Objectives: To describe the clinical and paraclinical characteristics of pregnant women infected with COVID-19 at Hanoi Obstetrics and Gynecology Hospital. Subjects and methods: A retrospective observational cross-sectional study, 1261 pregnant women who were confirmed to be infected with COVID-19 with gestational age of 22 weeks or more were treated at Hanoi Obstetrics and Gynecology Hospital from December 2021 to April 2022. Results and conclusions: The average gestational age at hospital admission was 37.5 ± 3.5 weeks. The percentage of pregnant women who had received at least one dose of the COVID-19 vaccine was 41.6%. The percentage of patients with no symptoms was 29.3%. The most common clinical symptoms were cough (57.3%), nasal congestion (41.2%), and sore throat (40.3%). The laboratory tests showed an increase in D-dimer (100%) and a decrease in lymphocytes – Lymphocytopenia (52.7%). The younger the gestational age, the more severe the COVID-19 infection is. Vaccination against COVID-19 during pregnancy reduces the risk and severity of the disease, with a statistical significance of p<0.011.