Novel finding of high density of activated mast cells in endometrial polyps

Clinical utility of office hysteroscopy following failed in vitro fertilization-embryo transfer: A retrospective cohort study

OBJECTIVE

Despite its widespread use, in vitro fertilization (IVF) outcomes are challenged by implantation failure, largely due to factors such as embryo quality and endometrial receptivity. In this study, we investigated the clinical effect of office hysteroscopy (OH) on the subsequent frozen-thawed embryo transfer (FET) in infertile women who experienced a failed IVF-embryo transfer (IVF-ET) cycle.

METHODS

We included 577 infertile women who underwent OH because of a history of failed ET between October 2019 and September 2021. During OH, visible endometrial polyps (EPs) were diagnosed and removed by curette or biopsy forceps; chronic endometritis (CE) was diagnosed by histopathology and immunohistochemistry and treated with oral doxycycline (0.2 g/d) for 14 days. According to the hysteroscopic findings and endometrial pathology with immunohistochemistry, patients were divided into three groups: group A (n = 161) had CE with or without EPs, group B (n = 156) had EPs only, and group C (n = 260) had no CE or EPs.

RESULTS

In the following FET cycle, the implantation rates were 47%, 51%, and 45% (P = 0.411); the clinical pregnancy rates were 56%, 62%, and 55% (P = 0.436); the live birth rates were 45%, 51%, and 42% (P = 0.205); and the miscarriage rates were 18%, 16%, and 22% (P = 0.497) in groups A, B, and C, respectively. There were no significant differences among groups (P > 0.05).

CONCLUSION

OH is helpful for diagnosis and treatment of abnormal intrauterine environment in women with a failed IVF cycle and further improves their pregnancy outcome in the following FET.

Different endometrial preparation protocols on first frozen-thawed embryo transfer outcomes after hysteroscopic polypectomy: A retrospective cohort study

OBJECTIVE

To evaluate the optimal endometrial preparation protocol for frozen-thawed embryo transfer (FET) following hysteroscopic polypectomy.

METHODS

This was a retrospective clinical cohort study involving 464 patients who underwent their first FET after polyp resection between January 2021 and July 2023. The cohorts were categorized into three groups: the natural cycle (NC) group (n = 139), the ovarian induction (OI) group (n = 117), and the hormone replacement therapy (HRT) group (n = 208).

RESULTS

In the initial unadjusted analysis, both NC and OI cycles exhibited similar pregnancy rates but were associated with significantly higher implantation rate (56.5%, 57.1% vs 42.0%, P < 0.001), clinical pregnancy rate (73.4%, 74.4% vs 57.2%, P = 0.001), and ongoing pregnancy rate (OPR; 67.6%, 63.2% vs 51.0%, P = 0.005) compared to the HRT group. Additionally, the three groups demonstrated comparable abortion rate (7.8%, 14.9% vs 10.9%, P = 0.299). After adjusting for potential confounders in the multiple logistic regression model, the HRT protocol resulted in a 54% significantly lower OPR compared to the NC protocol (adjusted odds ratio [aOR] = 0.46, 95% confidence interval [CI]: 0.28-0.77; P = 0.003). Meanwhile, the OPR difference between the OI protocol and the NC protocol remained insignificant (OI vs NC: aOR = 0.62, 95% CI: 0.35-1.12; P = 0.112).

CONCLUSION

The ovulatory-FET scheme (NC and OI) following hysteroscopic polyp resection displayed promising clinical outcomes compared with HRT-FET scheme. The regimen without exogenous estrogen administration should be prioritized for endometrial preparation protocol after polypectomy.

Guideline No. 447: Diagnosis and Management of Endometrial Polyps

OBJECTIVE

The primary objective of this clinical practice guideline is to provide gynaecologists with an algorithm and evidence to guide the diagnosis and management of endometrial polyps.

TARGET POPULATION

All patients with symptomatic or asymptomatic endometrial polyps.

OPTIONS

Options for management of endometrial polyps include expectant, medical, and surgical management. These will depend on symptoms, risks for malignancy, and patient choice.

OUTCOMES

Outcomes include resolution of symptoms, histopathological diagnosis, and complete removal of the polyp.

BENEFITS, HARMS, AND COSTS

The implementation of this guideline aims to benefit patients with symptomatic or asymptomatic endometrial polyps and provide physicians with an evidence-based approach toward diagnosis and management (including expectant, medical, and surgical management) of polyps.

