麻豆传媒

CHICAGO -- The developing fetuses of pregnant women with mild to moderate cases of COVID-19 did not appear to be harmed by the disease, a researcher reported.

In the study of 33 pregnant women who had SARS-CoV-2 infection, magnetic resonance imaging (MRI) showed normal brain development, including brain stem segmentation and cortical folding, said Sophia Stöcklein, MD, of Ludwig Maximilian University of Munich.

"Women infected with SARS-CoV-2 during pregnancy are concerned that the virus may affect the development of their unborn child, as is the case with some other viral infections," Stöcklein said in a presentation at the , conducted this year both in person and online. "So far, although there are a few reports of vertical transmission to the fetus, the exact risk and impact remain largely unclear. The aim of our study was to fill this gap in knowledge regarding the impact of a maternal SARS-CoV-2 infection on fetal brain development."

Women in the study were about 28 weeks into their pregnancies. On average, COVID-19 symptom onset occurred at just over 18 weeks into pregnancy, and included loss or reduced sense of smell and taste, dry cough, fever, and shortness of breath.

Two board-certified radiologists experienced in fetal MRI evaluated the scans and found that the brain development in the assessed opercularization of the Sylvian fissure, the cortical folding, and the transverse cerebellar diameter were age-appropriate in all fetuses, Stöcklein said. Compared with an independent age-cohort, anteroposterior diameter and craniocaudal extent of pons, medulla oblongata, midbrain, and cerebellar vermis were all within age-appropriate limits, she added.

No calcifications, edema, or ventricular enlargement were detected. Seven fetuses showed mild asymmetry of the lateral ventricles with a maximum difference of 4 mm, and there were no findings indicative of infection of the fetal brain.

"In our study, there was no evidence that a maternal SARS-CoV-2 infection has any effect on the brain development of the unborn child," Stöcklein said. "This fact should help to reassure affected parents."

She cautioned, though, that the study included only mothers with mild to moderate symptoms and who had not been hospitalized.

"As a first step, this is definitely good news," commented Gregor Kasprian, MD, of the Medical University of Vienna. "Maternal infection with SARS-CoV-2 can increase risk of miscarriage, preterm birth, and stillbirth, which is likely due to damage to the placenta. Abnormal placental function can negatively affect brain development."

"This does not mean that subtle changes in fetal brain growth can be excluded," he told 麻豆传媒. "Especially in pregnant women with severe clinical course of the disease, abnormal placental function could influence brain growth."

Kasprian suggested that "a higher number of subjects and especially cases with a severe clinical course of the disease need to be studied to fully understand the consequences of SARS-CoV-2 infections on fetal brain growth."

Stöcklein explained that since the impact of severe infection on brain development in the fetus has not been conclusively determined, active protection against SARS-CoV-2 infection during pregnancy remains important.

"So far, vaccination is the most promising protection against COVID-19," she said. "Any potential side effects are manageable, even in pregnant women. Therefore, despite the encouraging results of our study, pregnant women should strongly consider vaccination."

As part of the study, Stöcklein and her colleagues will be following the study participants over the next 5 years and conducting detailed neonatal assessment and assessing children's neurological development.

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