Abnormal uterine bleeding (AUB) is one of the most frequent complaints encountered in gynecological practice and represents a significant cause of morbidity among women of reproductive, peri-menopausal, and post-menopausal age groups. It has a substantial impact on a woman’s physical, psychological, and social well-being, often leading to repeated hospital visits and invasive diagnostic procedures. The burden of AUB increases with advancing age, particularly after 40 years, when the risk of underlying endometrial pathology also rises. Early and accurate evaluation of the endometrium is therefore essential to rule out premalignant and malignant conditions and to guide appropriate management. AUB accounts for nearly one-third of all gynecological outpatient consultations, and this proportion increases to approximately 70% in peri-menopausal and post-menopausal women.1 Furthermore, abnormal vaginal bleeding is responsible for nearly two-thirds of hysterectomies performed worldwide. Most gynecologists agree that abnormal uterine bleeding occurring after the age of 40 years warrants thorough evaluation to exclude endometrial polyps, hyperplasia, leiomyomas, or carcinoma of the endometrium.2 Histopathological assessment of the endometrium remains the cornerstone for diagnosing these conditions. Several methods are available for endometrial evaluation in women presenting with AUB. These include transvaginal ultrasonography, dilatation and curettage (D and C), hysteroscopy-guided biopsy, and office-based endometrial sampling techniques using devices such as Pipelle and Karman’s cannula.3,4 Among these, dilatation and curettage has traditionally been regarded as the “gold standard” for endometrial sampling.5 However, D and C is an invasive surgical procedure that requires hospital admission, operating theatre facilities, cervical dilatation, and general or regional anesthesia. Dilatation and curettage is one of the most commonly performed gynecological procedures and contributes significantly to hospital bed occupancy and operating room workload. Despite its diagnostic value, it is associated with several drawbacks including high cost, procedural discomfort, and potential complications such as anesthesia-related risks, uterine perforation, cervical injury, and intrauterine infection.6,7 Moreover, blind curettage may fail to sample focal lesions, reducing its diagnostic accuracy in certain cases.In view of these limitations, there is an increasing need for a simple, safe, accurate, and cost-effective outpatient procedure for endometrial assessment. Endometrial aspiration for histopathological examination has emerged as a minimally invasive alternative with good patient acceptability.8 Karman’s cannula is a soft, flexible suction cannula that can be introduced into the uterine cavity without cervical dilatation, making it ideal for office-based endometrial biopsy.9 It is inexpensive, does not require anesthesia or operation theatre facilities, and has a very low complication rate. Despite these advantages, endometrial aspiration using Karman’s cannula has not gained widespread acceptance for routine endometrial sampling.10 Therefore, the present study was undertaken to compare the diagnostic efficacy of endometrial histopathology obtained by Karman’s cannula with conventional dilatation and curettage in patients presenting with abnormal uterine bleeding. AIM To evaluate the accuracy of endometrial aspiration using Karman’s cannula for histopathological diagnosis in women presenting with abnormal uterine bleeding at a tertiary care hospital.

This prospective, comparative, hospital-based observational study was conducted in the Department of Obstetrics and Gynaecology at a tertiary care teaching hospital. The study was carried out over a period of 1yr, from jan 2024 to dec 2024. Women attending the gynecology outpatient department during routine working hours and presenting with abnormal uterine bleeding were screened for eligibility and enrolled in the study after obtaining written informed consent. A total of 126 women diagnosed with abnormal uterine bleeding were included in the study using a consecutive sampling method. Detailed history regarding age, parity, menstrual pattern, duration and amount of bleeding, and associated symptoms was obtained for each participant, followed by a thorough general, systemic, and gynecological examination. Relevant baseline investigations were performed as per hospital protocol. Endometrial sampling was first performed using Karman’s cannula as an outpatient procedure without anesthesia. The cannula was gently introduced through the cervical canal into the uterine cavity, and endometrial tissue was obtained using negative pressure. The sample was immediately preserved in 10% formalin and sent for histopathological examination. Subsequently, the same patient underwent conventional dilatation and curettage under anesthesia in the operation theatre. The curetted endometrial tissue was similarly sent for histopathological analysis. The histopathological findings obtained by Karman endometrial aspiration were compared with those obtained by dilatation and curettage, which was considered the reference standard. Women aged 40 years and above presenting with abnormal uterine bleeding were included in the study. Patients who were pregnant, had active pelvic infection, known bleeding disorders, cervical malignancy, or had already been diagnosed with endometrial carcinoma were excluded. Women who were unfit for anesthesia or refused consent were also excluded from the study. All collected data were entered in a predesigned proforma and analyzed statistically to determine the diagnostic accuracy, sensitivity, specificity, and predictive values of Karman endometrial aspiration in comparison to conventional dilatation and curettage.