EVIDENCE

The following search terms were entered into PubMed/Medline and Cochrane: endometrial polyps, polyps, endometrial thickening, abnormal uterine bleeding, postmenopausal bleeding, endometrial hyperplasia, endometrial cancer, hormonal therapy, female infertility. All articles were included in the literature search up to 2021 and the following study types were included: randomized controlled trials, meta-analyses, systematic reviews, observational studies, and case reports. Additional publications were identified from the bibliographies of these articles. Only English-language articles were reviewed.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

Gynaecologists, family physicians, registered nurses, nurse practitioners, medical students, and residents and fellows.

TWEETABLE ABSTRACT

Uterine polyps are common and can cause abnormal bleeding, infertility, or bleeding after menopause. If patients don't experience symptoms, treatment is often not necessary. Polyps can be treated with medication but often a surgery will be necessary.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Therapeutic Carbohydrate Restriction as a Metabolic Modality for the Prevention and Treatment of Abnormal Uterine Bleeding

Therapeutic carbohydrate restriction diets have been becoming increasingly popular over the years, resulting in dramatic weight loss and an improvement in metabolic disorders. Obesity, insulin resistance, and diabetes are the risk factors for many gynecologic morbidities such as uterine leiomyoma, endometrial polyps, and polycystic ovarian syndrome. There is evidence suggesting that the pathogenesis of cardiovascular disease is similar to that seen in many causes of abnormal uterine bleeding. We aim to explain how cardiovascular disease risk factor reduction with the use of therapeutic carbohydrate restriction may prevent and potentially treat these gynecologic disorders.

Clinical outcomes in women with endometrial polyps underwent conservative management

OBJECTIVE

To evaluate the regression rate of endometrial polyps (EPs) in a cohort of asymmetric women after conservative follow-up.

MATERIALS AND METHODS

In this retrospective cohort study, a total of 1006 women with asymptomatic EPs were treated with expectant management or hormonal drugs between June 1999 and May 2018. Four hundred forty-eight women (44.5%) were administered with hormonal medications and 558 women were managed expectantly (55.5%). Office hysteroscopy was performed to confirm the diagnosis and regression of EPs. Hormonal administration included oral contraceptives, progestin and cyclic estrogen/progestin regimen according to physicians' preferences. Clinical characteristics, including the patient's age, body mass index, parity, and type of conservative management were collected.

RESULTS

The mean observation time was 14.1 ± 18.5 months (range, 1-162 months). The overall regression rate of EPs in this cohort was 33.5%, 24.6% occurred after medication and 8.9% after expectant management. Patient age (<50 years) (p < 0.001), follow-up period (p = 0.005) and hormonal drugs used (p < 0.001) were significantly associated with EP regression. Twenty-four (7.1%) of the 337 EP regression patients later developed recurrent disease. Follow-up period (p < 0.001) and hormonal drugs used (p = 0.032) were closely related to polyp recurrence after initial regression. Nevertheless, multivariate logistic regression analysis revealed that hormonal drugs used was significantly associated with the regression (p < 0.001) and recurrence (p = 0.016) of EPs.

CONCLUSION

Women aged 50 or less are more suitable for conservative treatment for EPs. Hormonal drugs used could increase the incidence of EP regression.

The prevalence of endometrial polyp in women with tubal factor infertility is higher than male factor infertility: Is PID one of the causes of endometrial polyp?

AIMS

Previous studies have shown an association between chronic endometritis and endometrial polyps, and only one study in infertile women reported an association between tubal obstruction and polyps. This study aimed to compare the prevalence of endometrial polyps in two groups of women with tubal factor infertility and male factor infertility to assess if is there any association between tubal factor infertility and endometrial polyps.

METHODS

This case-control study was performed on infertile women. The case group included women with tubal factor infertility and the control group included all women with male factor infertility. In all patients, vaginal ultrasound was performed between days 8 and 12 of the menstrual cycle to diagnose endometrial polyp, its size, and number. Demographic and obstetrics variables were recorded. Patients underwent hysteroscopy and polypectomy and the diagnosis of the polyp was confirmed by pathology report.

