Abnormal uterine bleeding [AUB] is one of the most frequent reasons for gynecological consultation across the reproductive, perimenopausal, and postmenopausal years. It affects quality of life through anemia, fatigue, restriction of daily activity, sexual discomfort, and repeated health-care visits, and it remains an important cause of diagnostic procedures and hysterectomy in routine practice [1-3]. The terminology used to describe menstrual abnormalities was historically inconsistent, which often created confusion in clinical communication and research reporting. To address this problem, the International Federation of Gynecology and Obstetrics [FIGO] introduced standardized systems for symptom description and etiologic classification, including the PALM-COEIN framework, which categorizes structural and non-structural causes of AUB [1,2]. This classification has improved uniformity in evaluation and has reinforced the need for targeted investigation based on age, symptom pattern, and risk profile. Although history, examination, laboratory tests, and imaging all contribute to evaluation, endometrial sampling remains a key component when endometrial pathology is suspected [3-6]. It is particularly important in women aged 40 years and above, in those with persistent or recurrent bleeding, in patients with ovulatory dysfunction, and in women presenting with postmenopausal bleeding or other risk factors for hyperplasia and carcinoma [4-7]. Endometrial biopsy is practical, relatively low cost, and highly informative in resource-constrained settings. Histopathological examination allows differentiation between normal cyclical endometrium, disordered proliferative changes, inflammatory lesions, hyperplasia, polyps, hormone-related alterations, and malignancy [4-6]. For this reason, biopsy-based assessment continues to hold a central role even in the era of advanced imaging and hysteroscopic evaluation. Several studies have shown that the histopathological spectrum of endometrial lesions in AUB varies with age, hormonal milieu, and referral pattern [7-12]. Functional patterns such as proliferative, secretory, and disordered proliferative endometrium are commonly reported in reproductive and perimenopausal women, whereas hyperplasia, atrophy, and carcinoma are more frequently encountered in older age groups and in women with postmenopausal bleeding [8-14]. This age-related shift highlights the importance of interpreting histopathological findings within the clinical context. Local data are valuable because disease distribution differs across populations, and institutional studies help clinicians refine decisions about sampling, surveillance, and timely intervention. In this context, the present study was undertaken to evaluate the histopathological patterns seen in endometrial biopsy specimens from women presenting with abnormal uterine bleeding at a tertiary care center in Amalapuram, Andhra Pradesh, India. The objectives of this study were to describe the age distribution and clinical presentation of women with AUB, to identify the frequency of various histopathological patterns in endometrial biopsies, and to examine the age-wise distribution of these patterns with emphasis on benign, premalignant, and malignant lesions.

Study design and setting. This hospital-based cross-sectional study was conducted at KIMS, Amalapuram, Andhra Pradesh, India, over a six-month period from September 2019 to February 2020. The study involved endometrial biopsy specimens received for histopathological examination from women presenting with abnormal uterine bleeding in the Department of Obstetrics and Gynecology and evaluated in the Department of Pathology. The study was designed to document the histomorphological spectrum of endometrial lesions in women with AUB using a biopsy-based diagnostic approach, which is widely recommended in routine gynecological practice [3-6]. Study population. Fifty consecutive women presenting with abnormal uterine bleeding and undergoing endometrial sampling during the study period were included. Women from reproductive, perimenopausal, and postmenopausal age groups were considered eligible if they presented with bleeding that was abnormal in amount, duration, frequency, cyclicity, or timing. Patients with obvious pregnancy-related bleeding, known cervical or vaginal causes of bleeding, previously diagnosed genital tract malignancy on treatment, or inadequate clinical records were not considered for inclusion. The age, presenting symptom, and relevant clinical details were obtained from case records and pathology requisition forms. Specimen collection and processing. Endometrial samples were obtained by biopsy or curettage as decided by the treating gynecologist according to clinical indication. All specimens were fixed in 10% neutral buffered formalin, processed by standard paraffin-embedding technique, sectioned at appropriate thickness, and stained with hematoxylin and eosin. When necessary, multiple sections were examined to improve representation of the specimen. Histopathological interpretation was performed using accepted morphological criteria for cyclical endometrium, disordered proliferative endometrium, hyperplasia, inflammatory lesions, polyp, hormone-related changes, atrophic endometrium, and carcinoma [4-6]. Data variables and classification. Bleeding patterns were grouped clinically as heavy menstrual bleeding, intermenstrual bleeding, polymenorrhea, menometrorrhagia, and postmenopausal bleeding. Histopathological findings were categorized as proliferative endometrium, secretory endometrium, disordered proliferative endometrium, endometrial hyperplasia without atypia, atypical endometrial hyperplasia, endometrial polyp, chronic endometritis, atrophic endometrium, pill endometrium or hormonal effect, and endometrial carcinoma. The etiologic interpretation of findings was aligned conceptually with contemporary FIGO terminology for AUB where relevant [1,2]. Statistical analysis. Data were entered into a spreadsheet and analyzed using descriptive statistical methods. Continuous variables were summarized as mean ± standard deviation, and categorical variables were expressed as frequency and percentage. Age-wise distribution of histopathological findings was cross-tabulated to identify trends across the different age groups. Because the study was intended primarily to describe the histopathological spectrum in a defined hospital sample, emphasis was placed on descriptive analysis rather than inferential modeling. The findings were then interpreted in relation to previously published clinicopathological studies on abnormal uterine bleeding [7-14].

