Impact of COVID-19 infection on placental histopathology and maternal-perinatal outcomes: A cross-sectional study.

Abstract

Background: Coronavirus disease 2019 (COVID-19) presents a broad spectrum of clinical outcomes and, unlike other coronaviruses, poses significant risks during pregnancy. A primary concern is the potential for vertical transmission from mother to fetus, affecting both maternal and fetal health.

Objective: This study aimed to investigate the placental histopathology and maternal-perinatal outcomes in mothers infected with COVID-19.

Materials and methods: In this cross-sectional study, 40 pregnant women referred to Ganjavian hospital, Dezful, Iran for delivery from June-October 2021 were enrolled in 2 groups: group I who were women with COVID-19 on the day of delivery (n = 30) and group II who were women without COVID-19 (n = 10). Placental tissue samples were collected post-delivery to assess histopathological changes and placental weight. Additionally, maternal and neonatal characteristics including maternal age, the number of prior deliveries and pregnancies, gestational age, 1- and 5-min Apgar scores, and maternal oxygen administration, mode of delivery, and neonatal COVID-19 test results, were compared between the groups.

Results: No significant differences were found between the groups regarding maternal age, gestational age, parity, Apgar scores, placental weight, oxygen therapy, or delivery method. However, group I showed significantly higher rates of placental abnormalities such as intravillous fetal thrombosis (p = 0.002), fibrin deposition, lymphocytic infiltration, chorangiosis, edema, intervillous hemorrhage, syncytial node formation, distal villous hypoplasia, and avascular villi (p $<$ 0.001).

Conclusion: According to our study, the placental tissue of pregnant women who have been infected with COVID-19 during their third trimester indicates tissue changes that can lead to poor exchanges between mother and fetus.