1Hui C, Lili M, Libin C, et al. Changes in coagulation and hemody- namics during pregnancy:a prospective longitudinal study of 58 ea- ses [ J ]. Arch Gynecol Obstet,2012,285 : 1231 ~ 1236.
2Sitruk Ware R. Nath A. Metabolic efects of contraceptive steroids [J]. Rev Endocr Metab Disord,2011,12(2) :63 -75.
3Van Hylckama lieg A, Helmerhorst FM, Vandenbroucke JP, et al. The venous thrombotic risk of oral contraceptives, effects of oestro- gen dose and progestogen type: results of the MEGA case ~ control study [J]. BMJ,2009,33(9) :b2921.