Study reveals Covid-19 harm to placenta and developing fetus

Using prenatal MRI, a team of researchers examined the placenta and fetus of women who tested positive for SARS-CoV-2 during pregnancy.

The results showed that different mutants of the virus that appeared during the pandemic led to varying degrees of damage, especially in mutants before Omicron, and the identified placental lesions could harm the development and health of some fetuses.

Although such damage occurs infrequently and less severely with currently circulating Omicron submutants, the study authors remain advocating measures for the early detection of pregnant women who test positive for the coronavirus.

Unlike previous studies in which malformations associated with SARS-CoV-2 were detected only after birth and/or through histopathological procedures, the MedUni Vienna team focused on prenatal imaging findings.

Using prenatal magnetic resonance imaging (MRI), 76 scans of the placenta and fetuses of pregnant women were performed in the study: 38 scans after confirmed infection with SARS-CoV-2 (pre-Omicron or Omicron mutants) and 38 scans from healthy controls. .

The team found that the placenta in both the pre-Omicron and Omicron groups showed abnormalities.

“Infection with pre-micron mutants such as Delta resulted in significantly more damage in the form of vascular events such as clots or bleeding than pre-micron sub-micron mutants currently found in the population.

It can be concluded that the fetuses of infected pregnant women more often developed endopathy and intrauterine growth retardation (poor growth of the fetus in the womb during pregnancy) or vascular lesions of the organs and brain in the early stages of the epidemic.

Fewer placental abnormalities in vaccinated women

The researchers attribute the varying degrees of damage to the placenta by different variants of the virus to the fact that Omicron submutants are less likely than their predecessors to cause serious disease, and to higher vaccination rates as the epidemic progresses.

“Our results showed that unvaccinated study participants developed placental abnormalities after being challenged with the Omicron variant, compared with only one in six women who received three doses of the vaccine,” said senior author Gregor Kasprian, also from the Department of Biomedical Imaging and Image Targeted Therapy. .

The exchange of oxygen, nutrients and metabolic products between mother and child takes place in the placenta. Attached to the wall of the uterus, this organ forms a powerful barrier against coronavirus: 3% or less of fetuses whose mothers test positive for SARS-CoV-2.

But as the study showed, the placenta itself did not escape the complications caused by Covid-19. After this, some unborn children experience growth retardation or cerebral hemorrhage.

“That’s why it’s important to examine the placenta of pregnant women with SARS-CoV-2 as soon as possible after a positive infection test using prenatal imaging techniques,” advises Daniela Breuer from the Department of Biomedical Imaging and Imaging Therapy.

The results of the study are published in The Lancet Regional Health – Europe.

Source: Medical Express