What are the results of the WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception regarding ischemic stroke and combined oral contraceptives?
The WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception found that there is an association between current use of combined oral contraceptives and an increased risk of ischemic stroke. Results of the study, which were published in The Lancet in 1996, showed that the risk of ischemic stroke increased with increasing duration of use and that the risk was highest among women younger than 35 years of age. The study also showed that the risk of ischemic stroke decreased with increasing age and that the risk decreased with time after discontinuation of combined oral contraceptives. 