RESULT

In the present study, 245 people participated in two groups. There was a statistically significant difference between the two groups in terms of demographic and obstetric characteristics like type of infertility, duration of infertility, and gravidity. The prevalence of polyps in the tubal factor group was higher than in the male factor group (63 [60%] vs. 12 [9.8%]), and this difference was statistically significant (p = 0.0001). In addition, the prevalence of chronic endometritis in the tubal factor group was higher than in the male factor group (19 [18.8%] vs. 4 [3.3%]), and this difference was statistically significant (p = 0.001).

CONCLUSIONS

In the present study, a strong association was observed between endometrial polyps and tubal obstruction, and considering that the most common cause of tubal obstruction is pelvic and genital infections, after confirmation with more studies, it may be possible to consider antibiotic treatment in these patients, especially in patients with recurrent polyps.

Mast Cell Activation Syndrome in COVID-19 and Female Reproductive Function: Theoretical Background vs. Accumulating Clinical Evidence

Coronavirus disease 2019 (COVID-19), a pandemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, can affect almost all systems and organs of the human body, including those responsible for reproductive function in women. The multisystem inflammatory response in COVID-19 shows many analogies with mast cell activation syndrome (MCAS), and MCAS may be an important component in the course of COVID-19. Of note, the female sex hormones estradiol (E2) and progesterone (P4) significantly influence mast cell (MC) behavior. This review presents the importance of MCs and the mediators from their granules in the female reproductive system, including pregnancy, and discusses the mechanism of potential disorders related to MCAS. Then, the available data on COVID-19 in the context of hormonal disorders, the course of endometriosis, female fertility, and the course of pregnancy were compiled to verify intuitively predicted threats. Surprisingly, although COVID-19 hyperinflammation and post-COVID-19 illness may be rooted in MCAS, the available clinical data do not provide grounds for treating this mechanism as significantly increasing the risk of abnormal female reproductive function, including pregnancy. Further studies in the context of post COVID-19 condition (long COVID), where inflammation and a procoagulative state resemble many aspects of MCAS, are needed.

Novel microarchitecture of human endometrial glands: implications in endometrial regeneration and pathologies

BACKGROUND

Human endometrium remains a poorly understood tissue of the female reproductive tract. The superficial endometrial functionalis, the site of embryo implantation, is repeatedly shed with menstruation, and the stem cell-rich deeper basalis is postulated to be responsible for the regeneration of the functionalis. Two recent manuscripts have demonstrated the 3D architecture of endometrial glands. These manuscripts have challenged and replaced the prevailing concept that these glands end in blind pouches in the basalis layer that contain stem cells in crypts, as in the intestinal mucosa, providing a new paradigm for endometrial glandular anatomy. This necessitates re-evaluation of the available evidence on human endometrial regeneration in both health and disease in the context of this previously unknown endometrial glandular arrangement.

OBJECTIVE AND RATIONALE

The aim of this review is to determine if the recently discovered glandular arrangement provides plausible explanations for previously unanswered questions related to human endometrial biology. Specifically, it will focus on re-appraising the theories related to endometrial regeneration, location of stem/progenitor cells and endometrial pathologies in the context of this recently unravelled endometrial glandular organization.

SEARCH METHODS

An extensive literature search was conducted from inception to April 2021 using multiple databases, including PubMed/Web of Science/EMBASE/Scopus, to select studies using keywords applied to endometrial glandular anatomy and regeneration, and the references included in selected publications were also screened. All relevant publications were included.

OUTCOMES

The human endometrial glands have a unique and complex architecture; branched basalis glands proceed in a horizontal course adjacent to the myometrium, as opposed to the non-branching, vertically coiled functionalis glands, which run parallel to each other as is observed in intestinal crypts. This complex network of mycelium-like, interconnected basalis glands is demonstrated to contain endometrial epithelial stem cells giving rise to single, non-branching functionalis glands. Several previous studies that have tried to confirm the existence of epithelial stem cells have used methodologies that prevent sampling of the stem cell-rich basalis. More recent findings have provided insight into the efficient regeneration of the human endometrium, which is preferentially evolved in humans and menstruating upper-order primates.

WIDER IMPLICATIONS

The unique physiological organization of the human endometrial glandular element, its relevance to stem cell activity and scarless endometrial regeneration will inform reproductive biologists and clinicians to direct their future research to determine disease-specific alterations in glandular anatomy in a variety of endometrial pathological conditions.