A total of 50 women presenting with abnormal uterine bleeding were included in the study. The age of the participants ranged from 24 to 62 years, with the majority belonging to the 41–50 year age group [40.0%], followed by 31–40 years [32.0%]. Women aged above 50 years constituted 14.0% of the study population, while 14.0% were aged 30 years or younger. The mean age of the study participants was 42.8 ± 9.6 years. The demographic profile is shown in Table 1. Table 1. Age distribution of study participants [N = 50] Age group [years] n % ≤30 7 14.0 31–40 16 32.0 41–50 20 40.0 >50 7 14.0 Total 50 100.0 Heavy menstrual bleeding was the most common clinical presentation, observed in 44.0% of cases, followed by intermenstrual bleeding in 18.0%, postmenopausal bleeding in 14.0%, polymenorrhea in 14.0%, and menometrorrhagia in 10.0% of women. Most cases of postmenopausal bleeding were seen in women above 50 years of age. Histopathological examination of endometrial biopsy specimens showed that proliferative endometrium was the most common finding, accounting for 28.0% of cases, followed by secretory endometrium in 18.0% and disordered proliferative endometrium in 14.0%. Endometrial hyperplasia without atypia was identified in 12.0% of cases, while chronic endometritis and atrophic endometrium each accounted for 6.0%. Endometrial polyp was noted in 8.0% of cases. One case each of atypical endometrial hyperplasia and endometrial carcinoma was identified, representing 2.0% each. Overall, benign histopathological patterns predominated in the present study. The clinical presentation and histopathological spectrum are presented in Table 2. Among women aged 41–50 years, proliferative and disordered proliferative patterns were more frequently observed, whereas atrophic endometrium, atypical hyperplasia, and carcinoma were predominantly seen in women older than 50 years. The age-wise distribution of histopathological patterns is shown in Table 3. These findings indicate a predominance of functional and benign endometrial changes in perimenopausal women, with clinically significant premalignant and malignant lesions occurring in a smaller subset of older women. Table 2. Clinical presentation and histopathological patterns in women with abnormal uterine bleeding [N = 50] Variable Category n % Presenting complaint Heavy menstrual bleeding 22 44.0 Intermenstrual bleeding 9 18.0 Polymenorrhea 7 14.0 Menometrorrhagia 5 10.0 Postmenopausal bleeding 7 14.0 Histopathological pattern Proliferative endometrium 14 28.0 Secretory endometrium 9 18.0 Disordered proliferative endometrium 7 14.0 Endometrial hyperplasia without atypia 6 12.0 Endometrial polyp 4 8.0 Chronic endometritis 3 6.0 Atrophic endometrium 3 6.0 Atypical endometrial hyperplasia 1 2.0 Endometrial carcinoma 1 2.0 Pill endometrium / hormonal effect 2 4.0 Total 50 100.0 Table 3. Age-wise distribution of histopathological patterns [N = 50] Histopathological pattern ≤30 years 31–40 years 41–50 years >50 years Total Proliferative endometrium 4 5 5 0 14 Secretory endometrium 2 4 3 0 9 Disordered proliferative endometrium 0 2 5 0 7 Endometrial hyperplasia without atypia 0 2 3 1 6 Endometrial polyp 0 1 2 1 4 Chronic endometritis 1 1 1 0 3 Atrophic endometrium 0 0 0 3 3 Atypical endometrial hyperplasia 0 0 0 1 1 Endometrial carcinoma 0 0 1 0 1 Pill endometrium / hormonal effect 0 1 0 1 2 Total 7 16 20 7 50

