Object of the study: mycoplasma infection in pregnancy. Purpose of the study: determination of the role of mycoplasma infection on the mother-placenta-foetus system and grounds for pathogenetically conditioned ways of the correction of changes. Methods of the investigation: clinical-laboratory, clinical-instrumental, microbiological, biochemical, immunological, histomorphological and statistical methods. Theoretical and practical results: a necessity of examining women with pathology of pregnancy for the presence of causative agents of mycoplasmosis was proved. A symptom complex of the clinical-laboratory indices, which demonstrate the initiation of obstetrical complications in mycoplasma infection, was established. By the results of the conducted researches, a pathogenetically directed method of treating and preventing mycoplasma infection complications in pregnant women with the use of flavonoids was devised and introduced into the practice of obstetrical establishments. The efficacy of the author’stherapy for mycoplasmosis of pregnancy, which reduces the inpatient stay of pregnant women, decreases the number of obstetrical complications and perinatal morbidity with a resultant improvement of the demographic situation, was proved. Novelty: for the first time, the present work contains a complex assessment of the mother-placenta-foetus system in mycoplasmosis. A negative effect, produced by mycoplasmosis on the course and result of pregnancy was proved, a possible development of obstetrical pathology in infection with mycoplasma or ureaplasma was revealed. For the first time, higher levels of interleukin (IL) 10 and IL6, a percentage of CD4+, CD8+, CD21+, CD16+, O lymphocytes with their lower activity, and a decrease of the total antioxidant activity of plasma in mycoplasmosis of pregnancy were found out. For the first time, the specificity and degree of affection of the placenta structure in the women, who suffered from mycoplasmosis, were determined. For the first time, new, scientifically grounded methods for the treatment of mycoplasma infection in pregnant women and prevention of mycoplasmosis complications with use of fla-vonoids as immune response modifiers, antioxidants and an-timicrobial compounds were devised. Degree of introduction: results of the conducted researches were introduced into the work of the Woman’s Health Centre of the Kharkiv Station Railroad Hospital, a specialized clinical maternity home No. 5 of the City of Kharkiv, municipal health care establishment - maternity home No. 3 of the City of Kharkiv, female dispensary of Kharkiv City hospital No. 1, Ukrainian Research Centre of Obstetrics, Gynaecology and Reproductology of Kharkiv National Medical University, Kharkiv Regional Hospital, Poltava City Clinical Maternity Home. Theoretical propositions and practical recommendations are used in the pedagogical process at Departments of Obstetrics and Gynaecology Nos 1 and 2 of Kharkiv National Medical University, the Department of Embryology and Cytology of Ukrainian Medical Stomatological Academy (the City of Poltava). Sphere of application: medicine, obstetrics and gynaecology.