Department of Obstetrics and Gynecology, Ningbo First Hospital, Ningbo, Zhejiang, China
FengXiang Yao
Department of Obstetrics and Gynecology, Ningbo First Hospital, Ningbo, Zhejiang, China
ShengKun Zhang
Corresponding author. Department of Obstetrics and Gynecology, Xuzhou Central Hospital, 199 Jiefang South Road, Xuzhou, Jiangsu, 221009, China.; Department of Obstetrics and Gynecology, Xuzhou Central Hospital, Xuzhou, Jiangsu, China
