The relationship between leiomyomas and infertility remains a subject for debate. The incidence of myomas in infertile women without any obvious cause of infertility is estimated to be between 1% and 2.4% [4
]. However, there are no studies that compare pregnancy rates in women with and without fibroids, and the causal relationship seems to have been assumed from case studies of women who have conceived after their fibroids were removed [5
A shift in cultural trends of women delaying pregnancy has resulted in many women presenting with symptomatic fibroids at a stage when preservation of the uterus is a priority. The National Office of Statistics in the United Kingdom reports a 74% increase in the number of conceptions in the 40-44 age group in 2004, when compared to that of 1988 [?]. This has resulted in a dilemma for the gynaecologist who is faced with providing an effective solution to his patient’s fibroid symptoms, while ensuring no detrimental effect on her fertility. The current standard of practice remains surgical in the many forms of myomectomy (laparotomy, laparoscopy, hysteroscopy).
Despite myomectomy being the gold standard, few studies agree on the actual increase in pregnancy rates following surgery, this being described as anything from 44%-81%; however, all report a fall in the rate of pregnancy loss [6
Unfortunately fertility enhancement is not the only factor to be considered when recommending treatment; complications related to fibroid removal also have to be taken into account. During myomectomy, part of the uterine wall is severed in order to enucleate the fibroid. This damage to the wall is independent of the surgical technique used. Surgical sutures are placed in order to control bleeding and close the severed uterine wall, which results in a fibrotic scar. In addition to the resulting relative weakness of the uterine wall post-surgery – which may result in the low but major risk of uterine rupture during pregnancy/labour – adhesions can also form within the abdomen, resulting in mechanical infertility.
A further point to be considered is the risk of surgery-associated complications. Even if uncommon, intra-operative complications, such as bladder, bowel, ureteral injury, severe bleeding and unintended conversion to hysterectomy, have been reported. Moreover, post-operative complications, such as fistula or thrombosis and embolism, may also occur [10
]. The minimally invasive treatment option of UAE has increased in popularity and reported pregnancies following treatment are plentiful. Although most pregnancies following UAE have good outcomes, the risk of pre-term delivery, spontaneous abortion, abnormal placentation and post-partum haemorrhage, are increased following uterine artery embolisation compared to myomectomy. This may be due to the resultant ischaemia, which not only occurs in the fibroid, but the entire uterus. This ischaemia may result in chronic weakness of the pregnant uterus. Uterine rupture has been reported with both myomectomy and UAE.
Although both myomectomy and UAE are seen as effective and safe treatment options for fibroids, the increase in pregnancy complications seen with UAE means that patients desiring future fertility should be recommended myomectomy as the treatment of choice over UAE.
With MRgFUS, heat ablation is limited to the core of the fibroid and no damage to the surrounding uterine wall occurs. Real-time monitoring of the volume of ablation enables limitation of the thermal damage to a distinct targeted region of the fibroid as shown in pathology specimens [11
] and MR-contrast imaging. Accordingly, there arises the hypothesis that MRgFUS may enable non-invasive treatment of uterine fibroids in women desiring pregnancy, without compromise to the integrity of the uterus or increase in pregnancy-related risks.
This out-patient procedure with minimal sedation requirements and a speedy recovery time, allows patients to return to work within 24 hours, compared to 10 days after UAE and 6 weeks with myomectomy. Over 4000 women with symptomatic uterine fibroids have been treated worldwide. Published studies have shown that up to 84.6% of women treated experienced significant symptomatic improvement at 24 months post-treatment follow up [12
]. However, initial FDA guidelines still recommend that only women who have completed their families undergo this treatment, despite there having been three published studies of achieved pregnancies following MRgFUS treatment [13
This paper describes the first pregnancy and successful delivery in a woman who was part of a fertility trial and specifically treated with MRgFUS for symptomatic fibroids that had caused a previous premature delivery at 28 weeks.
Fertility data continues to accumulate and the results are encouraging. MRgFUS appears to be a safe fertility-preserving treatment option for fibroids.