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The 38-year-old mother had experienced a complicated pregnancy, made riskier by Type 2 diabetes and a liver condition that causes bile to build up in the blood. On March 19, in her 37th week, she went to Columbia University Medical Center in New York City to be induced. Neither she nor her husband reported any of the worrisome symptoms that health care providers are watching for to screen for COVID-19, such as fever, cough, shortness of breath or sore throat. In fact, the woman’s temperature was slightly below normal, at 98.4 degrees Fahrenheit.

Then, while the woman was in labor, her temperature climbed to 101.3. Suspecting that she had developed a potentially dangerous bacterial infection called chorioamnionitis, her care team gave her antibiotics and acetaminophen, which seemed to stabilize her. But labor was progressing slowly, and doctors decided to perform a cesarean section. As they were stitching up their patient, she began to hemorrhage uncontrollably. The team raced to intubate her, but her breathing rapidly worsened. When doctors finally had her condition under control, they decided to evaluate her for COVID-19. She tested positive.

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The woman, whose case was described in a short report published Thursday in the American Journal of Obstetrics and Gynecology, is one of seven pregnant patients at CUMC in recent days who turned out to have the coronavirus. Two of those women had no apparent symptoms when they arrived at the hospital, only to deteriorate soon after giving birth; both required admission to the intensive care unit.

CUMC is part of the NewYork-Presbyterian medical system, which announced on March 22 that it would no longer allow women who come to the system to give birth to bring in outside support to help them through labor and recovery — no husbands, no sisters, no doulas. Some 25,000 women give birth in the system’s eight maternity hospitals every year.

That decision, which has since been joined by the Mt. Sinai health care system, has sent shock waves through the birthing community around New York City, where about 117,000 babies were born in 2017. The report provides new insight into why the two hospitals decided to take such a controversial step — and why other medical systems are grappling with some of the same wrenching issues.

“While this [no-visitor] policy might seem Draconian,” the report said, “it should increase the protection of the mothers we care for, their infants, and the obstetric care team, by recognizing what series like this teach us: there is currently no easy way to clinically predict COVID-19 infection in asymptomatic people.”

Mary D’Alton, chair of the department of obstetrics and gynecology at CUMC, said: “The decision to not permit visitors, including birthing partners and support persons, to be with our obstetric patients was extremely difficult, but it is critical for the health and safety of our mothers, babies, all the families we take care of and our care teams. I never thought we’d be faced with having to make a decision like this in my lifetime, but as with all of the measures we have taken to reduce the spread of COVID-19, our ability to try to prevent potential exposure is essential.”

Read More What Coronavirus Means for Pregnancy, and Other Things New and Expecting Mothers Should Know The experience you expected is likely to be very different from the one you actually get. The key to staying sane is to be as ready as possible to throw your best-laid-plans out the window.

The risks for women and babies exposed to COVID-19 are only beginning to be widely studied. At the moment, based on a very small sample of reported cases from China, public health officials believe that pregnant women are not at higher risk for contracting the virus, but many experts worry that expectant mothers may be more vulnerable to severe respiratory illness because of pregnancy-related changes to the lungs and immune system. It is currently believed that pregnant women do not transmit the virus to the fetus, but new studies from China looking at the illness in newborns and children have made many providers uneasy. So far, there have been no reported maternal deaths attributed to COVID-19.

A total of four of CUMC’s pregnant patients required hospitalization, according to the report, whose lead author is maternal-fetal specialist Noelle Breslin. But it’s the asymptomatic women who may hold the most urgent lessons for a maternal care system that is scrambling to reinvent itself as the pandemic unfolds.

In the case of the 38-year-old mother, “an estimated 15 healthcare providers were exposed to this patient prior to diagnosis, including during intubation, all with inadequate personal protective equipment,” the report said.

The second asymptomatic mother-to-be, a 33-year-old who had a C-section, also was having an extremely complex pregnancy; she was admitted for an induction on March 18 at 37 weeks because she had been suffering from chronic hypertension, asthma and diabetes. The surgery went off without a hitch and her baby was fine. She did not begin exhibiting COVID-19 symptoms until 25 hours after she delivered, or more than 60 hours after showing up at the hospital with her husband. Over that period, the study’s authors said, “An estimated 15-20 healthcare providers were exposed to this patient, again without adequate [personal protective equipment] prior to diagnosis.”

Both newborns were placed in an isolation nursery after their mothers tested positive, and both babies tested negative for the virus. The 38-year-old was released after four days, but the other woman remained hospitalized as of the report’s release.

The report’s authors sounded a call to action. “This limited initial US experience suggests a need for immediate changes in obstetric clinical practice,” the study’s authors wrote. They noted that of the seven pregnant women with confirmed COVID-19, five didn’t have a fever when they arrived at the hospital and four didn’t report the other symptom widely used to screen potential cases, a cough.

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Nearly 4 million women give birth to nearly 4 million babies in the U.S. every year, a potentially challenging influx of mostly healthy patients into the medical system at a time when it’s coming under unprecedented stress. Unlike some other types of providers, OB-GYN providers can’t be easily replaced by doctors and nurses from other parts of the system, particularly those who work with high-risk pregnant women.

Yet obstetrical care providers “are at particularly increased risk for occupational exposure,” the report said, “because of long periods of interaction with patients during labor, multiple team members involved in patient care, and the unpredictable occurrence of sudden obstetrical emergencies with their potential for unanticipated intubations in women undergoing labor and delivery. Given this risk, and without universal rapid viral testing, we must acknowledge that every admission and delivery present[s] real risk for infection to our front-line healthcare workers.”

“Until adequate PPE supplies exist,” the report said, “we can reasonably expect our obstetrical and anesthesiology providers to become ill and exit the workforce at an accelerated rate.”

Update, March 27, 2020: This story was updated to include new comment from CUMC.

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