patients with SARS-CoV-2 Infection in Washington State.

Document Type


Publication Date


Publication Title

American journal of obstetrics and gynecology




BACKGROUND: Evidence is accumulating that coronavirus disease 2019 (COVID-19) increases the risk for hospitalization and mechanical ventilation in pregnant patients and for preterm delivery. However, the impact on maternal mortality and whether morbidity is differentially affected by disease severity at delivery and trimester of infection is unknown.

OBJECTIVES: To describe disease severity and outcomes of SARS-CoV-2 infections in pregnancy across Washington State including pregnancy complications and outcomes, hospitalization, and case fatality.

STUDY DESIGN: Pregnant patients with a polymerase chain reaction confirmed SARS-CoV-2 infection between March 1 and June 30, 2020 were identified in a multi-center retrospective cohort study from 35 sites in Washington State. Sites captured 61% of annual state deliveries. Case fatality rates in pregnancy were compared to COVID-19 fatality rates in similarly aged adults in Washington State using rate ratios and rate differences. Maternal and neonatal outcomes were compared by trimester of infection and disease severity at the time of delivery.

RESULTS: The principal study findings were: 1) among 240 pregnant patients in Washington State with SARS-CoV-2 infections, 1 in 11 developed severe or critical disease, 1 in 10 were hospitalized for COVID-19, and 1 in 80 died; 2) the COVID-19-associated hospitalization rate was 3.5-fold higher than in similarly-aged adults in Washington State [10.0% vs. 2.8%; rate ratio (RR) 3.5, 95% confidence interval (CI) 2.3-5.3]; 3) pregnant patients hospitalized for a respiratory concern were more likely to have a comorbidity or underlying conditions including asthma, hypertension, type 2 diabetes, autoimmune disease, and Class III obesity; 4) three maternal deaths (1.3%) were attributed to COVID-19 for a maternal mortality rate of 1,250/100,000 pregnancies (95%CI 257-3,653); 5) the COVID-19 case fatality in pregnancy was a significant 13.6-fold (95%CI 2.7-43.6) higher in pregnant patients compared to similarly aged individuals in Washington State with an absolute difference in mortality rate of 1.2% (95%CI -0.3-2.6); and 6) preterm birth was significantly higher among women with severe/critical COVID-19 at delivery than for women who had recovered from COVID-19 (45.4% severe/critical COVID-19 vs. 5.2% mild COVID-19, p<0.001).

CONCLUSIONS: COVID-19 hospitalization and case fatality rates in pregnant patients were significantly higher compared to similarly aged adults in Washington State. This data indicates that pregnant patients are at risk for severe or critical disease and mortality compared to non-pregnant adults, as well as preterm birth.

Clinical Institute

Women & Children


Infectious Diseases


Obstetrics & Gynecology