Expert Commentary
What are the risk factors for pain after endometrial ablation?
A history of dysmenorrhea or tubal sterilization increases the likelihood of new or worsening postablation pain by 74% (adjusted odds ratio [OR],...
Over the past year, as we have increased adoption of the PALM-COEIN classification system for the causes of AUB in women of reproductive age, we also have gleaned more information about how endometrial ablation works in this context. In general, PALM (polyp, adenomyosis, leiomyoma, and malignancy/hyperplasia) represents lesions that can be seen but may not necessarily be the cause of bleeding. COEIN (coagulopathy, ovulatory dysfunction, endometrial factors, iatrogenic, and not yet classified) represents causes of bleeding that may not be visible.
Although endometrial ablation is ideally suited for women with AUB related to endometrial factors (AUB-E), two studies from 2014 provide insight into endometrial ablation performed when lesions are present within the PALM classification, such as polyps (AUB-P), adenomyosis (AUB-A), and leiomyomas (AUB-L), and in patients with COEIN conditions, such as ovulatory dysfunction (AUB-O) and AUB-E.
Findings of Wishall and colleagues
Three hundred women who underwent endometrial ablation were evaluated in regard to postoperative pain and the need for subsequent hysterectomy. A total of 270 women were available for follow-up in this retrospective cohort (10% lost to follow-up). Wishall and colleagues set out to identify prognostic factors that would put a woman at risk for post-ablation pain. Their secondary outcome was the rate of hysterectomy after ablation.
The study was limited to second-generation endometrial ablation devices, including the thermal balloon, microwave, circulating hot fluid, and bipolar radiofrequency devices.
Wishall and colleagues found that the risk of failure was the highest (a quadrupling) when uterine abnormalities such as leiomyomas, adenomyosis, a thickened endometrial stripe, or polyps were present (adjusted odds ratio [OR], 3.96; 95% confidence interval [CI], 1.25–12.56).
As in other series, 19% of women ultimately required hysterectomy. Twenty-three percent developed new or worsening pain after ablation. Risk factors for postablation pain included a history of dysmenorrhea (OR, 1.74) and tubal sterilization (OR, 2.06).
Findings of Smithling and colleagues
Investigators evaluated the records of 968 women with AUB who had undergone endometrial ablation, categorizing their preoperative bleeding patterns as either regular (presumed AUB-E) or irregular (presumed AUB-O). Of these women, 961 (99.3%) had undergone radiofrequency bipolar endometrial ablation.
Smithling and colleagues hypothesized that women with AUB-O would have a higher failure rate—defined as the need for reablation or subsequent hysterectomy—than women with AUB-E because endometrial ablation does not necessarily address the pathology that underlies AUB-O. However, they found no difference in treatment failure or the need for a subsequent gynecologic procedure between groups during the 3-year period after endometrial ablation. The rate of treatment failure was 16.4% in women with regular bleeding—essentially the same as the rate for women with irregular bleeding (17.6%; P = .7) Risk factors associated with failure included:
- tubal sterilization (16.4% vs 9.0% for women without it)
- pelvic pain or dysmenorrhea (21.8% vs 10.7% for women without it)
- obesity (16.7% vs 9.8%) (P = .003).
Although there was no difference in failure rates between the group with regular bleeding versus the group with irregular bleeding, Smithling and colleagues were careful to avoid interpreting this finding as a recommendation for endometrial ablation in women with AUB-O.
What this EVIDENCE means for practice
When endometrial ablation is performed to treat lesions such as polyps, adenomyosis, and leiomyomata, women are nearly four times more likely to require subsequent hysterectomy.
A history of dysmenorrhea yielded a 74% higher risk of developing postablation pain, and a history of tubal sterilization more than doubled the risk, compared with no history of dysmenorrhea or tubal sterilization.
Women who undergo endometrial ablation for presumed AUB-O and presumed AUB-E have similar failure rates.
Preoperative factors such as dysmenorrhea, prior tubal sterilization, and obesity were identified as risk factors for ablation failure.
The choice between endometrial ablation and hysterectomy for patients with AUB-O depends on an individualized assessment of risks and benefits, including evaluation of medical comorbidities.
Share your thoughts on this article! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.
