Findings support the continued use of 52-mg LNG-IUS for up to 8 years in women wishing to continue treatment.

USA: Findings from the Mirena Extension trial have shown the high contraceptive efficacy, a favorable safety profile, and user satisfaction of 52-mg levonorgestrel-releasing intrauterine system (52-mg LNG-IUS) through 8 years of use. The findings were published in the American Journal of Obstetrics and Gynecology.

A total of 26 post-treatment pregnancies were reported, of which 24 occurred in women who discontinued 52-mg LNG-IUS because of their wish for pregnancy. The bleeding pattern remained highly favorable in women who elected to continue use for eight years.

The 52-mg levonorgestrel-releasing intrauterine system is a long-acting contraceptive option with approval for its use for up to 7 years. The Mirena Extension Trial by Jeffrey T Jensen, Oregon Health & Science University, Portland, Oregon, USA, and colleagues evaluated the safety and efficacy of 52-mg LNG-IUS during extended use beyond 5 and 8 years.

The multicenter, single-arm study in the US enrolled existing users of 52-mg LNG-IUS for 4.5-5 years aged 18-35 years. The researchers assessed the contraceptive efficacy (Pearl Index) and the cumulative failure rate (using the Kaplan-Meier method) of 52-mg LNG-IUS during extended use. Bleeding outcomes and adverse events were also evaluated.

Two hundred forty-three entered, and 223 completed eight years of 52-mg LNG-IUS use out of 362 participants starting Year 6. Just over half the participants were parous. The mean age was 29.2 years, and all participants were ≤36 years at the end of Year 8.

The study demonstrated the following findings:

The researchers conclude, "these findings support the continued use of 52-mg LNG-IUS for up to 8 years in women wishing to continue treatment."

Jensen JT, Lukkari-Lax E, Schulze A, Wahdan Y, Serrani M, Kroll R. Contraceptive efficacy and safety of 52mg LNG-IUS for up to 8 years: findings from the Mirena Extension Trial. Am J Obstet Gynecol. 2022 Sep 9:S0002-9378(22)00729-3. doi: 10.1016/j.ajog.2022.09.007. Epub ahead of print. PMID: 36096186.

Medha Baranwal joined Medical Dialogues as an Editor in 2018 for Speciality Medical Dialogues. She covers several medical specialties including Cardiac Sciences, Dentistry, Diabetes and Endo, Diagnostics, ENT, Gastroenterology, Neurosciences, and Radiology. She has completed her Bachelors in Biomedical Sciences from DU and then pursued Masters in Biotechnology from Amity University. She has a working experience of 5 years in the field of medical research writing, scientific writing, content writing, and content management. She can be contacted at  editorial@medicaldialogues.in. Contact no. 011-43720751