1. Department of Gynecological Nursing, West China Second University Hospital, Sichuan University/West China School of Nursing, Chengdu, China.
2. Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China.
3. Department of Nursing, West China Second University Hospital, Sichuan University/West China School of Nursing, Chengdu, China.