The influence of pathology of the thyroid gland in the mother on pregnancy course and state of a fetoplacental complex is investigated. Pregnant women with thyroid gland pathology more often have histosis, premature deliveries, gestation pyelonephritis, anemia, intrauterine growth retardation and hypoxia of a fetus. The frequency of operational deliveries is 2.5 times higher. The morphological studies of afterbirths have revealed presence of compensated chronic placental failure in hypothyroidism in mothers, sub compensated in hyperthyroidism, decompensated in hypothyroidism. Subcompensated and decompensated forms of chronic placental failure were accompanied by the signs of hypercoagulation in newborn umbilical cord blood.