Endometrial Ablation

Anatomy and Physiology

Before performing endometrial ablation, evaluating the underlying cause of abnormal uterine bleeding is essential to ensure appropriate management. Abnormal uterine bleeding has a wide array of etiologies, which can be classified using the PALM-COEIN (polyp, adenomyosis, leiomyoma, malignancy; coagulopathy, ovulatory dysfunction, endometrial, iatrogenic, and not yet classified) classification system developed by The International Federation of Gynecology and Obstetrics (FIGO) and has become a universally accepted terminology. These PALM-COEIN etiologies can be divided into structural groups, comprising polyps, adenomyosis, leiomyomas, or malignancies, and nonstructural groups, which include coagulopathies, ovulatory dysfunction, and conditions that are endometrial, iatrogenic, and not yet classified.[7]

A transvaginal ultrasound, endometrial biopsy, saline infusion sonogram, or hysteroscopy may be used to determine structural abnormalities and provide information on the size and position of the uterus. Nonstructural causes of abnormal uterine bleeding can be due to endocrinopathies; underlying bleeding disorders, such as von Willebrand disease; or iatrogenic causes, such as various contraceptive methods or medications, including anticoagulants.[7] Endometrial hyperplasia or malignancy is an underlying cause of abnormal uterine bleeding and should be excluded through endometrial histopathological analysis before performing an endometrial ablation. Please see StatPearls' companion resource, "Abnormal Uterine Bleeding," for more information.

The endometrial lining of the uterine cavity consists of 2 layers—the functional layer and the basal layer. The functional layer performs physiological functions such as proliferation, maintenance of pregnancy, and menstruation, whereas the basal layer is implicated in the regrowth of the functional layer.[8][9] The various endometrial ablation techniques destroy the endometrial lining, removing the functional and basal layers.[10] By destroying these layers, endometrial regeneration is reduced or ceased, resulting in a decreased menstrual flow or complete amenorrhea.[2][6] After endometrial ablation, necrosis, fibrosis, and inflammation are common histological findings of the uterine cavity.[11]

Indications

Indicators for Patient Selection

Endometrial ablation is used to treat heavy abnormal uterine bleeding. Appropriate patient selection is crucial when determining the most suitable approach for managing abnormal uterine bleeding.[6] The ideal candidate for endometrial ablation is a patient with endometrium, as determined by the FIGO classification system, and does not desire definitive management through a hysterectomy.[12][13] The following clinical factors indicate patients for whom endometrial ablation is recommended:

• Patients of reproductive age with heavy menstrual bleeding that significantly impacts their quality of life due to a benign cause who have met their desired parity.
• Abnormal uterine bleeding without uterine abnormalities or with fibroids <3 cm in diameter.
• Abnormal uterine bleeding unrelated to hyperplasia or malignancy confirmed by endometrial biopsy.
• Abnormal uterine bleeding with failure or intolerance of medical management.
• Nonsurgical candidates due to surgical risks or preexisting comorbidities.
• Uterine cavity with a length <10 cm and a smooth contour, as determined by a preoperative transvaginal ultrasound or saline infusion sonogram. [6]

Contraindications

Contraindications to endometrial ablation include:

• Pregnancy or desire for fertility preservation
• Endometrial hyperplasia or uterine malignancy
• Cervical cancer
• Active pelvic infection
• Retained intrauterine device
• History of transmyometrial uterine surgery or cesarean section
• Uterine anomalies, such as septate, bicornuate, or unicornuate uterus.[6][14][15]

Relative contraindications include:

• Postmenopausal state
• Submucous leiomyomas
• Uterine cavity length >11 cm
• Severe myometrial thinning
• Severe uterine retroflection or anteflexion [12][11][16]

Personnel

The personnel required to perform an endometrial ablation typically include a gynecologist and an assistant. Endometrial ablation may be performed in the outpatient setting or an operating room.

Preparation

Before performing an endometrial ablation, clinicians should discuss the patient's expectations of menstrual bleeding after the procedure. The goal is to decrease the amount of heavy menstrual bleeding, improving the patient's quality of life. Patients who desire amenorrhea may not be good candidates for endometrial ablation, as this outcome is not guaranteed with endometrial ablation.[6] The rates of amenorrhea range between 15% and 72% 12 months after the procedure.[12] 

Counseling on future fertility and reliable contraception is also necessary because pregnancy after ablation carries high risks. Endometrial histology should be evaluated with endometrial biopsy. Uterine structure, including size, position, and cavity contour, should be assessed using various ultrasonographic modalities before the procedure.[5][6] Endometrial ablation can be performed as an in-office procedure, which does not require general anesthesia, or as an outpatient procedure with general anesthesia; preoperative anesthesia evaluation and counseling should be tailored accordingly.[6]

Technique or Treatment

The effectiveness of endometrial ablation is based on removing or destroying the basal layer of the endometrium, which is crucial in preventing regrowth of the uterine lining. Historically, heavy menstrual bleeding was treated with either medications or a hysterectomy, both of which remain effective options. However, more recent treatments have shifted toward addressing the endometrium, the uterine lining that causes the bleeding. These newer methods either involve removing the endometrial lining through resection or destroying it with thermal energy in a procedure called ablation. These approaches have been shown to reduce or stop menstrual bleeding effectively.[10] A recent Cochran review found that first- and second-generation approaches are equally effective in treating heavy menstrual bleeding, with similar patient satisfaction rates. However, second-generation techniques showed decreased rates of some adverse outcomes, including fluid overload, cervical lacerations, and hematometra.[10]

Over the past few decades, endometrial ablation techniques have evolved significantly, providing less invasive alternatives to hysterectomy for treating heavy menstrual bleeding. These techniques were primarily divided into first- and second-generation endometrial ablation techniques based on the need to visualize the endometrium with hysteroscopy during the ablation procedure.[5][6] Third-generation methods have further refined the ablation process, improving on second-generation approaches.[10] The specific procedures followed vary based on the ablation device used. Therefore, clinicians should follow manufacturers' guidelines when performing endometrial ablation procedures according to the device used.

First-Generation Techniques

Initially, first-generation techniques, such as laser photovaporization, rollerball ablation, and transcervical resection of the endometrium, were developed to treat heavy menstrual bleeding. These methods required direct visualization of the uterine cavity with a hysteroscope. Despite their effectiveness, these methods had limitations, including the need for a skilled surgeon, general anesthesia, and an operating room environment. In addition, these procedures were associated with a higher rate of complications, such as hemorrhage and uterine perforation. As these methods were complex and had associated patient morbidity, the expected reduction in hysterectomy rates was not fully realized.[5]

Second-Generation Techniques

In response to the deficiencies observed with the first-generation ablation methods, second-generation techniques were introduced, offering options that are easier to perform, equally effective, and associated with lower complication rates. Endometrial visualization is unnecessary with these newer methods, which include thermal balloon, microwave, hydrothermal, bipolar radiofrequency, and cryotherapy techniques.[6] These procedures can often be performed in outpatient settings, often under local anesthesia, and do not require the advanced hysteroscopic skills required for first-generation procedures. Second-generation techniques are associated with shorter procedure times and lower complication rates. These advancements have made endometrial ablation more accessible and cost-effective, leading to broader adoption and a significant impact on treatment options for women with heavy abnormal uterine bleeding. Despite these advantages, current evidence does not definitively show that any second-generation method is superior to another, and there remains some uncertainty regarding the comparative safety and efficacy between first- and second-generation techniques.[10]

Third-Generation Techniques

The development of third-generation techniques, which improve upon earlier methods by enhancing safety and effectiveness, continues to refine the practice of endometrial ablation. Third-generation methods offer improvements such as better heat distribution across the endometrial surface. For example, the Thermachoice III system, which replaces latex with silicone in the balloon and utilizes active fluid circulation, provides more consistent heat application. These advancements aim to enhance the safety and effectiveness of the procedure.[10] However, the choice of technique often depends on the availability of specific equipment and the surgeon's experience. Despite the advancements, there remains a need for ongoing research to optimize outcomes and patient satisfaction with these techniques.[5]

Complications

First-generation endometrial ablation techniques have an estimated complication rate of 4.4%, whereas second- and third-generation techniques have a complication rate of approximately 1%.[10] Postoperative complications include:

• Perforation of pelvic organs
• Endometritis
• Myometritis
• Cervical lacerations or stenosis
• Pelvic sepsis
• Pelvic abscess
• Pelvic inflammatory disease
• Hematometra
• Uterine tamponade
• Blood transfusion
• Glycine toxicity
• Fluid overload
• Fluid deficit
• Bowel obstruction
• Urinary incontinence
• Pelvic pain [10]
• Gas embolism
• Thermal injury
• Hemorrhage
• Intrauterine adhesions [6]
• Vesicouterine fistula [14]
• Pregnancy-related complications, such as premature birth, abnormal placentation, intrauterine growth restriction, and perinatal mortality
• Postablation tubal sterilization syndrome, characterized by cyclic pelvic pain due to endometrial regrowth and distension of the uterine cornua with blocked fallopian tubes in patients who have undergone bilateral tubal ligation and endometrial ablation [17]
• Missed or delayed diagnosis of uterine carcinoma [13][11][18]

Clinical Significance

Traditionally, heavy menstrual bleeding was managed with medications or hysterectomy, which are still reliable treatments. However, newer options focus on targeting the endometrium, the uterine lining responsible for the bleeding. These newer treatments either remove the endometrium through resection or destroy it using thermal energy, a process known as ablation. These procedures have proven effective in reducing or eliminating menstrual bleeding.[10]

Although first-generation methods were more invasive and required a higher level of technical skill, the newer second- and third-generation techniques are easier to perform, less invasive, and have become increasingly popular alternatives to hysterectomy. Overall, most patients have a satisfactory outcome in treating heavy menstrual bleeding. Both first- and second-generation methods have shown equal efficacy in outcomes.[6][5] At 12 months after a nonresectoscopic endometrial ablation, 82% to 97% of patients showed decreased menstrual bleeding, and 85% to 98% were satisfied with their outcome.[12]

As a result, the number of hysterectomies performed for heavy menstrual bleeding has significantly decreased. However, long-term studies indicate that some women may still require a hysterectomy following ablation, particularly in the years immediately after the procedure. Failure rates for endometrial ablations range from 5% to 16% within 5 years of undergoing the procedure, with patients requiring definitive hysterectomy to treat persistent pelvic pain or bleeding.[2]

Endometrial Ablation Compared to Nonsurgical Therapies

Among nonsurgical treatments, the levonorgestrel-releasing intrauterine system (LNG-IUS) is the most effective first-line option for reducing menstrual blood loss, offering a 71% to 95% reduction in blood loss. This effectiveness makes LNG-IUS comparable to hysterectomy when considering quality-adjusted life years. Antifibrinolytics, such as tranexamic acid, and long-cycle progestogens are also effective, but to a lesser extent, with reductions in menstrual blood loss ranging from 26% to 87%, depending on the specific treatment. Oral contraceptives also offer substantial reductions (35% to 69%), but continuous dosing of progestins, although effective, often has lower long-term patient satisfaction.[19][20][1]

Endometrial ablation is highly effective in controlling bleeding.[1] Studies show that endometrial resection provides better bleeding control at short-term follow-ups (for example, 4 months and 2 years) compared to oral medications. However, this difference diminishes over extended periods (for example, 5 years). Unlike pharmacological treatments, which are reversible and preserve fertility, endometrial ablation is more invasive and typically considered when less invasive treatments fail or when fertility preservation is not a concern.[1][19]

Patient satisfaction with treatment outcomes varies between pharmacologic and surgical options. LNG-IUS is associated with high satisfaction rates, comparable to those observed with more invasive surgical options. In contrast, although suitable for some women, oral medications may not maintain high satisfaction over the long term. Endometrial ablation, particularly when compared to conservative surgical options, generally yields higher satisfaction rates in the short term (for example, at 1 year). However, over longer follow-ups, the difference in satisfaction between ablation and medical treatments such as LNG-IUS becomes less pronounced.[19][20]

The LNG-IUS and oral contraceptives have the advantage of being noninvasive and carrying fewer immediate risks compared to surgery. However, they may be associated with ongoing bleeding, spotting, or hormonal side effects. Although effective and generally well-tolerated, endometrial ablation carries risks associated with surgery. In addition, ablation is not suitable for women who wish to preserve fertility, as it typically results in permanent changes to the endometrial lining. Endometrial ablation offers a middle ground—less invasive than hysterectomy but more permanent and effective compared to most pharmacologic options. For many women, particularly those who prefer to avoid surgery or preserve fertility, the LNG-IUS offers a highly effective and satisfactory long-term solution with a lower risk profile.[19][20][1]

Although endometrial ablation provides a more definitive and immediate solution to heavy menstrual bleeding, pharmacological treatments, particularly the LNG-IUS, offer effective, less invasive alternatives that preserve fertility and have favorable safety profiles. Therefore, the choice between these options should be individualized, including the patient's desire for fertility preservation, tolerance for potential adverse effects, and preference for nonsurgical versus surgical interventions.[19][20][1]

Endometrial Ablation Compared to Hysterectomy

Historically, nearly half of all hysterectomies have been performed globally to treat abnormal uterine bleeding. Hysterectomy provides the definitive treatment for heavy uterine bleeding by eliminating menstruation and generally results in high patient satisfaction. However, hysterectomy is also a major surgery associated with significant physical risks, social implications, and higher costs. The associated risks and costs vary somewhat based on the hysterectomy method, such as abdominal and minimally invasive hysterectomies. Despite its effectiveness, many women seek less invasive alternatives even when informed that these alternatives may not guarantee complete success.[5]

When comparing minimally invasive hysterectomy and endometrial ablation, hysterectomy guarantees the cessation of menstruation but comes with significant risks and recovery time. In contrast, endometrial ablation offers a less invasive option with quicker recovery, although it may not always be as effective, and some women may eventually require further surgery. Both treatments have similar safety profiles regarding serious complications, but the choice between hysterectomy and endometrial ablation often depends on the patient's preference for a less invasive procedure versus the certainty of results.[5]

Enhancing Healthcare Team Outcomes

Endometrial ablation requires a coordinated effort among a diverse team of healthcare professionals, each contributing specific skills and responsibilities to ensure patient-centered care, optimize outcomes, and enhance patient safety. Clinicians, who often lead the procedure, are responsible for assessing patients, determining candidacy for ablation, and performing the surgery with precision. Advanced practitioners, such as nurse practitioners or clinician assistants, play a crucial role in preoperative and postoperative care. They assess patient readiness, provide education about the procedure, manage perioperative care, and monitor for complications. Nurses are vital in both the preoperative and postoperative phases, providing patient education, managing anxiety, and monitoring vital signs. Nurses also play a crucial role in ensuring adherence to safety protocols, which are critical for preventing complications.

Effective interprofessional communication and care coordination are crucial for the success of endometrial ablation. Clear documentation and standardized communication tools help ensure that all team members are on the same page, reducing the risk of errors and improving patient outcomes. Each professional must understand their role and how it fits into the larger care plan, working collaboratively to address any issues and ensuring that the patient receives comprehensive, patient-centered care. Through shared responsibilities and effective communication, the healthcare team can provide high-quality care tailored to the individual needs of the patient undergoing endometrial ablation.