1. School of Nursing; College of Medicine; Chang Gung University; Tao-Yuan Taiwan
2. Department of Obstetrics and Gynecology; College of Medicine; Chang Gung University; Tao-Yuan Taiwan
3. Department of Obstetrics and Gynecology; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
4. School of Nursing; University of Maryland at Baltimore; Baltimore MD USA