Mothers infected with COVID-19 can transfer the disease to the placenta and baby resulting in stillbirth, a new study by researchers from Samson Assuta Ashdod University Hospital found.
In some cases of stillbirth, a higher level of the virus was found in the fetus than even in the sick mother. And, in all cases, substantial damage to the placental tissue was found.
The study was led by Prof. Eran Barzilay, head of the Obstetric and Gynecological Ultrasound Unit at Assuta. He explained that according to multiple studies conducted internationally, there is a two-fold increase in the risk of fetal death during pregnancy in women with coronavirus versus those who do not have the disease. However, until now, no study had been conducted examining what causes this.
The team started by identifying four women, Assuta patients whose fetuses had died at the same time as they were diagnosed with the virus. They then ran pathological tests of the placenta and did PCR tests of the mother, fetus and placenta. In all cases, they saw that the virus had infected the placenta and the baby, including causing extensive damage to the placental tissue, which Barzilay said they believe was the reason for the fetal death.
“There are several viruses that can cause infection of the fetus when the mother is infected,” the professor said. “But we have never seen this kind of damage to the placenta from a virus. It seems to be something specific to corona.”
He added that what was striking was that “even if the mother had very mild disease and mild symptoms and her PCR test was positive but showed low levels of viral infection, the placenta has a high viral load.”
The researchers compared the placentas of the women who lost their babies to those who did not but who were also diagnosed with COVID, and found that there was no corona in the placentas feeding the live babies.
“We can say that infection did cause fetal death and that the death was caused directly by the placenta,” Barzilay stressed.
None of the women who lost their babies were vaccinated.
The study was accepted for publication by the International Journal of Gynecology and Obstetrics.
Barzilay said fetal death is very rare, so even if multiplied by two, it does not have a major impact on the population. He said that it is another reason for mothers to protect themselves from the disease.
He added that COVID-19 can pose a severe risk to pregnant women, especially in their third trimester, and that the country and the world saw many pregnant women develop severe disease. These women were often forced to deliver their babies prematurely, which could cause developmental challenges or even be life-threatening.
A separate study found that women who vaccinate can pass on some immunity to their newborns. Barzilay said although there are few cases of infants who develop severe disease, getting vaccinated gives newborn babies “an added benefit.”