1. Department of Minimally Invasive Gynecological Centre, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China (mainland)
2. Department of Perinatal Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China (mainland)
3. Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China (mainland)