The thesis presents the theoretical generalization and new solution of the actual scientific problem of modern obstetrics and gynecology, namely the reduction of the frequency of obstetric and perinatal complications in pregnant women with disorders of nutrient and D-vitamin balance by the development and implementation of differentiated treatment-based prophylactic treatment features of the mother-placenta-fetal system. Existing scientific data on the relationship between nutrient-vitamin imbalance and obstetric and perinatal complications in modern conditions have been expanded. New scientific data on the importance of vitamin D deficiency in the development of dysbiotic and inflammatory vaginal processes before and during pregnancy have been obtained. Only 10.6 % of women of reproductive age were found to have normal vitamin D levels, 41.4 % - insufficiency, 48.0 % - deficiency, and 36.9 % severe deficits. In 20.0 % of women, at the stage of preconception and early pregnancy, there is a clinical and laboratory manifestation of varying degrees of magnesium deficiency: mild deficiency in 38.9 % of pregnant women; a moderate deficit of 18.9 %, a significant deficit of 11.7 % in the absence of a control group. The prevalence of use of balanced complexes of essential nutrients, vitamins, cholecalciferol at the preconception stage and in early pregnancy (10.7 % and 32.0 %) was established. The existence of a correlation between magnesium levels and 25 (OH) D in serum was proved - Spearman correlation coefficient ? = 0.912 with a direct strong relationship between the tested substrates (p <0.05). At the same time, patients with varying degrees of vitamin D deficiency showed no changes in parathormone secretion and abnormalities of calcium and phosphorus levels. Vitamin D deficiency significantly increases the risk of inflammatory diseases of the lower genital tract: colpitis OR = 5.53 [95 % CI 1.27-24.09], cervicitis OR = 3.03 [95 % CI 0.39-23.62]; dysbiotic vaginal processes OR = 6.83 [95 % CI 1.57-29.63], MC disorders OR = 1.92 [95 % CI 0.7-5.30], genital endometriosis OR = 1.56 [95 % CI 0, 34-7.08]. Vitamin D deficiency at conception and during pregnancy increases the risk of early pregnancy termination - RR = 3.33 [95 % CI 1.08-0.29], NNT 12.857 (p = 0.0417), RR deficiency anemia = 4,222 [95 % CI 1,76-10,14], NNT 6,207, microbiota abnormalities - RR= 3,294 [95 % CI 2,013-5,392], NNT 3,077, recurrence of BV RR = 4,296 [95 % CI 2,142-8,618 ], NNT 4.186 (p = 0.0001). The risk of late miscarriage in the absence of adequate correction of magnesium and vitamin D deficiency is observed 7.45 times more often than in pregnant women with adequate magnesium and vitamin D balance - RR 5,977 [95 % CI 1,756-20,34], NNT 8,037 (p = 0) , 0029), the threat of premature birth is 3.6 times more frequent (p = 0.0157). The highest frequency of PE was recorded in pregnant women who had nutritional-vitamin balance correction since the end of the first trimester of gestation (12.1 %) - RR = 4,337 [95 % CI 0,897-20,967] (p = 0.031), in the same layers of pregnant women with deficiency Vitamin D (? 20 ng / ml 25 (OH) D in serum) is at high risk of developing gestational diabetes - RR = 5,630 [95 % CI 1,669-18,995]. In this group of pregnant women the risk of operative delivery was 2 times higher than the indicators of the control group: RR = 2,023 [95 % CI 1,115-3,669], NNT 7,82 (p = 0,0258). A reflection of the vaginal microbiota is a premature rupture of the fetal membranes, which is observed in 62.5 % of cases of premature births with deficiency of vitamin D. Premature births occur in 10.3 % of observations, 76.2 % of them in pregnant women, whose correction is Vitamin balance has been maintained since the end of the first trimester of gestation. It is proved that the intake of vitamin-mineral complexes containing 400-500 IU of cholecalciferol does not provide prevention, and even more so the treatment of hypovitaminosis D. With a lack of vitamin D daily intake of 1000 IU and 2000 IU from the pre-gravid stage does not allow to reach the onset and during pregnancy levels of vitamin D. Differential use of cholecalciferol (from 4000 IU to 6000 IU) at the pre-gravid stage and during pregnancy with control and dose adjustment to reach a normal level of vitamin D (level 25 (OH) D (? 30 ng / ml) enables the prevention of obstetric and perinatal complications. The efficacy of the proposed differentiated personalized principle for the correction of vitamin D deficiency / deficiency in the proportion of patients with 25 (OH) D level in the third trimester of gestation is 78.7 % in the first trimester, and 86.7 % in the third trimester. Application of the differentiated personified principle of correction of vitamin-elemental imbalance allows to reduce the frequency of recurrence of vaginal dysbiosis by 5.0 times, early unauthorized termination of pregnancy in 100.0 % of cases, the frequency of gestational diabetes mellitus by 3 times, preeclampsia - by 14.9 times 3.65 times in the absence of cases of perinatal mortality, achieve prevention of premature spontaneous birth in 96.0 % of cases of threat of termination of pregnancy.
