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The frameless copper IUD (GyneFix) and the TCu380A IUD: results of an 8-year multicenter randomized comparative trial
Olav Meirik1, Patrick J Rowe, Alexandre Peregoudov
1UNDP/UNFPA/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction, 1211 Geneva 27, Switzerland. meiriko@icmer.org
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.
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