TUESDAY, April 14, 2020 (HealthDay News) -- A study of pregnant women admitted to two New York City hospitals for delivery in late March and early April found that about 1 in 7 were infected with the new coronavirus and most didn't show symptoms.
Reporting April 13 in the New England Journal of Medicine, doctors from New York-Presbyterian Allen Hospital and the Columbia University Irving Medical Center said they tested a total of 215 women who delivered newborns between March 22 and April 4.
All were tested for the new coronavirus upon admission to the hospital, and 33 tested positive for infection with COVID-19.
Most of those potentially harmful or transmissible cases would've been missed if the women hadn't been tested, said a team led by Dr. Dena Goffman, of Irving Medical Center.
In fact, "29 of the 33 patients [87.9%] who were positive … at admission had no symptoms of COVID-19 at presentation," Goffman and her colleagues noted. Only four of the 33 patients displayed typical COVID-19 symptoms, such as fever.
Many of the women did not go on to develop symptoms either, at least over the short term. Of the 29 asymptomatic obstetric patients, only three went on to develop any fever during the few days they were in the hospital, and it's not even clear if the fevers were related to COVID-19 or some other condition.
The bottom line, according to the New York City physicians who penned the report, is that all women admitted to the hospital for obstetric care should be tested for the novel coronavirus.
Doing so could help "determine hospital isolation practices and bed assignments" for individual patients, and help in the care of newborns and the "use of personal protective equipment" by hospital staff, Goffman's group said.
"The new data provides an important opportunity to protect mothers, baby and health care teams during these challenging times," the study authors said.
Dr. Natalie Meirowitz is chief of obstetrics and gynecology/maternal fetal medicine at Long Island Jewish Medical Center in New Hyde Park, N.Y. Reading over the study findings, she said the rate of coronavirus infection for pregnant women "probably varies quite a bit between communities."
And she added that "the women they report as asymptomatic women may have been 'pre-symptomatic' -- developing symptoms only after discharge from the hospital."
Also, Meirowitz said, "from our experience, there are women we initially classified as asymptomatic, that subsequently recalled minor symptoms such as low grade fever or dysgeusia [loss of sense of taste] in days/weeks preceding the positive test results."
And what about any risks to the fetus and newborn? Most reports say there's a low risk of the coronavirus being transmitted from an infected mother to her fetus, according to Dr. Justin Brandt, an assistant professor of obstetrics and gynecology in the division of maternal-fetal medicine at Rutgers Robert Wood Johnson Medical School in New Jersey.
However, there is some research suggesting that some newborns of mothers with COVID-19 have coronavirus-specific antibodies, suggesting they were exposed to the virus in the womb.
"We need more data to clarify and corroborate this risk, but there may be reason to worry about vertical transmission and associated conditions, including birth defects, early neonatal disease and other complications," Brandt said in a Rutgers news release.
In the meantime, women who are pregnant should take special care to avoid infection, he said.
To reduce their risk of infection, pregnant women should practice social distancing, stay home and avoid public gatherings. If they must leave home, they should wash their hands regularly, try not to touch their face, and stay at least 6 feet from people who may be sick or people whose statuses are unknown, Brandt advised.
He said expectant parents should prepare to be home for several months and be stocked up on food, common medicines including Tylenol, thermometers and other household items such as soap, toilet paper and washing detergent.
When possible, use delivery services rather than going to markets and other stores where there may be groups of people, Brandt said.
The U.S. Centers for Disease Control and Prevention has more on the coronavirus and pregnancy.
SOURCES: Natalie Meirowitz, M.D., chief, obstetrics and gynecology/maternal fetal medicine, Long Island Jewish Medical Center, New Hyde Park, N.Y.; Rutgers Robert Wood Johnson Medical School, news release, March 27, 2020; New England Journal of Medicine, April 13, 2020