Effect of omicron infection on maternal and neonatal delivery outcomes: A retrospective cohort study

Background: People are very concerned about the adverse effects of Omicron infection on delivery modes, duration of labor, and the postpartum status of pregnant women and neonates. Methods: 382 pregnant women (Omicron group: 136 cases; non-Omicron group: 246 cases) giving birth in our hospital were collected, demographic characteristics, vaccination, clinical manifestation and medication, delivery outcomes of pregnant women and neonates were recorded. Delivery outcomes were compared between the Omicron and non-Omicron groups, acute infection and non-acute infection groups to explore the relationship between adverse delivery outcomes and Omicron infection. Results: Pregnant women in the Omicron group had a longer hospitalization time (6.3 ± 3.6 days vs.5.5 ± 2.3 days), more 2-hour postpartum hemorrhage (291.7 ± 104.9 mL vs.262.7 ± 91.2 mL) and higher neonatal-pediatric transfer rate (20.6 % vs. 2.8 %), which might be associated with fetal distress, prenatal fever and pneumonia/respiratory distress. Neonates transferred to pediatrics due to jaundice were unique in the Omicron group. Fever-pregnant women have a more prolonged second stage of labor and hospital stay while coughing or expectoration ones have a shorter third stage of labor. Delivery outcomes did not differ whether the infected pregnant women were in the acute phase and whether to use antipyretics. Conclusion: Omicron infection can increase the 2-hour postpartum hemorrhage volume and the neonatal-pediatric transfer rate. The symptoms can affect the duration of labor and hospital stay. However, whether the infected pregnant women are in the acute phase or use antipyretics do not affect the delivery outcome.