Endometrial polyps with increased plasma cells are associated with chronic endometritis in infertility patients: Hysteroscopic findings and post-polypectomy pregnancy rates

PURPOSE

The relationship between endometrial polyps (EPs), chronic endometritis (CE), hysteroscopic findings, and antimicrobial in infertility patients was determined.

METHODS

We retrospectively enrolled 115 infertility patients with suspected EPs who underwent office hysteroscopy. Patients were divided into 3 groups: 38 with increased plasma cells in EPs (group 1); 31 without increased plasma cells in EPs (group 2); and 46 without EPs (group 3). The 3 groups underwent hysteroscopy with or without polypectomies, and immediately thereafter, an endometrial aspiration biopsy (EAB) was performed. CE was diagnosed based on plasma cell infiltration in the non-polypoid endometrium obtained by EAB.

RESULTS

The percentage of CE was 68.4%, 32.2%, and 28.3% in groups 1, 2, and 3, respectively. CE was more frequent in group 1 than group 2 or 3 (P = .01 and P = .002, respectively). The number of polyps was higher in group 1 than group 2. After adjustment for age and assisted reproductive technology, antibiotic therapy was not associated with pregnancy (adjusted odds ratio, 0.44; 95% confidence interval, 0.05-3.57) in patients with EPs and CE.

CONCLUSIONS

Group 1 was associated with CE, and hysteroscopic findings were different from group 2. Antibiotic therapy after polypectomy for EPs with CE may not always be necessary.

Management of endometrial polyps in infertile women: A mini-review

Considerable disagreement exists regarding whether endometrial polyps should be removed before attempting natural pregnancy and before pregnancy via intrauterine insemination (IUI) or in vitro fertilization (IVF). Through a literature review, we obtained information on the impact of endometrial polyps and polypectomy on fertility outcomes. Several observational studies have suggested that women with unexplained infertility may benefit from endometrial polypectomy for a future natural pregnancy. A few studies reported benefits from endometrial polypectomy in infertile women who plan to undergo IUI. However, no strong evidence supports polypectomy as a way to improve the pregnancy rate in infertile women who plan to undergo IVF or polypectomy during controlled ovarian stimulation for IVF. Although no studies have defined criteria for the polyp size that should be removed in infertile women, clinicians should be aware that small endometrial polyps (<10 mm) sometimes regress spontaneously. Endometrial polypectomy is currently justified in patients with repeated IVF failure, but more studies are needed to verify that endometrial polypectomy itself will eventually increase the pregnancy rate. Although several mechanisms by which endometrial polyps exert a negative effect on fertility have emerged, there is no consensus about the proper management of endometrial polyps in infertile women. Therefore, the management of endometrial polyps should be individualized depending on the patient's situation and clinician’s preference.

New Opportunities for Endometrial Health by Modifying Uterine Microbial Composition: Present or Future?

Current knowledge suggests that the uterus harbours its own microbiota, where the microbes could influence the uterine functions in health and disease; however, the core uterine microbial composition and the host-microbial relationships remain to be fully elucidated. Different studies are indicating, based on next-generation sequencing techniques, that microbial dysbiosis could be associated with several gynaecological disorders, such as endometriosis, chronic endometritis, dysfunctional menstrual bleeding, endometrial cancer, and infertility. Treatments using antibiotics and probiotics and/or prebiotics for endometrial microbial dysbiosis are being applied. Nevertheless there is no unified protocol for assessing the endometrial dysbiosis and no optimal treatment protocol for the established dysbiosis. With this review we outline the microbes (mostly bacteria) identified in the endometrial microbiome studies, the current treatments offered for bacterial dysbiosis in the clinical setting, and the future possibilities such as pro- and prebiotics and microbial transplants for modifying uterine microbial composition.

Endometrial polyps: Pathogenesis, sequelae and treatment

Endometrial polyps are overgrowths of endometrial glands that typically protrude into the uterine cavity. Endometrial polyps are benign in nature and affect both reproductive age and postmenopausal women. Although endometrial polyps are relatively common and may be accompanied by abnormally heavy bleeding at menstruation. In asymptomatic women, endometrial polyps may regress spontaneously, in symptomatic women endometrial polyps can be treated safely and efficiently with hysteroscopic excision.

