Pregnant Women at High Risk of COVID-19 Mortality

February 8th, 2021

By Gary Evans, Medical Writer

Case-fatality rates in pregnant patients infected with SARS-CoV-2 were a stunning 13.6 times higher than similarly aged non-pregnant women with COVID-19, according to a pre-print study in Washington state.

Researchers followed 240 pregnant women between March 1 and June 30, 2020, in a multicenter, retrospective cohort study from 35 sites in Washington. Three patients died and 24 patients were hospitalized for COVID-19. The findings suggest COVID-19 pregnancy mortality rates are seriously undercounted nationally in the absence of active surveillance for such cases, the authors emphasized.

“Notably, in mid-October of 2020, the CDC [Centers for Disease Control and Prevention] reported only 45 maternal deaths in pregnant women with confirmed SARS-CoV-2 infections across the U.S.,” the authors reported. “If complete, this would mean that the three cases in our study population represented 7% of the total maternal deaths in pregnant women with SARS-CoV-2 across the U.S. despite annual births among our study sites making up an estimated 1.4% of the total nationwide. This is most likely due to underreporting and not a higher death rate in Washington state.”

Hospitalized pregnant patients were more likely to have a comorbidity or underlying conditions, including asthma, hypertension, type 2 diabetes, autoimmune disease, and obesity. The three women who died of COVID-19 in Washington state were from minority ethnic groups who have shown to be at greater risk of the virus. That said, most of the pregnant patients with COVID-19 had asymptomatic or mild COVID-19 disease and healthy pregnancies.

Hospital Infection Control & Prevention (HIC) sought further comment on the study from lead author Kristina Adams-Waldorf, MD, professor of obstetrics and gynecology at the University of Washington in Seattle. This interview was edited for length and clarity.

HIC: The high mortality rate is the most disturbing finding. Can you discuss your reaction to this and the implications for preventing these COVID-19 deaths?

Adams-Waldorf: Deaths in pregnant women are relatively rare, and we work incredibly hard to prevent them. So, the three deaths that we found by tracking women for the first few months of the pandemic were shocking to us and a sky-high maternal mortality rate compared to what we are used to from historical levels of maternal mortality in Washington state. When we compared them to the general population at a similar age [with COVID-19], it was 13.6 higher mortality rate, which was also saddening. It’s not completely a surprise because pregnant women are highly susceptible to influenza, and pregnant women die every year from flu viral infection, which is why we try so hard to vaccinate all pregnant women in the U.S. but succeed only about half the time in doing so.

HIC: The study suggests there is severe underreporting of mortality related to COVID-19 in pregnancy in the United States. Compared to CDC data, your study had 7% of the total maternal deaths in pregnant women with SARS-CoV-2 nationally, with only of 1.4% of the total births.

Adams-Waldorf: Yes, the second shock was when we compared our numbers of maternal deaths to what the CDC was reporting as the total number of maternal deaths. It was at that moment that we realized how undercounted the deaths of pregnant women are nationally. What the CDC has are these COVID-19 case reports filled out by the states. There is a check box [to mark whether] they are pregnant or not. Most of the time those are not filled out, so they can’t know for certain whether a person with COVID or a person who died was pregnant. As you can imagine, the public health departments have been completely overwhelmed during this [pandemic]. So, having a lot of time to track down information on different people when they are getting thousands of these per day is not really a priority. They are missing this in about 65% of all their case reports. They end up with skewed data or a lot of missing data.

HIC: As of January 7, the CDC states “getting vaccinated is a personal choice for people who are pregnant.” Based on your findings it appears the risk of a potential bad outcome of COVID-19 infection during pregnancy outweighs the vaccine risk.

Adams-Waldorf: Yes, absolutely. In my opinion the risk of a bad outcome from COVID-19 and pregnancy is high. Our death rate was 1 in 80. Our hospitalization rate was 1 in 10, and we had women that had months of long-haul COVID-19 symptoms. The toll that it took on them in addition to their pregnancy was significant. I am a strong advocate of COVID-19 vaccine. I think that there is this myth that pregnant women can just sit at home and protect themselves from the pandemic and telework. That is not really reality. Pregnant women are on the front lines as healthcare workers and in essential jobs like teachers. They have large families sometimes and they are exposed to other people.

For more from this interview, please see the March issue of Hospital Infection Control & Prevention.