Among 57 hospitalized patients with SARS-CoV-2 infection who underwent vaginal or cesarean delivery, 7 had spontaneous preterm or respiratory-indicated preterm delivery, a rate of 12%, according to a study published in Obstetrics & Gynecology. For comparison, 7% of patients had preterm delivery in 2019, researchers reported “We also noted a high cesarean delivery rate in the study population (39% vs. 27% in the same area in 2019), mainly as a result of maternal respiratory-indicated urgent delivery,” wrote Valeria M. Savasi, MD, PhD, of the University of Milan and Luigi Sacco Hospital, also in Milan, and colleagues.
Data do not indicate that pregnant women are more susceptible to severe COVID-19 infection, nor have studies suggested an increased risk of miscarriage, congenital anomalies, or early pregnancy loss in pregnant patients with COVID-19, the authors wrote. Studies have described an increased risk of preterm birth, however.
To study clinical features of maternal SARS-CoV-2 infection and potential factors associated with severe disease and iatrogenic delivery, Dr. Savasi and colleagues conducted a prospective study of 77 women with laboratory-confirmed SARS-CoV-2 infection who were admitted during pregnancy or the immediate postpartum period in 12 maternity hospitals in northern Italy between Feb. 23 and March 28, 2020.
The investigators classified patients as having severe disease if they underwent urgent delivery based on maternal respiratory function or if they were admitted to an ICU or subintensive care department. In all, 14 patients (18%) were classified as having severe disease.
“Three patients were intubated after emergency cesarean delivery performed for maternal deterioration, and one patient underwent extracorporeal membrane oxygenation,” Dr. Savasi and colleagues reported. The results are consistent with epidemiologic data in the nonpregnant population with COVID-19 disease.
Of 11 patients with severe disease who underwent urgent delivery for respiratory compromise, 6 had significant postpartum improvement in clinical conditions. No maternal deaths occurred.
“Increased BMI [body mass index] was a significant risk factor for severe disease,” Dr. Savasi and colleagues wrote. “Fever and dyspnea on admission were symptoms significantly associated with subsequent severe maternal respiratory deterioration.”
Most patients (65%) were admitted during the third trimester, and 20 patients were still pregnant at discharge.
“Nine newborns were admitted to the neonatal intensive care unit,” the authors wrote. “Interestingly, besides prematurity, fetal oxygenation and well-being at delivery were not apparently affected by the maternal acute conditions.” Three newborns with vaginal delivery and one with cesarean delivery tested positive for SARS-CoV-2. The newborns may have been infected after delivery, Dr. Savasi and colleagues added. For all newborns, rooming-in and breastfeeding were performed, and none developed respiratory symptoms.
Criteria for hospital admission and therapeutic protocols may have varied between hospitals, the authors noted. In addition, the study included 12 patients who were asymptomatic and admitted for obstetric indications. These patients were tested for SARS-CoV-2 because of contact with an infected individual. Most patients were symptomatic, however, which explains the high rate of maternal severe outcomes. Hospitals have since adopted a universal SARS-CoV-2 screening policy for hospitalized pregnant patients.
Kristina Adams Waldorf, MD, professor of obstetrics and gynecology at the University of Washington, Seattle, commented in an interview that Savasi et al. describe one of the larger COVID-19 in pregnancy cohorts to date with rates of severe disease and delivery for respiratory compromise, which is remarkably similar to Washington state (severe disease, 18% vs. nearly 15%; delivery for respiratory compromise, 16% vs. 20%). As in Washington state, Italian women with a higher prepregnancy BMI were overrepresented in the severe disease group.
“Data are beginning to emerge that identify women who were overweight or obese prior to pregnancy as a high risk group for developing severe COVID-19. These data are similar to known associations between obesity and critical illness in pregnancy during the 2009 ‘swine flu’ (influenza A virus, H1N1) pandemic,” she said.
“This study and others indicate that the late second and third trimesters may be a time when women are more likely to be symptomatic from COVID-19. It remains unclear if women in the first trimester are protected from severe COVID-19 outcomes or have outcomes similar to nonpregnant women,” concluded Dr. Waldorf.
One study author disclosed receiving funds from Lo Li Pharma and Zambongroup. The other authors did not report any potential conflicts of interest. Dr. Waldorf said she had no relevant financial disclosures.
SOURCE: Savasi VM et al. Obstet Gynecol. 2020 May 19. doi: 10.1097/AOG.0000000000003979.