Fig. 1. Study cohort. First positive test result (molecular or antigen) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); coronavirus disease 2019 (COVID-19) classification based on data through delivery hospitalization. *Respiratory failure is use of any of the following: extracorporeal membrane oxygenation, continuous positive airway pressure, bi-level positive airway pressure, ventilation. ^†Multiple organ dysfunction or failure is two or more of the following: cardiac arrest, impaired liver function, renal insufficiency (serum creatinine greater than 1.10 mg/dL), renal failure requiring dialysis, encephalopathy, any need for pressor support, thrombocytopenia (platelets less than 100,000). ^‡Other symptoms include fever, cough, sore throat, fatigue, muscle pain, chills, back pain, nausea, vomiting, joint pain, nasal stuffiness, conjunctivitis, confusion, loss of smell or taste, diarrhea, or other. MFMU, Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units.

Metz. COVID-19 Severity and Perinatal Outcomes. Obstet Gynecol 2021.