Pregnant women may be at greater risk of severe Covid-19 illness but aren't more likely to die: CDC
The study of 8,207 pregnant women highlights the importance of pregnant patients being prioritized for a coronavirus vaccine once it becomes available
Pregnant women might be at increased risk for severe Covid-19 illness compared to women who are not expecting, said a research team from the US Centers for Disease Control and Prevention (CDC). According to health experts, pregnant women who get infected with the new coronavirus are more likely to be hospitalized, admitted to an intensive care unit and put on a ventilator.
After adjusting for age, presence of underlying medical conditions and race/ethnicity, researchers found that pregnant women were 5.4 times more likely to be hospitalized, 1.5 times as likely to be admitted to intensive care units and 1.7 times as likely to require mechanical ventilation, the report said. There was no higher risk of death among pregnant women.
Limited information was available so far on the impact of Covid-19 on pregnant women. This is the first time that the CDC has issued such a warning based on a study of more than 8,000 pregnant women in the US. The same report, however, shows that pregnant women are not at higher risk of dying from Covid-19.
During January 22-June 7, 1,573,211 laboratory-confirmed cases of SARS-CoV-2 (the virus that causes Covid-19) infection were reported to CDC as part of national Covid-19 surveillance. Data were available for 91,412 women and of these, 8,207 were pregnant. Among women with Covid-19, approximately one third or 31.5% of pregnant women were reported to have been hospitalized compared with 5.8% of nonpregnant women. The analysis shows that pregnant women were 50% more likely to be admitted to the intensive care unit and 70% more likely to receive mechanical ventilation.
"Pregnant women were admitted more frequently to the ICU (1.5%) than were nonpregnant women (0.9%). Similarly, 0.5% of pregnant women required mechanical ventilation compared with 0.3% of nonpregnant women. Sixteen deaths (0.2%) were reported among 8,207 pregnant women and 208 (0.2%) were reported among 83,205 nonpregnant women," says the team in their analysis. They add, "These findings suggest that among women of reproductive age with Covid-19, pregnant women are more likely to be hospitalized and at increased risk for ICU admission and receipt of mechanical ventilation compared with nonpregnant women, but their risk for death is similar."
The team recommends that to reduce the occurrence of severe illness from Covid-19, pregnant women should be made aware and counseled about the potential risk for severe coronavirus illness. The agency has also expanded list of people at risk of severe illness from Covid-19, which now includes pregnant women. "Prevention of Covid-19 should be emphasized for pregnant women and potential barriers to adherence to these measures need to be addressed," they emphasize. The experts suggest that pregnant women and their families should take measures to ensure their health and prevent the spread of Covid-19. Specific actions pregnant women can take include not skipping prenatal care appointments, limiting interactions with other people as much as possible, taking precautions to prevent getting Covid-19 when interacting with others, having at least a 30-day supply of medicines, and talking to their health care provider about how to stay healthy during the Covid-19 pandemic, they explain.
The analysis shows that 54.4% of pregnant women and 38.2% of nonpregnant women were aged 25-34 years, 22.1% of pregnant women and 38.3% of nonpregnant women were aged 35-44 years. Information on race/ethnicity was available for 80.4% of pregnant women and 70.6% of nonpregnant women. Among pregnant women, 46.2% were Hispanic, 23% were white, 22.1% were black and 3.8% were non-Hispanic Asian compared with 38.1%, 29.4%, 25.4% and 3.2% respectively among nonpregnant women. These proportions differ from those among women with reported race/ethnicity who gave birth in 2019: 24% were Hispanic, 15% were black and 51% were white. While data on race/ethnicity were missing for 20% of pregnant women in this study, these findings suggest that pregnant women who are Hispanic and black might be disproportionately affected by Covid-19 infection during pregnancy, says the study.
Data were available on the presence and absence of underlying chronic conditions for 22.9% of pregnant women and 35% of nonpregnant women. Chronic lung disease (21.8% pregnant; 10.3% nonpregnant), diabetes mellitus (15.3% pregnant; 6.4% nonpregnant), and cardiovascular disease (14.0% pregnant; 7.1% nonpregnant) were the most commonly reported chronic conditions. "Data were not available to distinguish whether chronic conditions were present before or associated with pregnancy, such as gestational diabetes or hypertensive disorders of pregnancy," says the report. The team says additional information is needed to distinguish medical conditions that developed before pregnancy from those that developed during pregnancy and to determine whether this distinction affects clinical outcomes of Covid-19.
Symptom status was reported for 65.2% of pregnant women and 90% of nonpregnant women: 97.1% of pregnant and 96.9% nonpregnant women reported being symptomatic. "Data on symptom status were missing for approximately one-third of pregnant women, compared with 10% of nonpregnant women. Therefore, if those with missing symptom status are more likely to be asymptomatic, the percentage of asymptomatic pregnant women could be higher than the percentage of asymptomatic nonpregnant women," the findings state.
Symptomatic pregnant and nonpregnant women also reported similar frequencies of cough (51.8% versus 53.7%) and shortness of breath (30.1% versus 30.3%). Pregnant women less frequently reported headache (40.6% versus 52.2%), muscle aches (38.1% versus 47.2%), fever (34.3% versus 42.1%), chills (28.5% versus 35.6%) and diarrhea (14.3% versus 23.1%) than nonpregnant women did. "The percentages of pregnant women reporting fever, muscle aches, chills, headache and diarrhea were lower than those reported among nonpregnant women, suggesting that signs and symptoms of Covid-19 might differ between pregnant and nonpregnant women," say experts.
The American College of Obstetricians and Gynecologists (ACOG) released a statement, noting that the new information released by the CDC "suggests a different level of risk for pregnant patients than was previously indicated by earlier data". "New information from the CDC suggests that pregnant patients may be at increased risk for certain manifestations of severe illness due to Covid-19, such as intensive care unit admission and mechanical ventilation. Importantly, the available data also suggest that the overall risk of these clinical interventions remains low and that pregnant patients do not appear to be at increased risk of death associated with Covid-19 compared with nonpregnant patients in the same age group," it said.
According to ACOG, the study highlights the importance of pregnant patients being prioritized for a coronavirus vaccine once it becomes available. "ACOG again urges the federal government to use its resources to ensure the safe inclusion of pregnant and lactating patients, including patients of color, in trials for vaccines and therapeutics to ensure that all populations are included in the search for ways to prevent and treat Covid-19," says the association. It adds, "As the pandemic continues, ACOG urges its members to encourage pregnant patients, who test positive for Covid-19, to consider enrolling in an appropriate Covid-19 registry to help the medical community better understand the impact of Covid-19 on pregnancy outcomes."