PT - JOURNAL ARTICLE ED - , TI - Intrauterine devices now AID - 10.1136/dtb.20.18.69 DP - 1982 Sep 03 TA - Drug and Therapeutics Bulletin PG - 69--72 VI - 20 IP - 18 4099 - http://dtb.bmj.com/content/20/18/69.short 4100 - http://dtb.bmj.com/content/20/18/69.full SO - Drug Ther Bull1982 Sep 03; 20 AB - Changes and refinements in the structure of intrauterine devices (IUDs) continue to be made. Have they improved contraceptive efficacy or reduced unwanted effects?