The need for O2 in pregnant and postpartum women with COVID-19 is associated with clinical factors (advanced age, obesity, hypertension, smoking), symptoms (dyspnea, cough, fever, asthenia, fatigue, and odynophagia), physical and laboratory examination and tests of images on admission (respiratory rate ≥ to 24 breaths per minute, O2 saturation < 95%, ground-glass CT, hemoglobin values < 11 mg/dL, lymphocytes < 1.50 mil/mm3 and C-Reactive Protein [CPR] levels > 21 mg/L). This evidence concerns the gene CRP and COVID-19.