Third-generation oral contraceptives: how risky?

Lancet. 1995 Dec 16;346(8990):1570. doi: 10.1016/s0140-6736(95)91921-x.

Abstract

PIP: Several studies suggest an association between the use of third-generation oral contraceptives (OCs) containing either desogestrel or gestodene and an increased risk of venous thromboembolism. Current users of third-generation OCs faced about a two-fold increased risk of thromboembolism than users of other OCs, even after researchers controlled for possible confounding factors that increase the risk for thromboembolism, e.g., smoking. These latest findings suggest that these OCs actually induce the increased risk of thromboembolism. One study showed that body mass index did not account for the added risk of thromboembolism to users of third-generation OCs. Another study found that family history of venous thrombosis did not increase the risk in third-generation OC users. It did find that nulligravidity and the factor V Leiden mutation contributed to the increased risk of venous thromboembolism in third-generation OC users. Health professionals should consider the size of both risks and benefits linked to various OCs when advising women to discontinue or not to begin using third-generation OCs. The increased risk of venous thromboembolism linked to a third generation OC, beyond that linked to the use of an earlier OC, is 10-15/100,000 woman-years of use. Assuming a typical case fatality rate of around 1%, the increased rate of fatal thromboembolism would range from 1 to 1.5/million woman-years. One study found that mortality from vascular diseases among current users of third-generation OCs is essentially the same as that of users of other OCs. No studies have examined any possible benefits from third-generation OC use in terms of incidence and mortality related to myocardial infarction or diabetes mellitus. Women and their health providers need to make their decision by weighing an increase, albeit small, in thromboembolism-related death against a possible decrease in the risk of other serious conditions.

Publication types

  • Comment

MeSH terms

  • Contraceptives, Oral / adverse effects*
  • Desogestrel / adverse effects
  • Female
  • Humans
  • Norpregnenes / adverse effects
  • Risk Factors
  • Thromboembolism / chemically induced

Substances

  • Contraceptives, Oral
  • Norpregnenes
  • Gestodene
  • Desogestrel