The present study showed that abnormal uterine bleeding was most frequently encountered in the 41–50 year age group, which constituted 40.0% of the study population. This predominance of perimenopausal women is consistent with previous reports showing that AUB becomes increasingly common during the menopausal transition because of anovulatory cycles, fluctuating ovarian steroid levels, and progressive endometrial instability [7-12]. Similar studies have also identified the fourth and fifth decades as the peak period for endometrial sampling in women with AUB [8-12]. The mean age observed in this study further supports the view that perimenopausal women form a major diagnostic subgroup requiring careful endometrial evaluation. Heavy menstrual bleeding was the most common presenting complaint in the present series. This observation aligns with the clinical profile described in several studies where excessive menstrual blood loss was the dominant symptom prompting medical consultation and biopsy [3,7,10]. The symptom spectrum in AUB is broad, but the predominance of heavy bleeding in tertiary care cohorts underlines its clinical relevance because persistent blood loss is associated with anemia, reduced work capacity, and impaired quality of life [1-3]. Histopathological assessment revealed that proliferative endometrium was the most common pattern, followed by secretory endometrium and disordered proliferative endometrium. This predominance of benign functional endometrium has been documented in earlier biopsy-based studies and reflects the high burden of non-neoplastic causes of AUB, particularly in reproductive and perimenopausal women [7-12]. Disordered proliferative endometrium, which was also common in the present study, is often regarded as a morphological expression of prolonged estrogenic stimulation without adequate progesterone opposition and is therefore expected in women with ovulatory dysfunction during the perimenopausal period [7-10]. The concentration of proliferative and disordered proliferative patterns in women aged 41–50 years in this study is therefore biologically plausible and clinically meaningful. Endometrial hyperplasia without atypia accounted for 12.0% of cases, while atypical hyperplasia and carcinoma were identified in one case each. Although these lesions were infrequent, their detection emphasizes the diagnostic value of endometrial biopsy, especially in older women and in those with postmenopausal bleeding [4-6,13,14]. Atrophic endometrium was confined to women older than 50 years, which is in keeping with established evidence that postmenopausal bleeding can arise from a thin and fragile atrophic endometrium, but still warrants tissue evaluation to exclude occult premalignant or malignant disease [13,14]. The overall findings of this study indicate that benign histopathological patterns predominate in women with AUB, but clinically significant lesions are not negligible. In routine practice, histopathology remains essential for distinguishing functional endometrial changes from hyperplasia and carcinoma, guiding conservative treatment in benign conditions, and enabling timely intervention when higher-risk lesions are identified [4-6]. The present study therefore reinforces the continuing value of endometrial biopsy as a practical and informative investigation in tertiary care settings. Limitations This study was conducted at a single tertiary care center with a relatively small sample size of 50 patients, which restricts broad external generalization. The cross-sectional design provided a descriptive snapshot without longitudinal follow-up. Clinical, ultrasonographic, and hysteroscopic correlation was not incorporated. Some bleeding categories and histopathological subgroups contained very few cases, which limited detailed subgroup comparison and reduced the strength of age-specific interpretation.

This cross-sectional study highlights that most endometrial biopsy findings in women presenting with abnormal uterine bleeding are benign, with proliferative endometrium emerging as the most common histopathological pattern. Perimenopausal women formed the largest clinical subgroup, and heavy menstrual bleeding was the predominant presentation. The detection of endometrial hyperplasia, atypical hyperplasia, and carcinoma in a small but important subset confirms the value of routine histopathological examination, particularly in older women and in those with postmenopausal bleeding. Endometrial biopsy remains a simple, informative, and clinically relevant diagnostic tool for stratifying risk, guiding management, supporting early treatment decisions, and avoiding delay in identifying clinically significant endometrial pathology in everyday routine tertiary care settings.

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