Introduction: Atypical uterine bleeding (AUB) is the most common and frequent presenting complaint in gynaecology outpatient department in all age groups, especially in perimenopausal women accounting for more than 70%.

Methods: Prospective analytical study conducted from January 2017 to December 2017 in perimenopausal women (45-55 years). Other age groups with AUB, isolated cervical or vaginal pathology, leiomyoma of other types, bleeding diathesis, medications associated with AUB and pregnancy related causes of bleeding were excluded. Endometrial tissue collected by dilatation and curettage (D&C), endometrial biopsy and hysterectomy specimens subjected to histopathological examination were analysed.

Results: Total 150 specimens were analysed in which 83 were endometrial samples and 67 were hysterectomy specimens. Majority were multiparous women 45-50 years presented with heavy menstrual bleeding and showed proliferative endometrium as the predominant pattern ( 30%). Other endometrial patterns were simple hyperplasia without atypia (23.33%), complex hyperplasia without atypia (4%), secretory endometrium (15.33%), disordered proliferative endometrium (3.33%), irregular ripening (7.33%), irregular shedding (2%), atrophic (5.33%), endometritis (1.33%), endometrial polyp (4%) and carcinoma endometrium in 2% cases. Hysterectomy specimens revealed 51 cases of combined endometrial and myometrial pathologies. Myometrial pathologies included submucosal leiomyoma -44.77% and adenomyosis -31.34% as the causes of AUB.

Conclusion: AUB is one of the commonest reasons for women to seek medical help in all age groups, especially in perimenopausal age. Gynaecologists should pay attention towards these abnormal bleeding patterns along with the evaluation of endometrial tissue for histopathological findings which showed wide variety of abnormalities.

Keywords: Atypical Uterine Bleeding (AUB); Endometrium; Perimenopause