The Cu-Safe 300 is one of the latest additions to the array of available IUDs. It was specifically designed to decrease unwanted side-effects (e.g. bleeding, pain and expulsion) while providing simplicity of insertion, ease of removal and fair contraceptive protection. For comparison, the TCu380A was chosen. Both types were inserted at random in 600 recipients by a group of independent physicians with a long standing experience in intrauterine contraception. Life table analysis was used for comparison over a period of three years. The Cu-Safe 300 produced a slightly but not statistically significant higher pregnancy rate and more expulsions. Removals for bleeding and pain, however, were significantly less frequent. All inserting physicians agreed that insertion and removal of this new device was remarkably easy.