Covid-19 during Pregnancy – Histopathological Lesions of the Placenta

Abstract

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.

Key words

SARS-CoV-2 - Covid-19 pandemic - Covid-infection during pregnancy - histopathological changes of the placenta

Publication History

Received: 01 June 2023

Accepted after revision: 10 September 2023

Article published online:
02 November 2023

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