The nervous system and genomics in endometriosis

Endometriosis is a gynaecological disease that occurs in approximately 10% to 15% of women of reproductive age and up to 47% of infertile women. The presence of implants of endometrial-like glands and stroma outside the uterus, characteristic of this disease, induce a wide variety of symptoms, mainly pelvic pain and infertility. Women suffering from this condition experience great distress, which significantly affects their quality of life. Numerous studies attempting to decipher the pathogenic mechanisms of endometriosis have been conducted around the world, yet its aetiology still remains unknown. It is widely believed that in women with endometriosis, the endometrium has characteristic features that allow the formation of implants once fragments have entered the peritoneal cavity through retrograde menstruation. Furthermore, a strong genetic tendency to develop the disease has been reported among patients and first-degree relatives. Thanks to the recent technological advances achieved in genomics and bioinformatics, a number of studies have had the potential to analyse several aspects of the pathogenesis of endometriosis from a genetic perspective. Due to the recent identification of nerve fibres in the endometrium of women with endometriosis, research on the neurogenesis of the disease has increased in the past few years. However, the genetic aspects of nerve growth in endometriosis have not been analysed in depth and further research providing important insights into the mechanisms that mediate pain in affected patients has the potential to contribute substantially to the future management of the condition.

Macrophages in patients with recurrent endometrial polyps could exacerbate Th17 responses

Endometrial polyps (EPs) are outgrowths in the endometrium with unknown etiology. The fact that EPs can often recur after surgical removal suggests that EPs are not induced by random events but by continuous or recurrent processes in patients. We previously demonstrated that the risk of EP development was positively associated with overactive Th17 responses. However, the requirements of Th17 upregulation are yet unclear. Here, we recruited 26 women with symptomatic EP and 24 without EP, and peripheral mononuclear cells were harvested for the examination of circulating immunity. Compared to controls without EP, the patients with symptomatic EP presented significantly elevated levels of monocyte activation. The circulating monocytes from patients secreted higher levels of tumor necrosis factor (TNF), interleukin (IL)-1β, IL-6 and IL-23 directly ex vivo and with LPS stimulation. In memory CD4⁺ T cells, monocytes were not required for IL-17 expression, but the presence of activated monocytes significantly increased the secretion of IL-17. In naive CD4⁺ T cells, activated monocytes were required for significant IL-17 secretion and RORC transcription. Interestingly, the monocytes from EP individuals were significantly more potent in promoting Th17 differentiation from naive CD4⁺ T cells than the monocytes from controls. Furthermore, we showed that monocyte-mediated Th17 differentiation required the secretion of TNF, IL-1β and IL-6. Together, this study demonstrated activated monocytes supported Th17 inflammation in patients with EP.

CD4+ T cell imbalance is associated with recurrent endometrial polyps

Endometrial polyps (EPs) are localized benign overgrowths at the endometrium, with currently unknown aetiology and pathogenesis. Although symptoms of EP can be alleviated or resolved by hysteroscopic polypectomy, a significant fraction of individuals develop recurrent EPs after initial EP removal. In rare cases, EPs may also undergo malignant transformation. In-depth understanding of the mechanisms that are involved in EP development is urgently needed. Recent works indicate that dysregulations in the immune system participate in the development of a variety of symptoms, such as aging, obesity and hypertension, many of which are EP risk factors. Based on these discoveries, we investigated the cellular immune system in premenopausal women with and without EP. Compared to EP-free controls, the women with EP presented significantly higher RORC expression but unchanged TBX21 and FOXP3 expression in the circulating CD4⁺ T cells. When stimulated with PMA/ionomycin, CD4⁺ T cells from women with EP presented significantly higher interferon (IFN)-γ and interleukin (IL)-17 secretion, and lower transforming growth factor (TGF)-β secretion. Hysteroscopic polypectomy did not significantly alter the composition of CD4⁺ T cells, as the women with EP presented a similar upregulation of Th17 inflammation and a downregulation of regulatory T cell (Treg) response postoperatively. Notably, in women that developed recurrent EP, the CD4⁺ T cells presented higher preoperative and postoperative RORC, IFN-γ, and IL-17 expression, as well as lower postoperative FOXP3 and TGF-β expression, than hysteroscopic polypectomy-treated women without EP recurrence. These data demonstrated an association between CD4⁺ T cell imbalance and recurrent EP development.

