Endometrial resection and ablation techniques for heavy menstrual bleeding

Heavy menstrual bleeding (HMB) is a significant health problem in premenopausal women; it can reduce their quality of life and can cause social disruption and physical problems such as iron deficiency anaemia. First-line treatment has traditionally consisted of medical therapy (hormonal and non-hormonal), but this is not always successful in reducing menstrual bleeding to acceptable levels. Hysterectomy is a definitive treatment, but it is more costly and carries some risk. Endometrial ablation may be an alternative to hysterectomy that preserves the uterus. Many techniques have been developed to 'ablate' (remove) the lining of the endometrium. First-generation techniques require visualisation of the uterus with a hysteroscope during the procedure; although it is safe, this procedure requires specific technical skills. Newer techniques for endometrial ablation (second- and third-generation techniques) have been developed that are quicker than previous approaches because they do not require hysteroscopic visualisation during the procedure.

To compare the efficacy, safety, and acceptability of endometrial destruction techniques to reduce heavy menstrual bleeding (HMB) in premenopausal women.

We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, CINAHL, and PsycInfo (from inception to May 2018). We also searched trials registers, other sources of unpublished or grey literature, and reference lists of retrieved studies, and we made contact with experts in the field and with pharmaceutical companies that manufacture ablation devices.

Randomised controlled trials (RCTs) comparing different endometrial ablation or resection techniques for women reporting HMB without known uterine pathology, other than fibroids outside the uterine cavity and smaller than 3 centimetres, were eligible. Outcomes included improvement in HMB and in quality of life, patient satisfaction, operative outcomes, complications, and the need for further surgery, including hysterectomy.

Two review authors independently selected trials for inclusion, assessed trials for risk of bias, and extracted data. We contacted study authors for clarification of methods or for additional data. We assessed adverse events only if they were separately measured in the included trials. We undertook comparisons with individual techniques as well as an overall comparison of first- and second-generation ablation methods.

We included in this update 28 studies (4287 women) with sample sizes ranging from 20 to 372. Most studies had low risk of bias for randomisation, attrition, and selective reporting. Less than half of these studies had adequate allocation concealment, and most were unblinded. Using GRADE, we determined that the quality of evidence ranged from moderate to very low. We downgraded evidence for risk of bias, imprecision, and inconsistency.Overall comparison of second-generation versus first-generation (i.e. gold standard hysteroscopic ablative) techniques revealed no evidence of differences in amenorrhoea at 1 year and 2 to 5 years' follow-up (risk ratio (RR) 0.99, 95% confidence interval (CI) 0.78 to 1.27; 12 studies; 2145 women; I² = 77%; and RR 1.16, 95% CI 0.78 to 1.72; 672 women; 4 studies; I² = 80%; very low-quality evidence) and showed subjective improvement at 1 year follow-up based on a Pictorial Blood Assessment Chart (PBAC) (< 75 or acceptable improvement) (RR 1.03, 95% CI 0.98 to 1.09; 5 studies; 1282 women; I² = 0%; and RR 1.12, 95% CI 0.97 to 1.28; 236 women; 1 study; low-quality evidence). Study results showed no difference in patient satisfaction between second- and first-generation techniques at 1 year follow-up (RR 1.01, 95% CI 0.98 to 1.04; 11 studies; 1750 women; I² = 36%; low-quality evidence) nor at 2 to 5 years' follow-up (RR 1.02, 95% CI 0.93 to 1.13; 672 women; 4 studies; I² = 81%).Compared with first-generation techniques, second-generation endometrial ablation techniques were associated with shorter operating times (mean difference (MD) -13.52 minutes, 95% CI -16.90 to -10.13; 9 studies; 1822 women; low-quality evidence) and more often were performed under local rather than general anaesthesia (RR 2.8, 95% CI 1.8 to 4.4; 6 studies; 1434 women; low-quality evidence).We are uncertain whether perforation rates differed between second- and first-generation techniques (RR 0.32, 95% CI 0.10 to 1.01; 1885 women; 8 studies; I² = 0%).Trials reported little or no difference between second- and first-generation techniques in requirement for additional surgery (ablation or hysterectomy) at 1 year follow-up (RR 0.72, 95% CI 0.41 to 1.26; 6 studies: 935 women; low-quality evidence). At 5 years, results showed probably little or no difference between groups in the requirement for hysterectomy (RR 0.85, 95% CI 0.59 to 1.22; 4 studies; 758 women; moderate-quality evidence).

Approaches to endometrial ablation have evolved from first-generation techniques to newer second- and third-generation approaches. Current evidence suggests that compared to first-generation techniques (endometrial laser ablation, transcervical resection of the endometrium, rollerball endometrial ablation), second-generation approaches (thermal balloon endometrial ablation, microwave endometrial ablation, hydrothermal ablation, bipolar radiofrequency endometrial ablation, endometrial cryotherapy) are of equivalent efficacy for heavy menstrual bleeding, with comparable rates of amenorrhoea and improvement on the PBAC. Second-generation techniques are associated with shorter operating times and are performed more often under local rather than general anaesthesia. It is uncertain whether perforation rates differed between second- and first-generation techniques. Evidence was insufficient to show which second-generation approaches were superior to others and to reveal the efficacy and safety of third-generation approaches versus first- and second-generation techniques.