| Affiliation: | 1. Department of Obstetrics and Gynecology, Princess Margaret Hospital, Hong Kong;2. Prenatal Diagnostic Laboratory, Tsan Yuk Hospital and Department of Obstetrics and Gynecology, Queen Mary Hospital, Hong Kong;3. Department of Obstetrics and Gynecology, Tuen Mun Hospital, Hong Kong;4. Department of Obstetrics and Gynecology, United Christian Hospital, Hong Kong;5. Department of Obstetrics and Gynecology, Queen Elizabeth Hospital, Hong Kong;6. Department of Obstetrics and Gynecology, Pamela Youde Nethersole Easten Hospital, Hong Kong |
