CLINICALLY RELEVANT MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL CHARACTERISTICS OF THE INTACT AND SCARRED MYOMETRIUM
There is evidence that 30 to 80% of women after abdominal delivery can give birth through natural birth canals with a favorable outcome for the mother and fetus, however, there are no objective criteria that testify to the safety of such births. The study purpose was to comparative evaluate morphological and im-munohistochemical characteristics of intact and scar-modified myometrium to identify women at risk for uterine scar failure and the development of hypotonic bleeding in subsequent pregnancy. In 47 pregnant women morphological and immunohistochemical study of the lower uterine segment myometrium was carried out. 27 the samples are a tissue of lower segment of the uterus, modified by the scar, after previously suffering a caesarean section, and 20 samples of unchanged myometrium of incision on the uterus during the first caesarean section. The morphological study shows that the myometrium of the lower segment after the previous Cesarean section is significantly reduced in volume, the content of the fibrous component of the extracellular matrix of connective tissue increases. Reticular fibers surrounding the myocytes are poorly expressed. The formation of a scar on the uterus leads to a violation of the formation, the presence of which is necessary for the implementation of the ability of myometrium to reduce. Increases the content of mast cells and their ability to degranulation and significantly reduced the expression of α-smooth muscle actin. The increase in the number of mast cells indicates their participation in the pathogenesis of scar tissue formation. And the inability of myocytes to form a layer against the background of a decrease in the expression of α-smooth muscle actin leads to a decrease in the full-fledged contractile activity of myometrium.