Further Extending Hormonal Intrauterine Device Use

Levonorgestrel intrauterine systems (IUSs) are highly effective in reducing menstrual blood loss and preventing pregnancy. When the Mirena 52 mg levonorgestrel IUS was first approved by the FDA, it was labelled for 5 years of use. To assess the contraceptive efficacy of Liletta, a low-cost levonorgestrel 52 mg IUS, researchers enrolled 1751 women (age range, 16–45) in an ongoing phase III trial with plans for 10 years of follow-up.

Through 6 years' follow-up, 9 pregnancies occurred, yielding a cumulative Pearl Index of 0.18 pregnancies per 100 women-years of use (between years 5 and 6, no additional pregnancies were identified).