NEW FINDING

Coronavirus can cause ‘placenta injuries’ in pregnant women, doctors warn

PREGNANT women who have had coronavirus may need closer monitoring, doctors have warned.

It comes as a small study showed the disease could cause "injuries" to the placenta - which acts as the foetus' ventilator.

⚠️ Read our coronavirus live blog for the latest news & updates

However, they have reassured mums-to-be that these injuries do not appear to harm an unborn baby.

Researchers examined the placentas of 16 women who had tested positive for the virus while pregnant.

Pathological exams showed evidence of injury to the placenta.

But, notably, the team said there didn't appear to be negative outcomes for newborns but added that mums-to-be with a history of coronavirus may need closer monitoring.

The Royal College of Obstetricians and Gynaecologist has highlighted that most pregnant women with coronavirus have had normal and healthy pregnancies - and the outlook for newborns is good.

They also highlighted that pregnant women are at no greater risk because of Covid-19 and that there is no evidence that it may increase miscarriage rates.

Abnormal blood flow

The new study, published in the American Journal of Clinical Pathology, stated that the new injury could cause an abnormal blood flow between mothers and their babies.

The authors stated that the new findings raise concerns as to how pregnant women are being monitored through the pandemic.

Dr Emily Miller, from Northwestern University, said while she didn’t want to “paint a scary picture” the findings did “worry” her.

"I don't want to draw sweeping conclusions from a small study, but this preliminary glimpse into how Covid-19 might cause changes in the placenta carries some pretty significant implications for the health of a pregnancy.

"We must discuss whether we should change how we monitor pregnant women right now."

From the limited data set, the Dr Miller's team found that the virus was causing some injury to the placenta, but added those injuries didn't appear to have negative outcomes in live-born infants.

Dr Miller said the study shows the placenta may not being doing its job to full capacity in women who have Covid-19

She added:"The placenta acts like a ventilator for the foetus, and if it gets damaged, there can be dire outcomes.

"In this very limited study, these findings provide some signs that the ventilator might not work as well for as long as we'd like it to if the mother tests positive for SARS-CoV2."

Dr Miller said that there is a risk that some pregnancies could be “compromised” because of this and stated that blood had been blocked off in some cases, making it hard for the placenta to grow.

Closer monitoring

The placenta acts as a ventilator to the unborn baby and the development could mean that women are monitored more closely if they test positive for Covid-19.

This could include a non-stress test which looks at how effectively the placenta is delivering oxygen.

Dr Jeffrey Goldstein added that flu-like viruses do not cross into the placenta, and said that whatever is causing problems is due to immune activity injury in the placenta.

Of the 16 patients involved in the study, 15 delivered in the third trimester and one miscarried on the second.

The researchers however did highlight that the patient who miscarried was asymptomatic, so there was no indication whether this had happened because of the virus.

Commenting on the findings of the study Professor Marian Knight, Professor of Maternal and Child Population Health, University of Oxford said it was important to note that the majority of women had normal pregnancies.

“This small study showed differences in the appearance of the placenta amongst some women with SARS-CoV-2 infection compared to women who had placental examination for other reasons.

"It is unclear what proportion of women with infection had their placentas examined, whether the women had current or past infection, or whether they had other indications for placental examination, and therefore whether the differences observed could be causally linked to COVID-19 infection.

“Importantly, the majority of the women had normal term pregnancies and healthy babies, and thus the significance of these pathological findings are unclear.

"Women should be reassured by the findings of much larger studies, which have not suggested higher risks of problems for babies due to placental complications.”