876
Participants
Start Date
October 15, 2020
Primary Completion Date
May 23, 2024
Study Completion Date
January 27, 2025
vitamin D
4000IU per day
Placebo
The same doses with vitamin D
Peking University Third Hospital, Beijing
Women's Hospital, Zhejiang University School of Medicine, Hangzhou
Women's Hospital School Of Medicine Zhejiang University
OTHER