The study will be published in the journal Obstetrics & Gynecology. This is the first study to examine the impact of the COVID vaccines on the placenta.
“We have reached a stage in vaccine distribution where we are seeing vaccine hesitancy, and this hesitancy is pronounced for pregnant people,” said study co-author Dr. Emily Miller, Northwestern Medicine maternal fetal medicine physician and assistant professor of obstetrics and gynecology at Feinberg.
“Our team hopes these data, albeit preliminary, can reduce concerns about the risk of the vaccine to the pregnancy.”
Placentas were taken from 84 vaccinated patients and 116 unvaccinated patients who delivered at Prentice Women’s Hospital in Chicago and pathologically examined the placentas whole and microscopically following birth. Most patients received Moderna or Pfizer vaccines during their third trimester.
Pregnant patients who want to get vaccinated to avoid contracting the disease should feel safe doing so, Miller said.
“We are beginning to move to a framework of protecting fetuses through vaccination, rather than from vaccination,” Miller said.
Previous studies found that placentas of women who tested positive for the COVID-19 virus while pregnant showed evidence of injury. And, pregnant women make COVID antibodies after vaccination and successfully transfer them to their fetuses.
“Until infants can get vaccinated, the only way for them to get COVID antibodies is from their mother,” Goldstein said.
Placenta helps fetus’ organs form and provide oxygen while the lungs develop and nutrition while the gut is forming. It manages hormones and the immune system, and tells the mother’s body to welcome and nurture the fetus rather than reject it as a foreign intruder.
“The Internet has amplified a concern that the vaccine might trigger an immunological response that causes the mother to reject the fetus,” Goldstein said. “But these findings lead us to believe that doesn’t happen.”
Abnormal blood flow between the mother and fetus and problems with fetal blood flow is also assessed in pregnant patients who have tested positive for COVID. The rate of these injuries was the same in the vaccinated patients as for control patients, Goldstein said.
Scientists also examined the placentas for chronic histiocytic intervillositis, a complication that can happen if the placenta is infected, in this case, by SARS-CoV-2.
Larger sample size may be required to differentiate between vaccinated and unvaccinated patients.
Source: Medindia
