The high frequency of somatic diseases, gynecological diseases, complications of pregnancy in patients with obesity is the backdrop for a violation of the processes of formation and functioning of the placental complex; mother diagnosed with obesity significantly higher rates of resistance uterine artery and umbilical artery; 1.5 times more likely to be diagnosed degenerative changes in the placenta; 3 times more often revealed polyhydramnios; according to the morphological study of placentas it noted a higher rate of cardiovascular, ischemic and inflammatory changes; and therefore, should be classified as obese pregnant women at high perinatal risk.