1. Department of Obstetrics and Gynaecology; Queen Mary Hospital; The University of Hong Kong; Pokfulam Hong Kong
2. Department of Obstetrics and Gynaecology; Princess Margaret Hospital; Lai Chi Kok Hong Kong
3. Department of Medicine; Queen Mary Hospital; The University of Hong Kong; Pokfulam Hong Kong
4. Department of Pathology; Queen Mary Hospital; The University of Hong Kong; Pokfulam Hong Kong
5. Department of Pathology; Queen Elizabeth Hospital; Ho Man Tin Hong Kong