A second-trimester miscarriage in a Covid-19 patient was attributed to a placental infection of the virus, according to new research, as some obstetricians notice an uptick in still births since the coronavirus pandemic hit the U.S.
Reports of newborns with fetal distress and stillbirth after maternal contraction of the virus during the third trimester suggest that there may be a Covid-19 induced placental infection, according to the research published Thursday in the Journal of the American Medical Association.
"This case of miscarriage during the second trimester of pregnancy in a woman with COVID-19 appears related to placental infection with SARS-CoV-2, supported by virological findings in the placenta," the researchers said.
A pregnant woman in her second trimester was seen at Lausanne University Hospital with a fever of 102.5 degrees, muscle pain, fatigue, mild pain with swallowing, diarrhea and dry coughs after contracting the coronavirus. Two days after she tested positive and was prescribed pain relievers, she returned to the hospital with severe uterine contractions, a fever and no improvement of her symptoms.
After 10 hours of labor, she delivered a stillborn baby on March 20. While her nasopharyngeal swab had been previously tested positive for Covid-19, her blood and vaginal swabs sampled during labor were both negative.
The doctors also collected swab samples from the infant's mouth, armpit, feces and blood within minutes of birth and their results also came out negative.
However, two swabs and biopsies obtained from the fetal surface of the placenta close to the umbilical cord were tested positive for Covid-19. These findings suggest that the miscarriage in this Covid-19 patient may be attributed to placental infection of the virus.
Researchers concluded that the fetus wasn't infected, but the mother and placenta were. They also could not identify any other possible causes of miscarriage.
"Absence of the virus is not surprising given the stage of fetal development and short time of maternal infection," the researchers said. "Whether SARS CoV-2 crosses the placental barrier warrants further investigation."
The report from JAMA also noted that infection of the maternal side of the placenta resulting in miscarriage or impediment of fetal growth was observed in 40% of cases of pregnant patients with MERS and SARS, or severe acute respiratory syndrome, which are both coronaviruses.
A separate study published in The Lancet showed that in a review of 12 pregnant women who were infected with SARS during the 2002 to 2003 pandemic, 57% of women in their first trimester had a miscarriage. In the second to third trimester, 40% had fetal growth restriction and 80% had preterm birth.
As the global pandemic continues to infect tens of thousands of people across the world, pregnant mothers are increasingly put at risk.
U.S. obstetricians have been seeing an increased rate of miscarriages in their patients, according to Dr. Jane van Dis, MD, board certified OB-GYN practicing in La Cañada, California.
Van Dis told CNBC that one of her colleagues recently witnessed 18 spontaneous miscarriages in three weeks, while another practitioner saw five miscarriages in two weeks. She added that these physicians were finding increased terms in fetal demise, meaning pregnant mothers in their third trimester were experiencing miscarriages.
Van Dis said researchers and doctors are seeing more cases of blood clots in lungs, hearts and kidneys of coronavirus patients.
"The placenta is made up of miles and miles of blood vessels. Anything that causes clots in the placenta is going to diminish oxygen for the embryo or the fetus and put the fetus at an increased risk of demise," she said.
Van Dis conducted her own informal survey, asking 210 obstetricians if they've observed a higher number of miscarriages with regards to the coronavirus.
The results showed 42% increase in first trimester loss, 20% increase in second trimester loss and 21% increase in third trimester loss. They aren't sure whether Covid-19 played a role in the miscarriages because many of their patients didn't have symptoms and weren't tested.
She said doctors need to test more pregnant women for Covid-19 as there is "a huge number of asymptomatic positive cases."