Session 15 a multifocus on contraception

Abstract

The main objective in oral contraceptive research of the last 35 years has been improvement of safety. Early reports on an association between oestrogens in oral contraceptives and thromboembolic events initiated a continuous decrease in oestrogen dose. Other epidemiological studies reported on the relationship between oral contraceptives with progestogens with a relatively high intrinsic androgenic activity and ischaemic vascular disease. New progestogens were developed with reduced androgenic activity. In combination with ethinylestradiol these more selective progestogens were found to affect lipid variables favorably in view of atherosclerotic disease risk. In addition, the properties of the first of these progestogens, desogestrel, allowed a further oestrogen dose reduction to 20/zg. Subsequent to these developments, which have overcome most safety concerns about oral contraceptives, the latest theme in contraceptive research involves the development of a range of contraceptive methods to meet the needs of individual users. A new combiphasic oral contraceptive regimen, which offers an alternative for women experiencing irregular bleeding on other low dose oral contraceptives, provides an extension to the existing range of pills. In addition, a desogestrel-only pill is being developed for a specific subgroup of women who are not suited to use oestrogens. A third important subgroup concerns women who are not compliant to daily pill-intake. For those women delivery systems with continuous release of low amounts of sex steroids might be an alternative. A subdermal implant and a vaginal ring based on the selective progestogen desogestrel illustrate the ongoing search for innovative contraceptive methods, which are tailored to the specific needs of women.