State-of-the-art of non-hormonal methods of contraception: III. Intrauterine devices

Since the 1959 revival of the IUD, non-hormonal devices have become the most widely used of all reversible contraceptives. Pregnancy rates of copper-releasing IUDs in current use range from approximately 0.5 to 1.5 per hundred continuing users in the first year, with somewhat lower annual pregnancy rates thereafter. Evidence-based research has been systematically conducted and translated into guidelines for eligibility criteria and problem management. Recent device research, beyond the T, Multiload and frameless devices has centred on improved designs such as U ,Y and Slimline shapes, or enhanced copper release, the latter through electrochemical effects or nanotechnology applications. Other IUD research foci concern devices that decrease bleeding and pain by releasing non-steroidal anti-inflammatory drugs. Yet other research lines indicate noncontraceptive benefits of copper intrauterine devices in protecting against endometrial cancer, and favourable risk-benefit analyses of IUD use by women at risk of or post HIV infection. IUD mechanisms of action and the relation of IUDs to pelvic infection and ectopic pregnancy are briefly reviewed. For our literature search we used Medline, Popline and Cochrane Library data bases, Google search, our personal files, and the references contained in articles in our files.