Introduction Pregnant women and their offspring represented a vulnerable
patient collective during the Covid-19 pandemic. Beyond the direct effect of
SARS-CoV-2 via vertical transmission, an indirect impact on the fetus can occur
through placental lesions deteriorating placental villous function. We performed
a histopathological analysis of placentas of parturients with SARS-CoV-2
compared to healthy controls.
Methods and materials Between February 2022 and July 2022 we conducted a
prospective case–control study analyzing placental specimens of
parturients with SARS-CoV-2 infection compared to specimens of placentas of
healthy controls. Patient history, Covid-19-specific symptoms, and obstetric
outcomes were recorded. Statistical analysis was performed.
Results During the observation period 71 patients were included with a
gestational age 37 1/7–41 5/7 weeks. Thirty-six patients
presented with SARS-CoV-2 infection. The control group consisted of 35 patients
and showed no placental abnormalities. Among SARS-CoV-2-positive parturients,
66.7% of placentas of the case group showed histopathological
abnormalities classified as vascular or inflammatory abnormalities.
22.2% of placentas showed acute ischemic infarction areas. 8.3%
of placentas showed subchorionic layered thrombi. There was one case of severe
acute subchorionitis. SARS-CoV-2 increased the risk of placental lesions
significantly (OR 3.000, CI 1.890–4.762, p=0.0001). Placental
lesions had no significant impact on perinatal acidosis (OR 0.455, CI
0.044–4.667, p=0.498) or number of cesarean sections (OR 2.314,
CI 0.717–7.473, p=0.156).
Conclusion SARS-CoV-2 infection during labor and delivery increased the
risk of adverse outcomes. Histopathological analysis indicated that the placenta
as a maternal-fetal interface was affected by SARS-CoV-2, leading to systemic
vasculopathy and inflammation.