1. Liang, R., Ye, R., Li, H., Ren, A., & Liu, J. (2010). Study on the current status of spontaneous abortion of primigravid women in Jiaxing of Zhejiang province, China. Chinese Journal of Epidemiology, 31(7), 755–758.
2. Avant, R. F. (1983). Spontaneous abortion and ectopic pregnancy. Primary Care, 10(2), 161–172.
3. Mcbride, W. Z. (1991). Spontaneous abortion. American Family Physician, 43(1), 175–182.
4. Xie, X., Gou, W. L. (2013). Obstetrics and Gynecology, 8th ed. Beijing, China: People’s Medical Publishing House, pp. 47–49, ISBN 978–71–1717–180–9.
5. Xiaobin, Hu., Miao, M., Bai, Y., Cheng, N., & Ren, X. (2018). Reproductive factors and risk of spontaneous abortion in the Jinchang cohort. International Journal of Environmental Research and Public Health, 15, 2444.