The frameless copper IUD (GyneFix) and the TCu380A IUD: results of an 8-year multicenter randomized comparative trial

Background

Clinical performance of the frameless copper IUD (GyneFix), designed to reduce side effects related to the frame of conventional IUDs, and TCu380A was compared.

Study Design

Randomized Multicenter randomized comparative trial. Parous women requesting and eligible to use IUD were admitted in 21 centers in eight countries in 1989-1993 and followed-up for up to 8 years.

Results

Two thousand twenty-seven women were randomized to the frameless IUD and 2036 to TCu380A; 43 insertions of the frameless IUD failed and none for TCu380A. First-year expulsion rate of the frameless IUD was 5.3 (95% CI: 4.4-6.4) per 100 and 2.5 (95% CI: 1.9-3.3) for the TCu380A; second- through eighth-year expulsion rates were not different. First-year pregnancy rates for the frameless IUD and TCu380A were 1.3 (95% CI: 0.9-2.0) and 0.5 (95% CI: 0.3-0.9), respectively; second- through eighth-year cumulative pregnancy rates were 1.2 (95% CI: 0.7-1.9) and 2.5 (95% CI: 1.8-3.4), respectively. The 8-year cumulative rates of ectopic pregnancy and IUD removal for pain were lower for the frameless IUD than for TCu380A. Removals for other reasons were not different.

Conclusions

The frameless IUD had more insertion failures, expulsions and pregnancies in the first year than TCu380A, but fewer pregnancies from the second through the eighth year, and by 8 years had fewer ectopic pregnancies and removals for pain.