Covid-19 can damage placenta in pregnant women

Covid-19 damaged the placenta in a number of pre-term births in the Netherlands during the first and second wave of coronavirus infections, researchers at Erasmus MC and LUMC found. Worryingly, pregnant women don't notice that their placenta is affected, and it is impossible to detect on the ultrasound, while it could put the unborn child at serious risk. "It is important that pregnant women get vaccinated to protect themselves and their unborn child," Gynecologist-perinatologist Sam Schoenmakers said on the Erasmus MC website.

This study was launched after a pregnant woman came to Erasmus MC with a runny nose. Her baby was found to be in distress and ended up being delivered with an emergency cesarean section eight weeks early. After the birth, the doctors found that the woman's placenta was severely damaged by Covid-19. Schoenmakers then decided to test the placentas of all pregnant women who had the coronavirus in the first in second wave.

The researchers found a clear "placental Covid-19 signature" in five of the 36 studied placenta - they found dead cells (necrosis), hardening (fibrin deposit), and immune cells that normally never occur in the placenta.

"The placenta ensures the exchange of substances, such as oxygen, between mother and child and protects the fetus against diseases. When the placental cells die from a coroanvirus infection, the system becomes clogged. This can lead to oxygen deficiency, extreme distress or even death of the child," Schoenmakers said on the Erasmus MC site. "What makes it very difficult is that women don't feel when the placenta is infected. We saw a mother who herself hardly noticed Covid-19 and yet had an infected, seriously ill placenta. Nothing showed up on the ultrasound either. So we don't know in advance which women are at risk."

Schoenmakers acknowledged that this is scary news for expectant mothers and therefore urged them to get vaccinated against Covid-19, if they haven't already had their shots. "It is important that everyone is vaccinated. Young mothers too: vaccination helps to prevent coronavirus infection and to protect yourself and your unborn child."