Clinical Characteristics and Vertical Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Pregnant Women and Their Neonates in Korea

BACKGROUND: There are limited data on the clinical characteristics and the vertical transmission rate of pregnant women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and their neonates in Korea. MATERIALS AND METHODS: Pregnant women who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were retrospectively reviewed in Asan Medical Center from September 1, 2020, to April 26, 2022. All neonates and infected women underwent a polymerase chain reaction test for severe acute respiratory syndrome corona virus 2 within 24 hours of birth and at 48-hour interval if they stayed in the hospital. RESULTS: A total of 60 pregnant women gave birth by cesarean section (n = 40, 66.7%) or vaginal delivery (n = 20, 33.3%). Among them, 3 women gave birth to twins. Delivery occurred, on average, at 38(+2) weeks (± 2(+0)) of gestational age, and 9 patients (15.0%) had underlying diseases. Of these 60 patients, 9 (15.0%) received coronavirus disease 2019 vaccinations. Pneumonia was confirmed by a chest radiograph in 7 patients (11.7%), and 2 patients (3.3%) required supplemental oxygen therapy, both of whom eventually recovered. The mean birthweight of the neonates was 3,137 g (± 557.6). Further, 8 neonates (12.7%) were of low-birth weight (< 2,500 g), and 11 neonates (17.5%) were preterm (<37 weeks of gestation). Apgar score was median 8 (8 - 9) at 1 minute and 9 (9 – 9.5) at 5 minutes. Four neonates (6.3%) required invasive mechanical ventilation. All neonates had negative SARS-CoV-2 test results. Therefore, there was no vertical transmission in 63 of the neonates (0%, 95% confidence interval [CI]: 0 - 6) CONCLUSION: Pregnant Korean women with SARS-CoV-2-infection had favorable obstetric outcomes, and the risk of vertical transmission to their neonates was low. Managing the infection risks of pregnant women and their neonates during the coronavirus disease 2019 pandemic are required.