The procedure to retain proper carbon dioxide in the body with a hypercapnicator is the basis for the proposed way to prevent the severe forms of placental insufficiency (PI). A control group comprised 30 healthy women with physiological pregnancy. After termination of a 3-month course of preventive carbogen therapy in 65 pregnant women at risk for the severe forms of PI (a study group), there was valid evidence suggesting that the respiratory center functioned in the carbogen therapy regimen until delivery occurred. PI developed in 64.6% of cases in the study group using controlled respiratory trainings and in 100% in the same comparison risk group (n=154) employing traditional medical prevention; with carbogen therapy the severe forms of PI occurred 2-fold less frequently. The data of placental morphological examination along with a study of the markers of endothelial dysfunction, apoptosis, and cell proliferation supported and accounted for better outcomes when preventive carbogen therapy was performed.