Postmenopausal bleeding (PMB) refers to any form of vaginal bleeding occurring in women after natural menopause. Approximately 4% to 11% of postmenopausal patients experience PMB, accounting for 5% of the gynecological outpatient visits [1]. As a common symptom in middle-aged and elderly women, PMB mainly originates from the cervix, vagina, and endometrium. The bleeding can last for more than 7 days, and the symptoms often recur [2]. PMB is clinically significant because it may serve as the clinical manifestation of various underlying pathological conditions, including benign lesions and malignant tumors, especially endometrial cancer [3]. Therefore, the diagnosis and evaluation of PMB are crucial. From a clinical epidemiological perspective, although the incidence of endometrial cancer in PMB patients varies to some extent due to factors such as region, race, and lifestyle, it generally remains at a relatively high level [4]. A systematic review and meta-analysis involving 40,790 patients from 129 independent studies indicated that approximately 90% of women with endometrial cancer exhibit PMB; among women with PMB, 9% are diagnosed with endometrial cancer [5]. Moreover, the prognosis of endometrial cancer is closely related to its clinical stage at diagnosis. Early diagnosis and prompt, standardized treatment lead to a 5-year survival rate exceeding 80%, whereas the 5-year survival rate for advanced-stage disease is less than 30% [6]. Thus, for patients with PMB, whether an early and accurate diagnosis can be achieved directly determines the selection of subsequent treatment plans and the ultimate prognostic outcome.

Dilation and curettage (D&C) is an invasive diagnostic technique that involves dilating the cervical canal and then using a curette to “blindly” scrape endometrial tissue for pathological examination, primarily used for evaluating endometrial lesions [7]. Its core principle is to obtain endometrial tissue samples through scraping, followed by pathological analysis to establish a definitive diagnosis. For a considerable period in the past, D&C had been widely applied in the diagnosis of patients with PMB and became a routine clinical diagnostic method due to its relatively simple operation and low cost [8]. However, since D&C is a “blind scraping” procedure, during the operation, doctors cannot directly observe the actual conditions within the patient’s uterine cavity and can only rely on experience and tactile feedback for the procedure. This often leads to a higher likelihood of missed and misdiagnosed cases during the diagnostic process [9]. Particularly for some focal lesions, D&C often fails to accurately obtain diseased tissue, leading to diagnostic discrepancies.

In recent years, with advancements in minimally invasive medical technologies, office hysteroscopy (OH), as a novel uterine cavity examination technique, has gradually been widely applied in the field of gynecological clinical diagnosis [10]. Compared with traditional D&C, OH offers a unique advantage of “direct visualization”. Through the lens of the hysteroscope, doctors can directly observe the overall condition within the patient’s uterine cavity, including the morphology, color, and thickness of the endometrium, as well as the presence of lesions such as polyps, fibroids, and adhesions in the uterine cavity, along with detailed information about the location, size, shape, and boundaries of these lesions [11]. This method of examination under direct visualization enables doctors to more precisely locate the lesion sites and directly perform biopsy sampling of suspicious lesion tissues during the examination, thereby significantly enhancing the accuracy and reliability of lesion detection [12]. Additionally, OH typically does not require general anesthesia. Patients remain conscious during the procedure, experience a short postoperative recovery time, and have a low incidence of complications. Moreover, the examination can be completed in an outpatient setting, improving patients’ healthcare experience and treatment compliance [13].

Despite the advantages of OH in diagnosing PMB, there remains a lack of direct comparative studies on its diagnostic efficacy compared with traditional D&C. When faced with PMB patients, clinicians still encounter some confusion and controversy regarding whether to choose OH or traditional D&C as the preferred diagnostic method, making it difficult to establish a unified clinical diagnosis and treatment protocol. Based on the aforementioned clinical context and research needs, this study selected 108 PMB patients who visited the gynecological outpatient clinic of our hospital from August 2023 to May 2025 as the research subjects and retrospectively analyzed their clinical data. The patients were divided into the D&C group and the OH group according to the different examination methods they received. This study meticulously recorded the detection rates of different types of uterine cavity lesions by the two examination methods and the incidence rates of adverse reactions associated with the two examination procedures to comprehensively evaluate their clinical application value. The aim was to clarify the strengths and weaknesses of OH and D&C in diagnosing PMB, providing clinicians with a reliable basis for selecting the most appropriate diagnostic approach for individual patients. This will improve diagnostic accuracy, reduce missed diagnoses, and ultimately enhance patient outcomes and quality of life.

