Thromboembolism with oral contraceptives

Cyproterone acetate in combination with ethinylestra-diol is indicated for the treatment of women with severe acne and moderately severe hirsutism. This product has been associated with a greater risk of venous thromboembolism than oral contraceptives. However, in a rigorous case-control study the risk of venous thromboembolism with cyproterone acetate + ethinylestradiol was not significantly greater than the risk in women who took conventional oral contraceptives (25). 

Much of the evidence on the occurrence of thromboembolic complications with oral contraceptives or hormone replacement therapy has been gathered from European or American populations, and it can be helpful to identify data from other parts of the world, where factors such as... 

A 5-year case-control study involving all Danish hospitals has once more quantified the thromboembolic risks associated with oral contraceptives as a whole the risk with third-generation products was some 30% higher than with second-generation products (RR = 1.3 Cl = 1.0, 1.8) (123). However, data on cerebral thrombosis from the same study showed that with third-generation products the mean risk was some 40% lower than with second-generation products (RR = 0.6 Cl = 0.4, 0.9) (124). 

Stroke is a very uncommon event in childbearing women, occurring in approximately 11 per 100,000 women over a 1-year period of time. Therefore, even a doubling of this risk with oral contraceptive pills would have minimal effect on attributable risk. The estimated risk of myocardial infarction associated with oral contraceptive pill use in nonsmokers is 3 per million women over 1 year. The estimated risk of venous thromboembolism attributable to oral contraceptive pills is less than 3 per 10,000 women per year. However, the risk may be increased in women who smoke or have other predisposing factors to thrombosis or thromboembolism. In fact, it should be emphasized that the risk of serious cardiovascular side effects is particularly marked in women over 35 years of age who are heavy smokers (e.g., more than 15 cigarettes per day). Additionally, the literature suggests that there may be an increased risk of breast cancer associated with long-term oral contraceptive pill use in women under the age of 35. However, because the incidence of breast cancer is so relatively low in this population, the attributable risk of breast cancer from birth control pill use is small. 

To put it simply, this work further delineated the nature of the thromboembolic risk associated with oral contraceptives as a whole, defined more clearly the susceptible groups, and also underlined the particular problem attached to products of the third generation. 

The relationship between oral contraceptive usage and thromboembolism is still being questioned (83 ). However, the epidemiological studies by the case-control method consistently show an increased relative risk associated with oral contraceptive use in women with no predisposing diseases. 

There is an increased risk of post-operative thromboembolic complications in women taking oral contraceptives Ifposs-bte, use of the drug is discontinued at least 4 weeks before a surgical procedure associated with thromboembolism or during prolonged immobilization. 

Adverse effects include nausea, weight gain, breast tenderness, and breakthrough bleeding. Oral contraceptives have also been associated with an increased incidence of thromboembolic disease, particularly in women who use tobacco products or have other risk factors for thromboembolism. The development of these complications is significantly reduced when low-dose estrogen formulations of oral contraceptives are used.3... 

Cilest contains ethinylestradiol and norgestimate whereas Yasmin contains ethinylestradiol in combination with drospirenone. Both are combined oral contraceptives available as tablets, which have to be taken once daily for 21 days. Both are contraindicated in patients with venous thromboembolic diseases. 

Current estimates are that oral contraceptive use doubles to triples the overall risk of thromboembolic disease. The increased use in recent years of oral contraceptives with lower estrogen content probably contributes to the decreased risk. However, the risk is... 

By 1980 it was considered clear that the risk of thromboembolic events was further increased under particular conditions. It was higher in smokers, in older women, and in the obese, and appropriate warnings were issued. The fact that these warnings to a large extent eliminated the high-risk individuals who had formed part of the early population of oral contraceptive users means that data from the early period cannot be used to provide a valid historical comparison with later findings (42,43). 

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