Abstract Objectives: To determine the incidence and risk of adverse obstetric and neonatal outcomes according to SARS-CoV-2 infection severity in pregnant women. Method: Open prospective study of pregnant women tested for SARS-CoV-2 by serological and molecular assays during pregnancy or delivery in two hospitals in Sao Paulo, Brazil from April 12, 2020, to February 28, 2021. Five groups were considered for analysis: C0, negative COVID-19 results and no COVID-19 symptoms; C1, positive COVID-19 results, and no symptoms; C2, positive COVID-19 results with mild symptoms; C3, positive COVID-19 results with moderate symptoms; and C4, positive COVID-19 results with severe symptoms. The association between obstetric and neonatal outcomes and COVID-19 severity was determined using multivariate analysis. Results: 734 eligible pregnant women were enrolled as follows: C0 (n = 357), C1 (n = 127), C2 (n = 174), C3 (n = 37), and C4 (n = 39). The following pregnancy and neonatal outcomes were associated with severe COVID-19: oligohydramnios (adjusted Odds Ratio [aOR] = 6.18; 95% CI 1.87‒20.39), fetal distress (aOR = 4.01; 95% Confidence Interval [CI] 1.84‒8.75), preterm birth (aOR = 5.51; 95% CI 1.47‒20.61), longer hospital stay (aOR = 1.66; 95% CI 1.36‒2.02), and admission to the neonatal intensive care unit (aOR = 19.36; 95% CI, 5.86‒63.99). All maternal (n = 6, 15.4%, p < 0.001) and neonatal (n = 5, 12.5%, p < 0.001) deaths and most fetal deaths (n = 4, 9.8%, p < 0.001) occurred in C4 group. Moderate COVID-19 was associated with oligohydramnios (aOR = 6.23; 95% CI 1.93‒20.13) and preterm birth (aOR = 3.60; 95% CI 1.45‒9.27). Mild COVID-19 was associated with oligohydramnios (aOR=3.77; 95% CI 1.56‒9.07). Conclusion: Adverse pregnancy and neonatal outcomes were associated with maternal symptomatic COVID-19 status, and risk increased with disease severity. HIGHLIGHTS COVID-19 increases the rates of adverse pregnancy and neonatal outcomes. Serious cases are associated with oligohydramnios, fetal distress, prematurity, neonatal ICU admission, maternal and neonatal deaths. The maternal clinical status dictates obstetric and neonatal outcomes.

Abstract Objective: To identify risk factors for Oxygen (O2) needs in pregnant and postpartum women with COVID-19. Methods: Prospective cohort involving pregnant women hospitalized with COVID-19 from April to October 2020. The oxygen need was analyzed regarding risk factors: demographic characteristics, clinical and laboratory parameters at hospital admission, and chest Computer Tomography (CT) findings. Poisson univariate analysis was used to estimate the Relative Risk (RR) and 95% Confidence Intervals. Results: 145 patients, 80 who used and 65 who did not use O2, were included. Body mass index ≥ 30, smoking, and chronic hypertension increased the risk of O2 need by 1.86 (95% CI 1.10–3.21), 1.57 (95% CI 1.16‒2.12), and 1.46 (95% CI 1.09‒1.95), respectively. Patients who were hospitalized for COVID-19 and for obstetric reasons had 8.24 (95% CI 2.8‒24.29) and 3.44 (95% CI 1.05‒11.31) times more use of O2 than those admitted for childbirth and abortion. Respiratory rate ≥ 24 breaths/min and O2 saturation < 95% presented RR for O2 requirements of 2.55 (1.82‒3.56) and 1.68 (95% CI 1.27-2.20), respectively. Ground Glass (GG) < 50% and with GG ≥ 50%, the risk of O2 use were respectively 3.41-fold and 5.33-fold higher than in patients who haven’t viral pneumonia on CT. The combination of C-reactive protein ≥ 21 mg/L, hemoglobin < 11.0 g/dL, and lymphopenia < 1500 mm3 on hospital admission increased the risk of O2 use by 4.97-times. Conclusions: In obstetric patients, clinical history, laboratory, clinical and radiological parameters at admission were identified as a risk for O2 need, selecting the population with the greatest chance of worsening. HIGHLIGHTS In unvaccinated pregnant and postpartum women, any need for oxygen supply increases the risk of invasive ventilation. Obesity, smoking and chronic arterial hypertension proved to be risk factors for the use of oxygen in pregnant and postpartum women with COVID-19. The combination of C-reactive protein ≥ 21 mg/L, hemoglobin < 11.0 g/dL, and lymphopenia < 1500 mm on hospital admission and the presence of ground glass ≥ 50% in computer tomography increased the risk of O2 use by 4.97 and 5.33 times respectively in pregnant and postpartum women with COVID-19.