1. Department of Obstetrics and Gynaecology; Tuen Mun Hospital; Hong Kong SAR China
2. Department of Obstetrics and Gynaecology; Prince of Wales Hospital; Hong Kong SAR China
3. Department of Obstetrics and Gynaecology; Pamela Youde Nethersole Eastern Hospital; Hong Kong SAR China
4. Department of Obstetrics and Gynaecology; United Christian Hospital; Hong Kong SAR China
5. Department of Obstetrics and Gynaecology; Queen Elizabeth Hospital; Hong Kong SAR China
6. Department of Obstetrics and Gynaecology; Princess Margaret Hospital; Hong Kong SAR China
7. Department of Obstetrics and Gynaecology; Queen Mary Hospital; Hong Kong SAR China
8. Department of Obstetrics and Gynaecology; Kwong Wah Hospital; Hong Kong SAR China
9. Clinical Genetic Service, Department of Health; Hong Kong SAR China
10. Departments of Paediatrics and Adolescent Medicine; The University of Hong Kong; Hong Kong SAR China
11. Prenatal Diagnostic and Counselling Division; Tsan Yuk Hospital; Hong Kong SAR China
12. Department of Obstetrics and Gynaecology; The University of Hong Kong; Hong Kong SAR China