Getting COVID while pregnant increases your risk of severe illness and, in turn, pregnancy complications like preterm birth and preeclampsia. While the reasons for this are multifactorial, numerous studies have sought to understand how – and why, exactly – COVID can affect a pregnancy.
One team of researchers from Henry Ford Health thought answers might be found in the placenta, as the placenta can often reveal a lot about a pregnancy.
“The placenta is an organ that grows during pregnancy and delivers oxygen and nutrients to the baby,” says Ghassan Allo, M.D., a pathologist at Henry Ford Health. “A healthy placenta is key for a healthy baby. Any time a woman delivers and there’s an abnormality – the mother has an illness, the baby isn’t healthy, there’s a complication before or during delivery – the placenta is examined to understand why this occurred.”
Comparing The Placentas Of COVID Positive And Negative Mothers
Dr. Allo and his team examined the placentas of a group of women with and without COVID to see how they differed. This was at the start of the pandemic, from April 2020 – June 2020.
“During those first few months, it became clear that COVID wasn’t just a respiratory disease – it could damage all of the organs,” says Dr. Allo. “It could lead to inflammation in the blood vessels, causing blood clots and limiting oxygen to the brain and heart – not just the lungs. We wondered if it could do the same to the placenta. We expected to find some changes in the blood vessels of the placenta – yet we found this wasn’t the case.
Obstetrics At Henry Ford
“This could mean one of many things. Either the virus did not affect the placenta in our group of mothers – or at least didn’t cause any biological changes we could see – or the virus didn’t make it to the placenta. Maybe the inflammation that can occur with COVID did not affect the placentas in our group of mothers.”
Dr. Allo did find, however, that in COVID positive mothers, the umbilical cord was more likely to be inserted on the margins of the placenta rather than at the center. In certain instances, this could slow the growth of a fetus, or in delivery, it could cause the umbilical cord to be ruptured or squeezed. But this is likely an incidental (or unrelated) finding.
“The umbilical cord forms during early pregnancy, and all of these mothers had COVID in late pregnancy,” says Dr. Allo. “COVID wasn’t around when they were in early pregnancy.”
Research that studied pregnant women later on in the pandemic, however, did find differences in the placentas of COVID positive mothers: One study published in the American Journal of Obstetrics & Gynecology found that a COVID infection decreases the placenta’s immune response to fend off future infections, potentially affecting fetal development. Another found that COVID can affect placental blood vessels, potentially limiting transportation of oxygen from mother to fetus. And yet another found that COVID can cause inflammation in the placenta – especially variants, like the Delta variant. (At the time Dr. Allo conducted the study, there were no variants – just the original strain.)
Protecting Yourself From Viruses When Pregnant
Whether it’s COVID, the flu or RSV, it’s important to be vigilant about protecting yourself from contracting any virus while pregnant. While some pregnant mothers will fortunately be perfectly fine, the seriousness of viruses varies from person to person, sometime inexplicably.
That’s why the CDC recommends pregnant people receive vaccinations for COVID, the flu and RSV. These vaccines may pass antibodies along to your baby, too, protecting them from infection after they are born.
Reviewed by Ghassan Allo, M.D., a specialist in pathology at Henry Ford Health.
