About the Authors

Na Wei

Affiliation Department of Obstetrics & Gynaecology, Queen Mary Hospital, the University of Hong Kong, Hong Kong, Hong Kong

Stephanie S. Liu

Affiliation Department of Obstetrics & Gynaecology, Queen Mary Hospital, the University of Hong Kong, Hong Kong, Hong Kong

Karen K. L. Chan

Affiliation Department of Obstetrics & Gynaecology, Queen Mary Hospital, the University of Hong Kong, Hong Kong, Hong Kong

Hextan Y. S. Ngan

gyonc@hku.hk

Affiliation Department of Obstetrics & Gynaecology, Queen Mary Hospital, the University of Hong Kong, Hong Kong, Hong Kong

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: NW SSL HYSN. Performed the experiments: NW. Analyzed the data: NW SSL. Contributed reagents/materials/analysis tools: NW SSL KKLC. Wrote the paper: NW SSL KKLC. Gave the final approval of the version to be published: HYSN SSL KKLC.