1. Department of Gynecology, Yidu Central Hospital of Weifang, Qingzhou, Shandong 262500, China
2. Department of Obstetrics, Yidu Central Hospital of Weifang, Qingzhou, Shandong 262500, China
3. Department of Obstetrics, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261031, Iran
4. Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran