Background: This study was conducted to examine the risk factors for adnexal masses in females less than 45 years, study the distribution of different types of adnexal masses in the study population, and to identify risk factors for benign and malignant ovarian tumors and endometriosis. Methods: This was a hospital-based case control study conducted among 135 females of age less than 45 years who presented with sonographic evidence of adnexal masses to the Department of Obstetrics and Gynecology at SAT Hospital, Trivandrum, a government institution, after obtaining clearance from the institutional ethics committee and written informed consent from the study participants. Results: Oral contraception was found to be a protective factor (OR-.230, p-value = 0.022) in the development of different adnexal masses. Dysmenorrhea was also found to be a protective factor while applying logistic regression (OR -O. O22, p-value = .440). Early age of menarche was obtained as a risk factor independent of others (OR-10.448, p-value = 0.00). While analyzing the regularity of the cycles, it was seen that irregular cycles were a risk factor for the development of adnexal masses (OR-3.806, p-value = 0.001). Conclusion: Early age of menarche was found to increase the risk of adnexal masses 10 fold. Irregular cycles were also found to be a risk factor. While analyzing the protective factors, oral contraceptive use and dysmenorrhea were found to be protective. The idea of these risk factors will help in early screening and management of patients with adnexal masses, out of which a small proportion will be malignant masses.