Clinical characteristics of pregnant women with COVID‑19 in Japan from a nationwide questionnaire survey

BACKGROUND: We examined the clinical characteristics and outcomes of pregnant women with COVID‑19 on a national scale in Japan. METHODS: A nationwide questionnaire-based survey for all maternity services in Japan by the Japan Association of Obstetricians and Gynaecologists was conducted in July 2020 and July 2021, respectively. Information regarding maternal characteristics and epidemiological, clinical, treatment, and perinatal outcomes of pregnant women with COVID-19 during the first wave and second to fourth wave were collected. RESULTS: Responses from 1,418 and 1,288 institutions were assessed (65% and 60% of all delivery institutions in Japan.) Seventy-two and 1,474 pregnant women with COVID-19 were reported in the first wave and second to fourth wave, respectively. The most common route of infection was familial. Of the all patients, 80% were symptomatic, 7% had severe respiratory symptoms and one died (a tourist). The third trimester of pregnancy was the most common timing of diagnosis and severe cases were frequently reported in late pregnancy compared with in early pregnancy. Most pregnant women with COVID-19 had a cesarean section if delivery was necessary. In severe cases, preterm delivery due to infection was also common. There were no SARS-CoV-2 transmissions to newborns. CONCLUSIONS: The importance of infection prevention should be emphasized, especially in women in late pregnancy, their families, and any cohabitants. The pregnant women in late pregnancy with COVID-19 need careful observation and follow-up.