5.1. Definition. Epidemiology. Classification
Definition. Placental insufficiency is a term for morphological and functional placental dysfunctions (poor blood circulation), which leads to a reduction of the blood supply to the fetus, growth retardation, shortening of the genetically programmed period of intrauterine development (high risk of premature termination of pregnancy), disorders of adaptation, compensation, and protection from the mother-placenta-fetus system.
"Placental insufficiency" and "fetoplacental insufficiency" are synonyms, although not quite correct in their form and essence. Placental insufficiency (PI) is not an isolated abnormality of the placenta, but a sum of combined impairments in the mother-placenta-fetus system, in which there is a mutual influence of diseases or abnormalities carried out through the placenta. No matter from which side the pathologic factors act, first of all they cause pathological changes in the placenta and disrupt its basic functions (transport, tro-phism and metabolism). PI leads to intrauterine growth restriction (IUGR), often combined with hypoxia. PI is a pressing issue of obstetrics, perinato-logy and pediatrics. In the structure of perinatal losses up to 40% are associated with PI and IUGR. Low newborn body weight may be caused by ethnic and constitutional features, but the condition of a fetus and a newborn is not impaired, and does not indicate PI or IUGR.
Epidemiology. Most obstetric complications are caused by placental insufficiency.
The incidence of PI in miscarriage is 50-77%, in preeclampsia 32%, in pregnancy with concomitant extragenital disease 25-45%, in pregnant women after viral and bacterial infection over 60% of cases. Perinatal mortality