The hormone-releasing Mirena coil intrauterine device (IUD) is a better treatment for heavy menstrual periods than other conventional medical approaches, according to results of a major clinical trial led by scientists from the Universities of Birmingham and Nottingham.

The findings of the ECLIPSE study, published online today in the New England Journal of Medicine, are widely expected to change standard clinical practice.

Heavy periods, or menorrhagia, affect the lives of large numbers of women aged 25-50 years, accounting for many GP consultations and 20 per cent of gynaecological referrals in the UK. Yet to date there has been limited evidence to help women and doctors make informed choices about treatments.

The ECLIPSE trial compared the clinical effectiveness of the levonorgestrel-releasing intrauterine system (also known as LNG-IUS or the Mirena contraceptive coil) with other medical treatments on offer in primary care.

A total of 571 women, consulting their GPs for heavy menstrual bleeding, agreed to be randomly assigned to LNG-IUS or to another standard medical treatment, such as tranexamic acid, mefanamic acid, combined estrogen and progestogen or progestogen only. 

Over two years, patient reported outcomes improved more with LNG-IUS than with other treatments, including women’s experience of practical difficulties, social, family and work life, and psychological and physical health.

Women allocated to LNG-IUS were almost twice as likely to still be using it than those taking other medication after two years. Some 49 per cent of other trial participants switched to LNG-IUS citing ‘lack of effectiveness’ as the reason for stopping other treatments.

Janesh Gupta, Professor of Obstetrics and Gynaecology at the University of Birmingham and based at Birmingham Women’s Hospital, said: “While the interventions studied in this trial represent options available in primary care settings in the UK, insertion of IUDs is not part of primary care in all health care settings, and in some circumstances requires gynaecologist consultation.  This trial should encourage the use of IUDs in primary care.

“Both LNG-IUS and usual medical treatments reduced the adverse impact of menorrhagia on women’s lives over two years but this trial shows that LNG-IUS is the more effective first choice, as assessed by the impact of bleeding on women’s quality of life.”

Joe Kai, a GP and Professor of Primary Care at The University of Nottingham, said: “We hope our results are very positive news for women and their GPs. This trial tells us not only that treatments can be effective, but also what to choose, bearing in mind a woman’s preferences for having a contraceptive IUS inserted or not. 

“Heavy menstrual bleeding can be very debilitating but we know many do not seek help. We need to make women more aware beneficial treatments are available, and to offer options such as LNG-IUS more often.”

Levonorgestrel Intrauterine System versus Medical Therapy for Menorrhagia. Janesh Gupta1*, M.D.; Joe Kai2*, M.D.; Lee Middleton3, M.Sc.; Helen Pattison4, Ph.D.; Richard Gray5, M.Sc.; Jane Daniels1,3, M.Sc.; for the ECLIPSE trial collaborative group.

*Joint first authors

For more information, please contact Jenni Ameghino, Media Relations Manager, University of Birmingham, 0121 415 8134 Mobile: 07768 924156 or Emma Rayner, Media Relations Manager, The University of Nottingham, 0115 951 5793 Mobile: 07738291242

For a short video on the research findings please visit:

Effectiveness and Cost-effectiveness of Levonorgestrel-containing Intrauterine system in Primary care against Standard treatment for menorrhagia (ECLIPSE). New England Journal of Medicine.

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