Mast cell activation disease and the modern epidemic of chronic inflammatory disease

A large and growing portion of the human population, especially in developed countries, suffers 1 or more chronic, often quite burdensome ailments which either are overtly inflammatory in nature or are suspected to be of inflammatory origin, but for which investigations to date have failed to identify specific causes, let alone unifying mechanisms underlying the multiple such ailments that often afflict such patients. Relatively recently described as a non-neoplastic cousin of the rare hematologic disease mastocytosis, mast cell (MC) activation syndrome-suspected to be of greatly heterogeneous, complex acquired clonality in many cases-is a potential underlying/unifying explanation for a diverse assortment of inflammatory ailments. A brief review of MC biology and how aberrant primary MC activation might lead to such a vast range of illness is presented.

Surgical Management of Endometrial Polyps in Infertile Women: A Comprehensive Review

Endometrial polyps are benign localized lesions of the endometrium, which are commonly seen in women of reproductive age. Observational studies have suggested a detrimental effect of endometrial polyps on fertility. The natural course of endometrial polyps remains unclear. Expectant management of small and asymptomatic polyps is reasonable in many cases. However, surgical resection of endometrial polyps is recommended in infertile patients prior to treatment in order to increase natural conception or assisted reproductive pregnancy rates. There is mixed evidence regarding the resection of newly diagnosed endometrial polyps during ovarian stimulation to improve the outcomes of fresh in vitro fertilization cycles. Hysteroscopy polypectomy remains the gold standard for surgical treatment. Evidence regarding the cost and efficacy of different methods for hysteroscopic resection of endometrial polyps in the office and outpatient surgical settings has begun to emerge.

Cellular immune environment in endometrial polyps

STUDY OBJECTIVE

To investigate the immune environment of endometrial polyps (EPs).

DESIGN

Prospective case-control study.

SETTING

Teaching hospital and university research laboratory.

PATIENT(S)

Reproductive-age women undergoing hysteroscopy dilation and curettage for benign indications. Samples were collected from women with (n = 23) and without (n = 40) EPs.

INTERVENTION(S)

Endometrial samples were immunohistochemically stained with antibodies against mast cells (MCs) and regulatory T cells (Tregs).

MAIN OUTCOME MEASURE(S)

Tryptase+, chymase+, and c-Kit+ MCs and Foxp3+ Tregs were quantified in EPs and polyp-adjacent, polyp-distant, and control endometrium.

RESULT(S)

Densities of all MC types were highly significantly increased in EPs compared with adjacent, distant, and control endometrium. Chymase+ and c-Kit+ MCs were increased in density in adjacent compared with control endometrium. c-Kit+ MCs were also increased in distant compared with control endometrium. Foxp3+ Treg density was increased in EPs compared with distant and control endometrium and decreased in distant compared with control endometrium.

CONCLUSION(S)

This study provides novel insights into localized disturbances in the cellular immune environment within EPs consistent with EPs being inflammatory lesions associated with MC overactivity. Tregs are likely to be recruited to EPs in an attempt to suppress the inflammatory process due to the greatly increased presence of MCs. These immunologic disturbances are likely to be involved in the causation of abnormal bleeding and infertility in premenopausal women with EPs, and their role in the pathophysiology requires further research.

Sessile polyps and pedunculated polyps respond differently to oral contraceptives

Endometrial polyp is the lesion frequently found by hysteroscopy. The presence of endometrial polyp is associated with abnormal uterine bleeding and is probably associated with infertility. Until today, clinical guidelines for endometrial polyp remain elusive. The aim of this preliminary study was to estimate whether the shape of endometrial polyps affects the response to the treatment with an oral contraceptive (OC). We performed a retrospective case series study on 50 women diagnosed as endometrial polyps by hysteroscopy and managed by the administration of OC. Hysteroscopy was performed in the follicular phase of the menstrual cycle before medical treatment. Endometrial polyps were classified as pedunculated polyps (n = 25) or sessile polyps (n = 25). After diagnosis, OC was administered for 2-5 months (median 3 months) intermittently: To quantify the regression rate of lesions, the area index of endometrial polyps was assessed. In the study group, when comparing the efficacy of treatment with OC, there was a statistically significant difference in the regression rate between sessile polyps and pedunculated polyps (76% vs. 44%, p = 0.042). We conclude that sessile polyps are more sensitive to OC treatment than pedunculated polyps, implying usefulness of the hysteroscopic classification of the shape of polyps in the management of endometrial polyps.