Interval iud insertion in parous women: a randomized multicentre comparative trial of the Lippes Loop D, TCu220c and the Copper 7.

A multicentre randomized clinical trial of the TCu220C, Lippes Loop D and Copper 7 was undertaken in nine WHO Collaborating centres for Clinical Research in Human Reproduction. A total of 984, 992 and 994 devices, respectively, were inserted between 1976 and 1978. The subjects were followed for two years. At this time 18,743, 17,013 and 17,927 woman-months experience had been accumulated with each device, respectively. The Lippes Loop consistently failed to perform as well as the TCu220C regardless of age or parity. The TCu220C had statistically significantly lower pregnancy rates at one and two years of use than either of the other two devices as well as lower expulsion rates. The TCu220C had lower removal rates at one and two years than the Lippes Loop and Copper 7. At one and two years the TCu220C had significantly higher continuation rates than the other two devices. It is concluded that the TCu220C is the device of choice amongst the three devices studied.