The objective: to study the incidence of gynecological diseases, clinical and hormonal parameters of the menstrual cycle in patients with benign hyper-plastic processes of breasts. Patients and methods. 65 women with various forms of mastitis were investigated. The following investigations were conducted: mammologistic and gynecological investigation, mommologistic X-ray investigation, ultrasound of breasts and of the pelvic organs, endometrial aspiration biopsy that was followed by cytology; when it was necessary the diagnostic laparoscopy, colposcopy, hysteroscope with curettage and morphological investigation of the endometrium, hormone research and rectal temperature measurements were conducted. Results. The frequency of the benign breast diseases was set: fibrocystic disease of breast – 32 women (49.2±6.20%), fibrous of breast – 16 women (24.6±5.34%), nodular of breasts – 8 women (12.3±4.07%), fibroadenoma – 6 women (9.2±3.59%), nodular disease of breasts on the background of fibroid changes – 3 women (4.6±2.60%). All in all, 96.9±2.14% of the patients had any gynecological diseases. Thus, the average age of the ‘debut’ of mastitis was 31.4±1.09 years; the hyper-plastic processes in the uterus was 35.2±1.17 years. Anovulation was detected in 17 (47.2±8.3%) patients, the lack of the luteal phase (NLF) was detected in 11 (30.6±7.6) patients. Conclusions. Identified hormonal changes are typical for patients with the hyper-plastic processes of the reproductive organs with different localization (breasts, uterus, ovaries). Due to the commonality of the hormone changes in most cases mastitis is combined with the various gynecological diseases (96.9±2.14%). Key words: gynecological pathology, hormonal changes, breast, factors of risk.