Aim: The development of the 'frameless' intrauterine system (IUS) is a response to the growing need to develop high-performing, long-acting, reversible, and acceptable contraceptives with a high continuation of use.
Methods: This is a review of 15 years of clinical experience in randomized controlled and non-randomized clinical trials.
Results: The IUS has a similar failure rate as the TCu380A Intrauterine device (IUD), considered the 'golden standard' IUD, which is attributed to the optimal target delivery of the copper ions in the upper part of the uterine cavity. Its performance is further optimized by the atraumatic design, which reduces partial and total expulsion and minimizes the side-effects and discomforts experienced with conventional 'framed' IUDs. The mini IUS is likely to further reduce the menstrual blood loss due to the very small size. The safety of the anchoring concept is beyond doubt as was demonstrated in all clinical studies covering 15,000 woman-years experience.
Conclusions: Young nulliparous/nulligravid and parous women may significantly benefit from the advantages the 'frameless' IUS, which could be strategically important to help in reducing the increasing number of unintended pregnancies and induced abortions worldwide. Furthermore, the 'frameless' IUS has been shown to be highly effective for emergency contraception and for immediate postabortal insertion. The long lifespan of the IUS could constitute a cost-effective reversible alternative to irreversible female sterilization.