1 Department of Obstetrics and Gynecology, The People's Hospital of China Three Gorges University. The First People's Hospital of Yichang, Jiefang Road 4, Yichang City, 443003, Hubei Province, People's Republic of China. 563747475@qq.com.
2 Department of Ultrasound Imaging, The People's Hospital of China Three Gorges University. The First People's Hospital of Yichang, Yichang City, Hubei Province, People's Republic of China.