Affiliation: | 1. Department of Obstetrics and Gynaecology, Shandong Provincial Qianfoshan Hospital, Jinan, People''s Republic of China;2. Minimally Invasive Surgery, Baylor College of Medicine, Houston, Texas;3. Division of Reproductive Medicine, Jinan Central Hospital Group, Jinan City, People''s Republic of China;4. Guangzhou Medical University, Guangzhou, People''s Republic of China |