Slow train gathers speed

Abstract

The otherwise slow pace of contraceptive research developments has recently quickened, with new products developed, more on the way, and encouraging new data emerging about existing methods. While the 1995 UK pill scare called attention to a differential in the risk of venous thromboembolism (VTE) between pills containing levonorgestrel or norethisterone and those containing desogestrel or gestodene, there is only an extremely small level of excess mortality attributable to third-generation progestogens, less than 2 per million women per year. Tentative evidence suggests that pills with less anti-estrogenic progestogens are neutral with regard to coronary artery disease. The pill remains extremely safe for healthy young women, although additional research with larger numbers of participants is warranted. Salient research findings are that the combined oral contraceptive pill may protect against colon cancer, the pill appears to offer no protection against bone fractures, new products contain less estrogen and have a shortened pill-free interval, a WHO paper showed no significant association between cardiovascular disease and the use of oral or injectable progestogens, a UK study showed no correlation between bone density and plasma estrogen concentrations among long-term users of depot medroxyprogesterone acetate, and a WHO controlled trial found a progestogen-only method of emergency contraception to be considerably more effective in preventing expected pregnancies than the Yuzpe regimen. The T 380 copper IUD provides very high protection against intrauterine and extrauterine pregnancies for 10 years and is now available in an improved inserting mechanism, the Mirena levonorgestrel-releasing IUD system is now licensed for 5 years, and the GyneFIX IUD implant is a frameless device fixed during insertion to the fundal myometrium.