1 Department of Obstetrics, Baoan Maternal and Child Health Hospital, Jinan University, Shenzhen, China; Clinic for Gynecology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin 12203, Germany.
2 Department of Joint Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
3 Department of Obstetrics, Baoan Maternal and Child Health Hospital, Jinan University, Shenzhen, China.
4 Department of Obstetrics, Baoan Maternal and Child Health Hospital, Jinan University, Shenzhen, China. Electronic address: zhuyuanfang111@163.com.