1. State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
2. Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, China
3. Department of Gynaecology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
4. Department of Obstetrics and Gynaecology, Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa