Highlights
- Endometrial polyps are significant contributors to abnormal uterine bleeding (AUB-P), with intermenstrual bleeding being the hallmark symptom in premenopausal women.
- Transvaginal ultrasonography (TVUS) remains the initial screening tool, but sonohysterography offers superior sensitivity and specificity for confirming intrauterine focal lesions.
- The therapeutic paradigm has shifted toward hysteroscopic polypectomy, preferably performed in a clinic or office setting to minimize costs and avoid systemic anesthesia.
- Malignant transformation is rare in reproductive-aged women but increases significantly in postmenopausal patients and those using tamoxifen.
Background
Endometrial polyps represent a common clinical entity in gynecological practice, characterized by localized overgrowths of endometrial glands, stroma, and blood vessels covered by an epithelial layer. While often benign, these lesions are central to the diagnostic workup of abnormal uterine bleeding (AUB) and are frequently encountered during infertility investigations. The prevalence of endometrial polyps correlates with age, peaking in the fifth decade of life, and is further influenced by systemic factors such as obesity, hypertension, and the use of selective estrogen receptor modulators like tamoxifen.
Historically, the management of these polyps relied on blind dilation and curettage (D&C), a method now largely discredited due to its low sensitivity in identifying focal lesions. The modern clinical focus has pivoted toward minimally invasive diagnostic imaging and targeted hysteroscopic intervention. Despite their prevalence, several controversies persist, particularly regarding the role of asymptomatic polyps in infertility and the optimal management of small polyps discovered incidentally. This review synthesizes the latest evidence from the Han and Munro (2026) guidelines and related clinical literature to provide a comprehensive framework for the management of endometrial polyps.
Key Content
Pathophysiology and Epidemiological Risk Factors
Endometrial polyps result from a focal monoclonal proliferation of endometrial stroma, which subsequently leads to the overgrowth of glands and vessels. Unlike the surrounding functional endometrium, the stroma of a polyp often exhibits a decreased response to progesterone, potentially due to altered receptor expression.
Key risk factors include:
- Age and Menopausal Status: Prevalence increases with age; however, the risk of malignancy within a polyp is substantially higher in postmenopausal women (estimated between 1% and 5%) compared to premenopausal women (usually <1%).
- Obesity: Elevated BMI is associated with an increased estrogenic environment, which can drive endometrial proliferation.
- Tamoxifen Therapy: Patients treated for breast cancer with tamoxifen are at a uniquely high risk (up to 30-60%) for developing endometrial polyps, which are also more likely to exhibit atypia or malignancy in this cohort.
- Ovulatory Disorders: Chronic anovulation leads to unopposed estrogen, a known stimulator of endometrial focal growth.
Diagnostic Advancements: From TVUS to Sonohysterography
Diagnosis typically follows a stepwise progression. Transvaginal ultrasonography (TVUS) is the standard first-line imaging modality. While effective for screening, its sensitivity is limited when polyps are small or when the endometrium is thick (secretory phase).
Sonohysterography (SIS): Han and Munro (2026) emphasize the high diagnostic yield of sonohysterography. By instilling saline into the uterine cavity, SIS provides an acoustic window that outlines the polyp, allowing for precise localization and measurement. It is more cost-effective than diagnostic hysteroscopy and more accurate than TVUS alone in distinguishing polyps from submucosal leiomyomas (FIGO Type 0, 1, or 2).
Doppler Imaging: The use of color and power Doppler can identify the ‘pedicle artery sign,’ which is highly suggestive of a polyp. While Doppler may assist in characterizing the vascularity of a lesion, it currently lacks the specificity required to definitively differentiate benign polyps from those with malignant potential (endometrial carcinoma or atypical hyperplasia). Therefore, histopathologic evaluation remains the gold standard for all symptomatic or high-risk lesions.
The Role of Polyps in Infertility and Assisted Reproduction
One of the most debated areas in reproductive medicine is the impact of polyps on fertility. Polyps are thought to interfere with embryo implantation through mechanical disruption or by altering the biochemical milieu of the endometrium (e.g., increased inflammatory cytokines or reduced HOXA10 expression).
Recent observational data, including studies on uterine peristalsis in frozen embryo transfer (FET) cycles (PMID 41400630), suggest that while myometrial and endometrial waves play a role in embryo positioning, the presence of a focal polyp may disrupt this natural contractility or create a hostile environment. While some randomized trials have shown improved pregnancy rates following the removal of polyps prior to intrauterine insemination (IUI), the evidence for asymptomatic polyps under 10 mm in IVF/FET patients remains less definitive. Nonetheless, Han and Munro (2026) suggest that for patients known to have polyps, polypectomy is often reserved for those where the lesion is likely to impede success or where AUB is present.
Therapeutic Paradigm: Hysteroscopic Polypectomy
Management strategies vary based on symptoms, size, and patient risk profiles:
- Expectant Management: This may be considered for small (<10 mm), asymptomatic polyps in premenopausal women. Data suggest a spontaneous regression rate of approximately 25%. However, postmenopausal patients should not be managed expectantly due to the higher risk of malignancy.
- Medical Management: The levonorgestrel-releasing intrauterine device (LNG-IUD) may reduce the risk of polyp recurrence and alleviate associated bleeding, but it does not treat existing polyps. It is generally considered a secondary or adjunct option.
- Surgical Management: Hysteroscopic polypectomy is the treatment of choice. The clinical trend has moved away from the operating room toward office-based hysteroscopy. This approach, utilizing miniature hysteroscopes and mechanical or bipolar electrosurgical tools, can be performed without systemic anesthesia. Research highlights that this reduces the socioeconomic burden on patients and decreases the risk of anesthesia-related complications while maintaining high patient satisfaction and procedural efficacy.
Expert Commentary
The primary challenge in managing endometrial polyps today is the “over-diagnosis” of asymptomatic, small lesions in reproductive-aged women versus the “under-management” of polyps in high-risk postmenopausal populations. The Han and Munro (2026) update clarifies that while TVUS is a gateway, clinicians should utilize office-based sonohysterography more aggressively to refine the diagnosis before proceeding to surgery.
A critical point of discussion is the management of the tamoxifen patient. Given the high rate of sub-epithelial changes and polyps in this group, any report of vaginal spotting must be investigated with high-resolution imaging and biopsy. Furthermore, we must address the cost-benefit ratio of polypectomy in the asymptomatic IVF patient. While the ‘pre-emptive strike’ of removing any focal lesion is common practice, we require more robust randomized controlled trials to determine if the benefit to live birth rates justifies the surgical intervention for very small polyps (<5 mm).
Mechanistically, the association between uterine contractility and polyps (as hinted in studies like PMID 41400630) warrants further exploration. If polyps induce abnormal peristalsis, their removal might restore a more favorable environment for implantation, beyond mere mechanical clearing of the cavity.
Conclusion
Endometrial polyps are a ubiquitous cause of abnormal uterine bleeding and a potential barrier to fertility. The evolution of diagnostic technology, specifically the integration of sonohysterography and office-based hysteroscopy, has transformed the patient experience from invasive hospital stays to efficient clinic visits. While the risk of malignancy is low in the premenopausal population, a high index of suspicion must be maintained for postmenopausal patients and those on tamoxifen. Future research should focus on the molecular markers of malignant transformation within polyps and the definitive impact of small polyps on assisted reproductive outcomes. Currently, targeted hysteroscopic polypectomy remains the cornerstone of care, balancing high therapeutic efficacy with the advantages of minimally invasive technology.
References
- Han MN, Munro MG. Endometrial Polyps. Obstetrics and gynecology. 2026-03-12. PMID: 41818771.
- Uterine peristalsis in frozen embryo transfer cycles: Clinical implications. Gynecol Endocrinol. 2026. PMID: 41400630.
- Munro MG, et al. The FIGO classification system (PALM-COEIN) for causes of abnormal uterine bleeding in non-gravid women of reproductive age. Int J Gynaecol Obstet. 2011. PMID: 21570066. (Historical Context)