PMB serves as a crucial warning signal for malignant endometrial lesions, and its accurate diagnosis directly influences treatment plans and the long-term prognosis of patients. In clinical practice, although traditional D&C has long been a routine method for diagnosing PMB, the issue of missed diagnosis of focal lesions due to its “blind scraping” nature has not been effectively resolved. OH, with its technical advantages of direct visualization and targeted biopsy, offers a new approach to overcoming this diagnostic bottleneck [20]. This study retrospectively analyzed clinical data of 108 PMB patients, using postoperative pathological examination as the “gold standard” to systematically compare the diagnostic efficacy, safety, and patient experience-related indicators between OH and D&C. The results demonstrated that OH significantly outperformed D&C in core efficacy indicators such as diagnostic accuracy, sensitivity, and specificity. It is critical to emphasize that this superior performance stems from OH’s ability to provide direct visualization, which enables precise lesion localization and targeted biopsy, thereby yielding specimens of higher diagnostic quality for pathological examination. The final diagnosis in all cases relied on histopathological confirmation, not on visual inspection alone. Moreover, OH was associated with a lower incidence of adverse reactions, higher patient satisfaction, and superior quality of specimens submitted for examination.

The most notable technical advantage of OH lies in its “direct visualization” characteristic, which fundamentally addresses the inherent flaw of the “blind scraping” procedure in D&C [21]. In this study, the diagnostic accuracy rates of OH for endometrial atrophy, hyperplasia, polyps, and other lesions all exceeded 90%, with the diagnostic accuracy rate for endometrial cancer reaching 87.5% and the missed diagnosis rate being less than 10%. In contrast, the diagnostic accuracy rates of D&C for most lesions were less than 60%, with the diagnostic accuracy rate for endometritis being only 33.33% and the highest missed diagnosis rate reaching 66.67% (for endometritis). The core reason for these discrepancies is that OH, through a 2.9 mm 0° hysteroscope lens, enables comprehensive observation of the morphological features, color, vascular patterns, and details of space-occupying lesions in the endometrial cavity under a clear visualization provided by distension with 5% glucose solution [22]. For example, endometrial hyperplasia manifests as diffuse or focal thickening, with an uneven surface, an increased number of glandular openings, and abnormal distribution. Endometrial cancer, on the other hand, presents as grayish-white, friable, irregular nodules or polypoid protrusions, with abnormally dilated and tortuous surface vessels [23]. These visual features allow physicians to directly identify the location, size, boundaries, and nature of the lesions, avoiding the “blind operation” in D&C that relies on “tactile sensation and experience”.

Furthermore, this study acknowledges the role of pre-operative transvaginal ultrasound in evaluating endometrial pathologies. Although all patients underwent ultrasound examination with measurement of endometrial thickness, retrospective analysis suggests that for patients whose pre-operative ultrasound indicated possible focal lesions, traditional D&C is more prone to missed diagnosis due to its “blind curettage” nature. In contrast, the direct visualization advantage of OH enables precise localization and targeted biopsy of such focal lesions, which may be a key factor contributing to the significantly higher diagnostic accuracy of the OH group compared to the D&C group in this study. Future research could be designed prospectively to systematically compare the diagnostic performance of OH and D&C in patients pre-classified by ultrasound into focal versus diffuse endometrial pathologies.

From an anatomical perspective, the uterine cavity is shaped like an inverted triangle. Endometrial tissues in areas such as the uterine horns and fundus are prone to being missed by the curette during D&C procedures. In contrast, OH can flexibly adjust the viewing angle through its lens, providing clear visualization of all regions within the uterine cavity. It can even detect tiny polyps or focal hyperplasia with diameters smaller than 5 mm [24]. Kaveh et al. [25] also demonstrated that OH combined with biopsy is the gold standard for identifying malignant changes in endometrial polyps, offering advantages in identifying minute polyps and focal hyperplasia. In this study, the diagnostic accuracy rate for “no abnormality” cases in the OH group reached 100%, with a false-positive rate of only 1.92% (1/52). This supports that direct visualization imaging technology can effectively distinguish between “physiological atrophy” and “pathological lesions”, reducing misjudgments of normal endometrial tissues. Among the eight patients with endometrial cancer in the OH group, seven were correctly diagnosed, while one was misdiagnosed as having endometrial hyperplasia. This misdiagnosis may have been due to atypical lesion morphology, such as ambiguous glandular atypia and inconspicuous stromal infiltration. Nappi et al. [26] found that some patients may have coexisting atypical endometrial hyperplasia and endometrial cancer. In their study, 37.5% of patients with atypical endometrial hyperplasia were postoperatively diagnosed with cancer. Such lesions may exhibit similar morphological features under OH, such as dense glandular structures and disorganized architecture, making it difficult to distinguish them solely through biopsy. A definitive diagnosis often requires postoperative total uterine pathology. Additionally, OH allows for targeted biopsy of suspicious lesions during the examination, as opposed to the extensive scraping in D&C. This not only improves the efficiency of obtaining diseased tissue but also avoids interference from normal tissue in pathological diagnosis [27]. In this study, the “excellent specimen rate” in the OH group reached 92.31% (48/52), significantly higher than the 58.93% (33/56) in the D&C group, directly reflecting the advantage of targeted sampling. The study by Di Spiezio Sardo et al. [28] confirmed that endometrial biopsy under direct OH visualization significantly improves sample adequacy (RR 1.13, 95% CI 1.10–1.17) compared to blind sampling and reduces the risk of missing endometrial cancer or hyperplasia (RR 0.16, 95% CI 0.03–0.92).

