COVID-19 mortality rate elevated in pregnant women
Pregnant women with COVID-19 are more likely to die from the novel coronavirus than nonpregnant individuals similar in age, according to research published in the American Journal of Obstetrics and Gynecology.
“This study represents another strong piece of evidence that pregnant women are more vulnerable to SARS-CoV-2 infections, as well as other highly pathogenic respiratory infections,” Kristina M. Adams Waldorf, MD, FACOG, professor of obstetrics and gynecology at the University of Washington, told Healio Primary Care. “As women represent a large part of the essential workforce, we still have a large group at risk for a more severe course of COVID-19 and death.”
Adams Waldorf and colleagues conducted a statewide multi-center retrospective cohort study in Washington. They identified pregnant women with confirmed SARS-CoV-2 infection based on polymerase chain reaction testing from March 1, 2020, through June 30, 2020, at 35 cities across the state.
A total of 240 pregnant women were included in the study. Among these women, 10% were hospitalized for COVID-19 concerns and 3.3% received care in the ICU.
Among all pregnant women with COVID-19, 56.3% were diagnosed during the third trimester, 27.9% were diagnosed during the second trimester and 15.8% were diagnosed during the first trimester. Most (77.1%) were symptomatic at the time of testing.
Adams Waldorf and colleagues found that 90.8% of women who tested positive had mild disease, 7.5% had severe disease and 1.7% had critical disease.
The researchers determined that, overall, the hospitalization rate for COVID-19 was 3.5-fold higher among pregnant women (10%) compared with nonpregnant adults aged 20 to 39 years (2.8%; RR = 3.5; 95%CI 2.3-5.3) in Washington.
Among hospitalized patients, 40.9% delivered while hospitalized for COVID-19, 79.1% received oxygen support and 16.7% underwent mechanical ventilation.
Three pregnant women with COVID-19 died, yielding a maternal mortality rate of 1,250 out of 100,000 pregnancies (95% CI, 258-3,653). The researchers noted that this COVID-19 mortality rate was 13.6-fold higher than the rate in similarly aged nonpregnant adults in the state, which was 91.7 per 100,000 pregnancies, with an absolute rate difference of 1.2% between the groups (95% CI; -0.26-2.57).
The deaths among pregnant women accounted for 9.4% of COVID-19-related deaths for the age group in Washington, according to the researchers.
Based on the findings, Adams Waldorf said that pregnant women should “absolutely” be prioritized for COVID-19 vaccination.
“Pregnancy is a finite condition and delaying the vaccine would withhold clear benefit from pregnant individuals who face increasing risk with advancing gestational age,” she said.
She added that additional research is needed to further assess the effects of COVID-19 in pregnant women.
“The immune response in pregnancy is altered to protect the fetus from a ‘rejection response’ akin to transplanted organ with a different genetic makeup,” Adams Waldorf said. “Although this shift in immune profile benefits the fetus, it may be at the mother’s expense in fighting a severe respiratory infection like SARS-CoV-2 or influenza virus.”
She also said that more information is needed to determine why pregnant women have increased vulnerability to respiratory infections and how they can be treated.
“These questions need our attention urgently,” she said.