Breast cancer has a growing trend. The number of breast cancer patients in young women increases, associated with pregnancy. Cases of pregnancy-associated mammary gland cancer (CGMaS) and gestosis are increasing, requiring treatment and minimizing preoperative risks for surgical treatment in the first trimester of pregnancy. Material and methods. 12 patients with CGMaS and medium gestoses were included in the study. The patients were administered the medicinal remedy “Y”, studying the clinical and laboratory data in accordance with the Research Protocol, approved by the Ethics Committee. Statistical processing was performed using modern mathematical methods and the generally accepted statistical processing software “Statistical Package for the Social Sciences” SPSS 17 for Windows 10.0.5 (SPSS, Chicago, IL, USA) and “GraphPad PRISM® 5.0 for Windows 5.0 (GraphPad Software, Inc.). Results. Following the administration of the claimed method in patients with CGMaS and gestoses, the basic parameters improved - blood pressure normalized in 10 (83.3%) patients, pulse normalized in 11 (91,7%), nausea disappeared in 10 (97.3%), vomiting at 12 (100%), hypersalivation at 11 (91.7%), headache - at 11 (91,7%), sleep disturbances at 12 (100%), uterine tone at 12 (100%), low fever at 12 (100%), etc. laboratory indices also normalized at the same time. Conclusion. The use of the medicinal remedy “Y” in the treatment of early gestoses of moderate severity is effective through detoxification and confirmed by the improvement of the patients’ condition and laboratory indicators.