Mirena: the other side of the story

Correspondence
Mirena: the other side of the story
Sir,
I read with interest the article by Halmesmaki et al.1 that only
48.7% of women randomised to the levonorgestrel (LNG)releasing intrauterine system Mirena, kept it in situ until
their 5 years follow-up visit, while the rest either had it prematurely removed (8.5%) or underwent a hysterectomy
(42.7%). It supports the growing evidence that women’s satisfaction with Mirena (Schering Health, Newbury, UK) is
limited. I do not find this surprising. A colleague and myself
previously reported (as an abstract) a survey including 160
Mirena users in Suffolk in which we found that 46% of
women had had the system removed within 3 years
of insertion (median duration = 260.5 days; range = 4–1460
days). The most common reasons for early removal were
unscheduled bleeding, abdominal pain and progestogenic
adverse effects; including bloatedness, headache, weight gain,
depression, breast tenderness, excessive hairiness, greasiness
of skin and lack of sexual interest.2 Our data related to
a selected population who had the Mirena inserted under
general anaesthetic after hysteroscopic examination of uterine
cavity to exclude lesions, such as submucous fibroids. I would
expect the continuation rate to be lower in women having the
system inserted without prior exclusion of intrauterine
pathology. The satisfaction rate in our cohort of women, as
assessed by visual analogue scale of 0–10 cm, was only 49%
(unpublished data).
Halmesmaki et al.1 reasonably attributed the detrimental
effect of Mirena on the sexual function to the higher incidence
of lower abdominal pain in users when compared with those
who underwent hysterectomy. Furthermore, the decreased
satisfaction of sexual partners could be due to the inhibiting
effect of the irregular bleeding, which is the most common
adverse effect of using Mirena.2,3 The observed decrease in
women’s sex drive could also be due to the systemic effect
of the progestogen absorbed into the circulation, indirectly
affecting the sexual partner. The argument used by the
authors that serum concentration of LNG is extremely low
and that its influence on ovarian function is limited has been
disputed recently by many investigators. Xiao et al.4 found
that Mirena was associated with substantial systemic absorption of LNG and recorded serum levels of around 500 pmol/l.
This is equivalent to two LNG-containing ‘minipills’ taken
ª 2007 The Authors Journal compilation ª RCOG 2007 BJOG An International Journal of Obstetrics and Gynaecology
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Correspondence
daily on a continuous basis. Moreover, a retrospective
observational study documented that 21% of Mirena users
experienced progestogenic adverse effects.3 Wahab and
Al-Azzawi5 reported that Mirena suppresses oestrogen production, inducing a clinical situation similar to a premature
menopause in at least 50% of treated women. The prolonged
oestrogen deprivation will have a profound negative effect on
women’s sex drive, which may explain the sexual partners’
decreased satisfaction.
In fact, despite the popularity of Mirena as a contraceptive
method and in treating menorrhagia, the continuation rate
and women satisfaction level have not been adequately
assessed in the UK population. A large well-designed study
is required to evaluate these important factors so that women
can be adequately counselled. The idea that Mirena works
entirely as a local source of progestogen should be revised,
and the recent concerns about Mirena should be made clear
to women regardless of the marketing pressures.5 j
References
1 Halmesmaki K, Hurskainen R, Teperi J, Grenman S, Kivela A, Kujansuu E,
et al. The effect of hysterectomy or levonorgestrel-releasing intrauterine system on sexual functioning among women with menorrhagia: a 5-year randomised controlled trial. BJOG 2007;114:563–8.
2 Daud S, Ewies A. Continuation rate and reasons of early removal of the
levonorgestrel-releasing intrauterine system. Endocr Abstr 2006;12:P93.
3 Macnab JL, Lowles IE. Levonorgestrel-releasing intrauterine system
for menstrual dysfunction: patient satisfaction in the district general
hospital setting. J Obstet Gynaecol 2002;22:402–5.
4 Xiao B, Wu SC, Chong J, Zeng T, Han LH, Luukkainen T. Therapeutic
effects of the levonorgestrel-releasing intrauterine system in the treatment of idiopathic menorrhagia. Fertil Steril 2003;79:963–9.
5 Wahab M, Al-Azzawi F. The use of levonorgestrel-releasing intrauterine
system for treatment of menorrhagia in women with inherited bleeding disorders. BJOG 2005;112:1455–6.
AAA Ewies
Consultant Gynaecologist, The Ipswich Hospital NHS Trust, Suffolk, UK
Accepted 23 May 2007.
DOI: 10.1111/j.1471-0528.2007.01439.x
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ª 2007 The Authors Journal compilation ª RCOG 2007 BJOG An International Journal of Obstetrics and Gynaecology