Patients
This retrospective study included pregnant women from East District of People’s Hospital of Wuhan University (Wuhan, China). All pregnant women who were diagnosed with COVID-19 according to WHO interim guidance between Feb 1, 2020 and Mar 20, 2020 were screened in our study. We classified the women into two groups, namely early and middle pregnancy (1-27 weeks of gestation) and late pregnancy (≥28 weeks of gestation). Ethics approval was granted by the ethics board of the Institute of People’s Hospital of Wuhan University (WDRY2020-K068). Informed consent was waived in view of the retrospective nature of the study.