2 Clinical need and practice
2.1 Heavy menstrual bleeding (HMB, also known as menorrhagia) is a significant cause of morbidity in premenopausal women in England and Wales. HMB is objectively defined as menstrual blood loss of more than 80 ml/cycle, or menstrual bleeding lasting longer than 7 days, over several consecutive cycles. However, in practice, the diagnosis is based on the woman's subjective assessment of blood loss.
2.2 HMB is a common disorder. It is estimated that 1 in 20 women in the UK aged 30–49 years consults her GP each year with HMB – approximately 1.5 million women in England and Wales. Referrals for menstrual disorders account for about 20% of all referrals to specialist gynaecology services, placing a significant burden on secondary healthcare services.
2.3 Many women who are referred to secondary care for HMB will eventually undergo hysterectomy. More than 47,000 hysterectomies were carried out in the NHS in England in 2000–01. It is estimated that HMB was the presenting complaint in about half of these cases. Furthermore, about half of all women who have a hysterectomy for HMB are believed to have a normal uterus removed.
2.4 HMB has adverse implications for quality of life. Women with HMB may have difficulties with daily activities such as work, social activities, hobbies and holidays. Many women report anxiety, depression, embarrassment and problems in their sex lives because of HMB. Anaemia is also common amongst women with HMB, and this may further impair quality of life.
2.5 Diagnosis of HMB is complex and is usually based on subjective evaluation of blood loss by the affected individuals. The blood loss can be estimated using pictorial blood-loss assessment charts (PBACs); this method takes into account the number of items of sanitary wear used and the degree of staining of each item. A PBAC score greater than 100 would normally indicate HMB. Although the 'gold standard' method of measuring blood loss is the alkaline haematin technique, which requires women to collect their used sanitary wear, this technique is rarely used outside research settings.
2.6 The cause of HMB is not known in the majority of cases, in which no pelvic or organic pathology is identified. However, HMB may have structural organic causes such as fibroids, adenomyosis, polyps, infections, pre-cancerous conditions or haematological disorders.
2.7 Treatment of HMB aims to reduce menstrual loss and hence to improve the quality of life of the individuals. First-line treatment is drug therapy. The most commonly used drugs are tranexamic acid (an antifibrinolytic drug), mefenamic acid (a non-steroidal anti-inflammatory drug) and combined oral contraceptives. The Royal College of Obstetricians and Gynaecologists' (RCOG) guidelines recommend that drug treatment should be given for at least three cycles before considering another treatment option. Another alternative sometimes used before surgical intervention is a levonorgestrel-releasing intrauterine system.
2.8 Surgical treatment is usually offered to patients who do not respond to drug treatment. Hysterectomy (removing the uterus as a whole or in part) is the only treatment for HMB that guarantees amenorrhoea (complete cessation of menstrual periods), but it is associated with peri- and postoperative complications, including incontinence and other urinary problems, fatigue, infection, pelvic pain and sexual problems. Overall, 1 in 30 women suffers a major adverse event during or soon after the operation. Additionally, the procedure has a mortality rate of 0.4–1.1 per 1000 operations. Hysterectomy is costly and has significant resource implications because it requires general anaesthesia, long operating theatre times and a hospital stay of up to 7 days after the operation. Full recovery may take 1–3 months.
2.9 First-generation endometrial ablation (EA) techniques were introduced almost 20 years ago as alternatives to hysterectomy. These techniques aim to reduce the menstrual bleeding by destroying (ablating) the entire thickness of the innermost layer of the uterus (the endometrium) and some of the underlying muscular layer (the myometrium) using electrical, thermal or laser energy. EA techniques do not guarantee amenorrhoea, but are less invasive and require fewer resources than hysterectomy. Preoperative medical therapy is given to suppress endometrial growth, because ablation is more likely to be successful if the endometrium is thin. All organic and structural causes of HMB should be excluded before considering EA, by any means, as a treatment option. EA techniques are not suitable for women who wish to maintain fertility.
2.10 The most widely used first-generation EA techniques are transcervical resection of endometrium (TCRE), using a loop diathermy electrode, and roller-ball ablation (RB), using an electrode with a movable ball or cylinder. All first-generation EA techniques require direct visualisation of the endometrium using a hysteroscope. The success rates of these techniques depend heavily on the skills and experience of the operator.
2.11 Possible perioperative adverse effects with the firstgeneration EA techniques include electrosurgical burns, uterine perforation, haemorrhage, infection, and fluid overload (which may cause congestive cardiac failure, hypertension, haemolysis, coma and death). The incidences of complications following first-generation EA ablation techniques were reported by the MISTLETOE study (of more than 10,000 women) in England and Wales, and the Scottish Audit of Hysteroscopic Surgery (of around 1000 women). The rate of emergency hysterectomy was 6.6 per 1000 procedures in the MISTLETOE study and 2.0 per 1000 procedures in the Scottish Audit, and blunt uterine perforation was reported in 14.7 per 1000 procedures and 11.2 per 1000 procedures respectively. Combining the two audits, mortality from the first-generation EA methods was shown to be 0.26 per 1000 procedures.