1. Department of Frigidzone Medicine College of High Altitude Military Medicine Army Medical University (Third Military Medical University) Chongqing 400038 China
2. Key Laboratory of Extreme Environmental Medicine Ministry of Education of China Chongqing 400038 China
3. Key Laboratory of high altitude Medicine People's Liberation Army Chongqing 400038 China
4. Department of Obstetrics and Gynecology Shengjing Hospital of China Medical University Shenyang 110004 China
5. Department of Clinical Epidemiology Shengjing Hospital of China Medical University Shenyang 110004 China
6. Clinical Research Center Shengjing Hospital of China Medical University Shenyang 110004 China
7. NHC Key Laboratory of Advanced Reproductive Medicine and Fertility (China Medical University), National Health Commission Shenyang 110004 China