Impact of SARS-CoV-2 Omicron infection on late pregnancy: an analysis of clinical characteristics, pathology of placenta and outcomes in a case-control study
Heping Zhang, Hongliang Xu, Shuguang Zhou, Yong Chen, Qin Wang, Caixia Zhao, Man Tang, Weiqin ZhangAbstract
Objectives
This study analyzes clinical features and placental pathology of pregnant women infected with SARS-CoV-2 Omicron variants and conducts a two-year follow-up to assess childbirth risks and newborn health outcomes.
Methods
Retrospective analysis of 46 Omicron-infected pregnant women (Omicron group) and 96 uninfected pregnant women (Control group).
Results
Omicron group exhibited higher risk of fetal distress rate, lower leukocyte and lymphocyte counts, and higher C-reactive protein levels compared to the control group. Most infected women (93.48 %) were symptomatic, with fever being the most common symptom. Histologically, acute maternal and fetal inflammatory response were observed in 28.26 and 8.70 % of the Omicron group, but no significant difference from the control group. Maternal vascular malperfusion (50.00 %) and fetal vascular malperfusion (4.34 %) were present in the Omicron group at rates comparable to the controls. Among the 39.13 % of newborns tested for SARS-CoV-2 within three days of birth, 33.33 % tseted positive. Of these positive neonates, 83.33 % were symptomatic, universally presenting with fever, and one developed pneumonia.
Conclusions
Placental pathological findings were non-specific to the Omicron variant. Notably, the two-year follow-up indicated that neither the Omicron-infected mothers nor their newborns experienced long-term adverse health outcomes.