Objective: To describe the distribution of abnormal uterine bleeding (AUB) type according to the polyp (AUB-P); adenomyosis (AUB-A); leiomyoma (AUB-L); malignancy and hyperplasia (AUB-M); coagulopathy (AUB-C); ovulatory dysfunction (AUB-O); endometrial (AUB-E); iatrogenic (AUB-I); and not yet classified International Federation of Gynecology and Obstetrics classification system in a medically underserved American inner-city population. Our secondary objective was to find an association between risk factors and type of AUB. Material and Methods: We conducted a descriptive cross-sectional analysis at our outpatient women's health clinic located in the Bronx, New York City, from November 2016 to December 2019. Results: Among 390 patients, the most common AUB type was AUB-L (n=185, 47.4%), followed AUB-P (n=100, 25.6%), AUB-A (n=55, 14.1%), AUB-0 (n=19, 4.9%), AUB-M (n=15, 3.8%), AUB-E (n=14, 3.6%) and AUB-I (n=2, 0.5%). Race was distributed as follows: Hispanic (68.2%), Black (25.9%), Caucasian (3.3%), and Asian (2.1%). Comorbidities included hypertension (36.4%), diabetes (15.6%), and thyroid disease (6.9%). The median age at diagnosis was significantly higher in AUB-M (59 years old, p<0.001), AUB-P (52.5 years old, p<0.001), AUB-E (51.5 years old, p=0.001) compared to AUB-L (46 years old). The median body mass index (BMI) was significantly higher in AUB-E (34.2 kg/m(2), p=0.048) and AUB-0 (32.6 kg/m(2), p=0.038) compared to AUB-L (30 kg/m(2)). Race was equally distributed among the AUB types. AUB-M (66.6%, p=0.002), AUB-E (57.1%, p=0.022), AUB-P (47%, p <0.001), and AUB-A (30.8%, p<0.001), had statistically significantly more cases of hypertension compared to AUB-L (28.1%). AUB-P (27%, p<0.001), AUB-M (26.6%, p=0.025), AUB-E (35.7%, p=0.001) and AUB-A (9%, p<0.001) had more patients with diabetes mellitus (DM) than AUB-L (3.3%). Conclusion: In an American population of medically underserved patients, the most common cause of AUB was leiomyoma and the most common race was Hispanic. Women with AUB-L were younger, with lower BMI, and with fewer cases of hypertension and DM when compared to other types of AUB.
