Data Collection
Outpatient medical records, laboratory findings and radiological characteristics were reviewed by three obstetricians and gynecologists. Demographic characteristics, clinical manifestations and diagnostics, the results of the COVID-19-associated tests, laboratory findings, treatment, and outcomes were extracted from electronic medical records.
Throat swab samples were collected by professional swab-sampling staff members, and the NAT was performed using real-time reverse transcription-polymerase chain reaction according to the manufacturer’s protocol (DAAN Gene Co., Ltd. Of Sun Yat-sen University). The serological SARS-CoV-2 test kits were performed according to the manufacturer’s instructions (Tangshan Innovita Biological Technology Co., Ltd., 2019-nCoV Ab Test (Colloidal Gold)).