Amenorrhea rates during the first year of levonorgestrel 52 mg intrauterine system (IUS) use are similar at 9 and 12 months, a recent study showed, with amenorrhea at 12 months most common among women with shorter baseline duration of menstrual flow. The cohort analysis included 1,714 nulliparous and parous women who received a Liletta levonorgestrel 52 mg IUS in a multicenter trial to evaluate efficacy and safety for up to 8 years. Researchers assessed bleeding patterns in 90-day intervals, with amenorrhea defined as no bleeding or spotting in the preceding 90 days.
- Prior users averaged 50±19 months of use before IUS placement; 38.4% of these women reported amenorrhea at 12 months.
- Amenorrhea rates for non-prior users at 3, 6, 9, and 12 months were 0.2%, 9.1%, 17.2%, and 16.9%, respectively.
- The only significant predictor of amenorrhea at 12 months was self-reported baseline duration of menstrual flow of <7 days vs ≥7 days (18.2% vs 5.2%, aOR 3.70).
Darney PD, Stuart GS, Thomas MA, Cwiak C, Olariu A, Creinin MD. Amenorrhea rates and predictors during one year of levonorgestrel 52 mg intrauterine system use. [Published online ahead of print October 13, 2017]. Contraception. doi:10.1016/j.contraception.2017.10.005.