Maternal and perinatal outcomes following pre-Delta, Pelta, and Omicron SARS-CoV-2 variants infection among unvaccinated pregnant women in France and Switzerland: a prospective cohort study using the COVI-PREG registry - Favre, G; Maisonneuve, E; Pomar, L (Lancet Reg Health Eur, 2023)
10.1016/j.lanepe.2022.100569