1 Department of Gynecology, Center for Reproductive Medicine (Drs Wang, Tian, Liu, He and Wang), Zhejiang Provincial People's Hospital.
2 Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital (Dr. Lin), Zhejiang University, Hangzhou, China.
3 Department of Gynecology, Center for Reproductive Medicine (Drs Wang, Tian, Liu, He and Wang), Zhejiang Provincial People's Hospital. Electronic address: wangyanpeng@hmc.edu.cn.