https://www.selleckchem.com/products/ko143.html This article reviews the literature on placental morphofunctional changes in placenta of patients with type 1 and type 2 diabetes mellitus and gestational diabetes mellitus. The detailed analysis of features of pathogenesis of various abnormalities of the fetoplacental complex depending on the type of diabetes, its influence on the formation of the placental vascular bed. The analysis of mechanisms of development of placenta formation disorders, pathologies of placental vascular bed, the role of hyperglycemia and hyperinsulinemia in villous maturation, placental weight gain, perinatal outcomes. The discussed anomalies have a significant impact on the fetoplacental complex, acting as epigenetic factors, forming the environment for the fetus, which may later affect the health of the unborn child. They lead to adverse perinatal outcomes, including high infant morbidity and mortality. Literature search was performed in Russian (eLibrary, CyberLeninka.ru) and international (PubMed, Cochrane Library) databases in Russian and English languages. The free access to the full text of the articles was in priority. The selection of sources was prioritized for the period from 2016 to 2020. However, due to the lack of knowledge of the chosen topic, the selection of sources was dated from 2001.Aromatase excess syndrome (SIA) is a rare autosomal dominant disease caused by increased extraglandular conversion of androgens to estrogens. SIA is characterizedby early gonadotropin-independent hyperestrogenemia, causing pre-pubertal gynecomastia in boys and premature isosexual development in girls. Adults patients have short stature, due to the early closure of epiphyses because of hyperestrogenemia. Women usually have macromastia, endometrial hyperplastic processes and the late onset of menopause. In men, there is a moderate decrease of gonadotropins, leading to secondary hypogonadism. SIA in children can be suspected on a combination of the