TABLE 1: Age-wise Distribution of Patients Age group (years) Number (n) Percentage (%) <30 18 14.3 31–40 36 28.6 41–50 44 34.9 >50 28 22.2 Total 126 100 The majority of women with abnormal uterine bleeding were in the 41–50-year age group (34.9%), followed by those aged 31–40 years (28.6%). Extremes of age were less commonly affected, with 14.3% below 30 years and 22.2% above 50 years. TABLE 2: Parity Distribution Parity Number (n) Percentage (%) Nulliparous 14 11.1 Multiparous 86 68.3 Grand multiparous 26 20.6 Most women in the study were multiparous (68.3%), while nulliparous women constituted only 11.1% of cases. Grand multiparous women accounted for 20.6%, indicating a higher prevalence of abnormal uterine bleeding among women with increasing parity. TABLE 3: Clinical Presentation of AUB Type of AUB Number (n) Percentage (%) Menorrhagia 54 42.9 Metrorrhagia 22 17.5 Menometrorrhagia 32 25.4 Postmenopausal bleeding 18 14.2 Among the study participants with abnormal uterine bleeding (AUB), menorrhagia was the most common type, observed in 42.9% (54) of cases, followed by menometrorrhagia in 25.4% (32), metrorrhagia in 17.5% (22), and postmenopausal bleeding in 14.2% (18), highlighting the varied clinical presentations of AUB in the population. TABLE 4: Indications for Endometrial Sampling Indication Number (n) Percentage (%) Evaluation of AUB 108 85.7 Postmenopausal bleeding 18 14.3 Suspected endometrial pathology 34 27 The majority of cases underwent intervention for evaluation of abnormal uterine bleeding (85.7%, 108), while postmenopausal bleeding accounted for 14.3% (18), and suspected endometrial pathology was noted in 27% (34). TABLE 5: Histopathological Findings by Karman Aspiration and D&C Histopathology Karman Aspiration D&C Proliferative phase 83 85 Secretory phase 20 21 Pseudo-decidual reaction 1 1 Endometrial hyperplasia 9 9 Adenocarcinoma 4 5 Atrophic endometrium 3 3 Unsatisfactory tissue 6 2 Histopathological examination showed that the proliferative phase was most common (Karman 83, D&C 85), followed by the secretory phase (Karman 20, D&C 21), with endometrial hyperplasia (9 each), adenocarcinoma (Karman 4, D&C 5), atrophic endometrium (3 each), pseudo-decidual reaction (1 each), and unsatisfactory tissue samples (Karman 6, D&C 2), indicating comparable diagnostic yields between the two methods. Table 6: Statistical analysis of endometrial patterns obtained by Karman aspiration in comparison with D&C (n = 126) Endometrial pattern Sensitivity (%) Specificity (%) PPV (%) NPV (%) Accuracy (%) Proliferative phase 97.65 100 100 95.35 98.41 Secretory phase 95.24 100 100 99.06 99.21 Pseudo-decidual reaction 100 100 100 100 100 Endometrial hyperplasia 100 100 100 100 100 Adenocarcinoma 80 100 100 99.18 99.21 Atrophic endometrium 100 100 100 100 100 Endometrial pattern analysis revealed high diagnostic performance, with most patterns—including proliferative, secretory, pseudo‑decidual reaction, endometrial hyperplasia, and atrophic endometrium—showing 95–100% sensitivity, specificity, PPV, NPV, and accuracy, while adenocarcinoma demonstrated slightly lower sensitivity (80%) but maintained 100% specificity and predictive values, highlighting the reliability of the assessment methods.