Diagnostic efficacy is a core indicator for evaluating the clinical value of examination techniques. The OH group exhibited significantly higher diagnostic accuracy (94.23%), sensitivity (94.00%), and NPV (40.00%) compared to the D&C group (46.43%, 43.40%, and 9.09%, respectively). It should be noted that in this study, both missed diagnoses and misclassifications of lesion type were grouped as FN for the purpose of calculating diagnostic accuracy metrics. This stringent classification was chosen to reflect a clinically conservative approach, as misclassifying a malignant lesion carries significant clinical consequences similar to a missed diagnosis. While this approach may lead to a more pronounced underestimation of sensitivity and NPV for D&C, particularly given its tendency for misclassification, it underscores the clinical superiority of OH in providing accurate lesion-specific diagnoses. Future studies may consider separate analyses for missed vs. misclassified lesions to further delineate diagnostic performance.

From a clinical perspective, high sensitivity indicates that OH can more effectively identify patients who are “truly diseased”, thereby reducing the rate of missed diagnoses. In this study, the OH group had only 3 FN cases (5.77%), whereas the D&C group had 30 FN cases (53.57%). Among the 30 FN cases in the D&C group, subsequent investigation revealed that the initial ‘blind’ procedure had completely missed 3 cases of endometrial cancer and 3 cases of endometrial hyperplasia. Furthermore, D&C misclassified an additional 4 cases of cancer as hyperplasia. These findings highlight a significant limitation of D&C, as its failure to detect or correctly classify these premalignant and malignant lesions can lead to critical delays in diagnosis and treatment. The prognosis of endometrial cancer is closely related to its diagnostic stage, and the high sensitivity of OH can assist clinicians in promptly capturing signals of malignant lesions, thus avoiding delays in treatment due to missed diagnoses. Meanwhile, the high specificity and high PPV of OH can reduce the risk of overdiagnosis and overtreatment. It is noteworthy that although the NPV in the OH group (40.00%) was higher than that in the D&C group (9.09%), there is still room for improvement. This relatively low NPV is primarily attributable to the high prevalence of endometrial pathology in the studied PMB population. According to the Bayesian principles of diagnostic testing, NPV is inversely influenced by disease prevalence; when prevalence is very high, the number of true negative cases is inherently small, which mathematically limits the NPV value. In clinical terms, this means that in a high-risk population such as symptomatic PMB patients, a negative test result should still be interpreted with caution and may warrant further investigation if clinical suspicion persists. This may be related to the extremely low proportion of “no abnormality” cases among patients with PMB. When disease prevalence is excessively high, the NPV is susceptible to influence. In clinical practice, it is necessary to combine OH with other diagnostic modalities, such as ultrasonography, to make comprehensive judgments and further optimize the diagnostic process.

