Read the oral contraceptives entry in DynaMed Plus to see summary of evidence on risk of VTE associated with use of oral contraceptives.
Go to adverse effects section of the oral contraceptives entry and scroll down to section on VTE.
Summarizes meta-analysis of cohort and case control studies comparing risk associated with third generation versus second generation OCPs. Adjusted odds ratio 1.7 for VTE in third generation OCPs compared to second generation OCPs.
Also presents the following case-control study of patients with VTE:
van Hylckama Vlieg A, et al. The venous thrombotic risk of oral contraceptives, effects of oestrogen dose and progestogen type: results of the MEGA case-control study. BMJ. 2009 Aug 13;339:b2921. doi:10.1136/bmj.b2921.
1,524 cases (from large population study of VTE risk factors) compared to 1760 controls;baseline characteristics can be seen in Table 1; Tables 2-6 present findings for absolute risk associated with age, different types of progestogen, doses of ethinylestradiol, and duration of use.