Age-wise distribution showed that abnormal uterine bleeding was most prevalent in the perimenopausal age group of 41–50 years, accounting for 34.9% of cases. This was followed by women aged 31–40 years, who constituted 28.6% of the study population, indicating significant involvement of reproductive-age women. Patients above 50 years formed 22.2% of cases, reflecting the contribution of postmenopausal bleeding to the study cohort. Younger women below 30 years represented the smallest group (14.3%). Parity-wise distribution revealed that a large majority of patients with abnormal uterine bleeding were multiparous, comprising 68.3% of the study population. Grand multiparous women formed a significant proportion (20.6%), suggesting an association between higher parity and the occurrence of AUB. In contrast, nulliparous women accounted for only 11.1% of cases. The increased prevalence of AUB among multiparous and grand multiparous women may be related to cumulative hormonal exposure and uterine structural changes. These findings highlight the importance of endometrial evaluation in women with higher parity presenting with AUB. Nama A, Kochar S, Suthar N, Kumar A, Solanki K et al11 In our study, 100 women with a clinical diagnosis of AUB were included. The baseline characteristics such as mean age, mean parity, were 43.14 ± 10.44 years, 3.22 ± 1.55. The study population with abnormal uterine bleeding (AUB) was categorized based on the type of bleeding. Menorrhagia was the most common, observed in 54 patients, accounting for 42.9% of cases. Menometrorrhagia was seen in 32 patients, representing 25.4% of the study group. Metrorrhagia occurred in 22 patients, making up 17.5% of cases. Postmenopausal bleeding was noted in 18 patients, which was 14.2% of the population. This distribution indicates that excessive and irregular menstrual bleeding is more prevalent than postmenopausal bleeding in the studied cohort. The indications for undergoing endometrial evaluation in the study population varied according to clinical presentation and suspicion of underlying pathology. The majority of women, 108 (85.7%), underwent the procedure for the evaluation of abnormal uterine bleeding (AUB), reflecting its high prevalence as a clinical concern. Postmenopausal bleeding was the indication in 18 cases (14.3%), emphasizing the need to rule out malignancy or atrophic changes in this group. Additionally, 34 women (27%) were evaluated due to suspected endometrial pathology based on imaging or prior clinical findings. This highlights that multiple indications often overlap, as some patients with AUB may also have imaging findings suggestive of endometrial disease. Histopathological examination of endometrial samples obtained via Karman aspiration and D&C revealed that the proliferative phase was the most common finding, observed in 83 and 85 cases, respectively, followed by the secretory phase in 20 and 21 cases. Pseudo-decidual reactions were rare, seen in only 1 case in each group. Endometrial hyperplasia was identified in 9 cases in both methods, while adenocarcinoma was slightly higher in D&C (5 cases) compared to Karman aspiration (4 cases). Atrophic endometrium was noted in 3 cases for both procedures. Unsatisfactory tissue samples were more frequent with Karman aspiration (6 cases) than D&C (2 cases), indicating variability in tissue adequacy between the two methods. The diagnostic performance of Karman aspiration for different endometrial patterns demonstrated high reliability. For the proliferative phase, sensitivity was 97.65%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 95.35%, and overall accuracy 98.41%. The secretory phase showed a sensitivity of 95.24%, specificity 100%, PPV 100%, NPV 99.06%, and accuracy 99.21%. Pseudo-decidual reaction, endometrial hyperplasia, and atrophic endometrium all achieved 100% in sensitivity, specificity, PPV, NPV, and accuracy. Adenocarcinoma had a slightly lower sensitivity of 80% but maintained 100% specificity and PPV, with an NPV of 99.18% and accuracy of 99.21%. These results indicate that Karman aspiration is highly effective and reliable for endometrial evaluation. Tomar NS (2020) et al12 Endometrial aspiration biopsy had sensitivity of 92.3%, specificity of 100%, positive predictive value of 100% and negative predictive value of 99.56% for diagnosis of endometrial pathology while considering D and C gold standard. The sample adequacy of endometrial aspiration was 98.8% as compared to dilatation and curettage (98%).

The study concluded that abnormal uterine bleeding is most prevalent among perimenopausal and multiparous women, with menorrhagia being the most common pattern. Endometrial evaluation using Karman aspiration was found to be a safe, reliable, and highly accurate outpatient procedure, with diagnostic performance comparable to D&C, making it an effective alternative for assessing endometrial pathology.

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