1. Departments of Obstetrics and Gynecology, Stanford University School of Medicine, California
2. Maternal and Children's Health Hospital of Shenzhen City, Shenzhen, People's Republic of China
3. Department of Obstetrics and Gynecology, College of Medicine, Hanyang University, Seoul, Korea
4. Department of Urology, Stanford University School of Medicine, California
5. College of Engineering, Nihon University, Fukushima, Japan