In addition to diagnostic accuracy, safety and patient tolerability are also key for clinical acceptance [29, 30]. This study revealed a significantly lower overall adverse reaction rate in the OH group (3.85%) compared to the D&C group (17.86%). Moreover, no severe complications, such as uterine perforation, cervical laceration, or post-operative intrauterine adhesions, occurred in the OH group. From an operational perspective, D&C requires dilation of the cervical os using a cervical dilator to a size that allows the curette to enter, a process that is prone to causing cervical mucosal tears. Additionally, its blind scraping may lead to uterine perforation due to improper force application or abnormal uterine positioning. In contrast, OH only necessitates cervical dilation slightly larger than the outer sheath of the hysteroscope, which is significantly less extensive than that required for D&C. Furthermore, the direct visualization during OH enables real-time observation of the anatomical relationships between the cervical canal and uterine cavity, avoiding blind force application and fundamentally reducing the risk of mechanical injury [31]. OH also demonstrates significant advantages in hemorrhage and infection control. The incidence of intraoperative/postoperative bleeding in the D&C group reached 7.14% (4/56), primarily due to excessive endometrial trauma or vascular injury caused by blind scraping [32]. In contrast, targeted biopsy in OH results in only minimal localized trauma, and the continuous irrigation of the uterine cavity with distension fluid during the procedure reduces both bleeding and infection risks [33]. In this study, no intraoperative/postoperative bleeding occurred in the OH group, and the infection rate was only 1.92% (1/52), lower than the 5.36% (3/56) in the D&C group. Additionally, patients in the OH group reported a median pain VAS score of 4.00 (interquartile range: 2.00, 5.00), significantly lower than the 6.50 (5.00, 7.00) in the D&C group. Patient satisfaction reached 94.23% (49/52) in the OH group, far exceeding the 71.43% (40/56) in the D&C group. The minimally invasive, low-pain, and convenient nature of OH significantly enhances patient compliance with diagnosis and treatment, particularly among elderly patients with PMB, reducing their fear of invasive procedures and facilitating the clinical goal of “early diagnosis and early treatment” [34, 35, 36]. Furthermore, D&C lacks real-time assessment of intrauterine conditions. If suspected malignant lesions are identified during the procedure, the operation must be terminated, and further examinations scheduled, prolonging the diagnostic and therapeutic process. In contrast, OH allows for “diagnostic treatment” during the examination, such as the removal of small polyps or the separation of mild adhesions, enabling one-stop diagnosis and treatment and shortening patients’ healthcare journeys [37, 38].

Although OH demonstrates significant advantages in the diagnosis of PMB, its clinical application still faces the following limitations that require continuous improvement in practice. First, the equipment and technical thresholds are relatively high. OH requires specialized OH equipment and well-trained operators. The cost of equipment acquisition is substantial, and physicians require systematic training to independently perform the procedure, which may hinder its widespread adoption in primary healthcare institutions. In the future, a “tiered diagnosis and treatment” model could be implemented, wherein basic OH equipment is deployed in county-level hospitals, accompanied by enhanced technical training for primary care physicians to gradually expand the application of OH. Second, there are risks associated with distension media. OH relies on distension media to expand the uterine cavity. Excessive distension pressure or prolonged procedural duration may lead to excessive absorption of distension fluid, potentially causing water intoxication, particularly in elderly PMB patients with concurrent cardiac or renal dysfunction, where the risk is heightened [39]. In clinical practice, it is essential to strictly control distension pressure and procedural duration while closely monitoring patients’ vital signs to promptly identify and manage complications related to distension media [40]. Third, the diagnosis of certain special cases still requires adjunctive modalities. Although OH provides clear visualization of intrauterine lesions, its diagnostic value for cervical canal or myometrial pathologies is limited. A comprehensive assessment incorporating cervical cytology, human papillomavirus (HPV) testing, or ultrasonography is necessary for accurate diagnosis [41].

Through a systematic comparison of the diagnostic performance OH and D&C in the diagnosis of PMB patients, this study confirms that OH, with its technical advantages of direct visualization, targeted sampling, and a minimally invasive profile, significantly outperforms D&C in terms of diagnostic efficacy, safety, and patient experience. The high accuracy and sensitivity of OH effectively reduce the rates of missed and misdiagnosed cases, providing a reliable basis for the early diagnosis and precise treatment of PMB patients. However, it is essential to underline that the final diagnosis must be based on histopathological examination. Gross diagnostic impressions obtained through direct visualization alone are insufficient and potentially misleading. All clinicians should await pathology results before making definitive clinical decisions. Its low incidence of adverse reactions and high patient satisfaction enhance treatment adherence, thereby facilitating the optimization of PMB diagnostic and therapeutic strategies.

The data that support the findings of this study are available from the corresponding authors, upon reasonable request.

XZ: Developed and planned the study, performed experiments, and interpreted results; Edited and refined the manuscript with a focus on critical intellectual contributions. YZ, CL: Participated in collecting, assessing, and interpreting the date; Made significant contributions to date interpretation and manuscript preparation. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript. All authors have participated sufficiently in the work and agreed to be accountable for all aspects of the work.

This study was approved by the Ethics Committee of The First Affiliated Hospital of Soochow University (Approval No.: 2025-1052). The study was carried out in accordance with the guidelines of the Declaration of Helsinki. We secured a signed informed consent form from every participant.

Not applicable.

This research received no external funding.

The authors declare no conflicts of interest.