There are already many reasons to be concerned about COVID-19, but there is another to add to the list: there is evidence of the virus in fetal brain tissue in cases of pregnant women transmitting the virus. infection to their children.
So it’s not just the effects of the disease on our bodies that are of concern, but also the effects on the bodies of unborn babies – something scientists have already urgently studied.
The team studied 661 human fetal tissue samples taken between July 2020 and April 2022, observing hemorrhages in 26 of them. COVID-19 was present in all tissue samples with signs of hemorrhage.
All samples were collected from electively terminated pregnancies.
“Although haemorrhages occasionally occur in developing brains, it is extremely unusual that there are so many cases over a 21-month period,” says neurobiologist Katie Long from King’s College London in the UK.
“It is now of utmost importance that we follow up children who were exposed to COVID-19 before birth so that we can establish if there are any lasting neurodevelopmental effects.”
The researchers pointed to signs of reduced blood vessel integrity and increased immune cells infiltrating the brain as being linked to tissue damage. This may be the direct result of COVID-19 infection or an indirect result of the mother’s immune response.
Although the coronavirus has only been confirmed in fetal tissue, it is safe to assume that the infections were transferred from an infection in their mothers. It’s unclear whether the hemorrhage was a direct result of the mother’s COVID or infection of the fetus – or whether the relationship involves an unknown factor. But the link is strong enough to be concerning.
Additionally, most samples with evidence of hemorrhage were from the late first and early second trimester of gestation, suggesting that the fetal brain may be affected in the early stages of its development. We already know that this is a crucial time for the developing brain, as it creates barriers to defend itself.
“We know that severe viral infection can influence the brain of the fetus, but this important study is the first to suggest this can occur in pregnancies affected by COVID infection,” says physiologist Lucilla Poston of King’s College of London. Poston was not involved in the study.
“Whatever the cause, direct effect of the virus or indirect consequence of maternal infection, this study highlights the need for pregnant women to be vaccinated against COVID-19, thus avoiding complications for the mother. and the baby.”
Traces of SARS-CoV-2 have also been detected in tissue samples taken from the placenta, amnion and umbilical cord, suggesting that there is potential for additional complications caused by the presence of COVID-19 .
Viral infections in mothers are regularly associated with neurological damage in children; the Zika virus is one of the most publicized cases in recent years, showing how important these effects can be.
We have previous studies linking health problems in fetuses to COVID-19 cases in pregnant women, but so far the pool of data on the subject is relatively small – something scientists will seek to change in the future.
“Our results suggest that there is an association between early development of human fetal brain tissue and susceptibility to COVID-19 infection,” says neurobiologist Marco Massimo from King’s College London.
The research has been published in Brain.