Modern Aspects of the Etiopathogenesis of Istmic-Cervical Insufficiency

Abstract

Isthmic-cervical insufficiency (ICI), which results in the failure of the circular muscles of the internal os, isthmus and cervix of the uterus is important in the pathogenesis of preterm birth. The existing types are anatomical, functional and congenital ICI. ICI is a pathological condition of the cervix and the isthmus, in which they are unable to withstand the intrauterine pressure and keep a fertilized egg in the uterine cavity until birth. ICI is a serious complication of pregnancy. Genetic, hormonal, inflammatory-infectious, immunological, traumatic factors play a role in the occurrence of ICI. The aim of the study is to study the peculiarities of reproductive health and gestational process of pregnant women with ICI, according to the literature. For the study, we analyzed domestic and foreign publications on this topic in professional journals, as well as data from Internet resources. Results of the research show that ICI plays a special role among many causes that lead to preterm termination of pregnancy and premature birth in the II-III trimesters. The properties of the cervix depend on the ratio of connective and muscle tissue. Today, most authors distinguish between congenital, acquired, organic and functional isthmic-cervical insufficiency.Organic (post-traumatic, secondary) ICI occurs due to mechanical damage to the cervix. Functional ICI is the result of a violation of the relationship between the muscular and connective tissues of the cervix, as well as the result of changes in the response of its structural elements to neurohumoral stimuli. Functional ICI most often occurs as a consequence of a violation of the hormonal background of women (ovarian hypofunction, hyperandrogenism). Congenital ICI occurs in malformations of the uterus, genital infantilism. Histological examination of cervical tissue in women with ICI reveals an increase in muscle tissue up to 50%, which leads to early softening of the cervix of the uterus and development of its functional insufficiency. According to Kaufman KP (2021), the role of connective tissue in the development of ICI is confirmed by the fact, that this pathological condition of the cervix is found in women with Marfan syndrome and Ehlers-Danlos syndrome. The role of undifferentiated connective tissue dysplasia (UCTD) as a risk factor for complicated pregnancy, including ICI.Research of Huang J and co-authors (2021) found the presence of nutritional imbalance in patients with UCTD, which was manifested by changes in serum concentrations of magnesium, calcium, zinc, iron, copper, selenium, inorganic phosphorus. The relationship between changes in the microcirculation system, tissue perfusion and cervical condition is currently being actively discussed and confirmed in numerous studies.Fettweis JM (2019) believes that the mechanism of abortion at different stages of gestation is not the same in pregnant women with ICI. At the same time, all pregnant women with ICI at all stages of gestation have increased cytokine levels. However, an important factor in the premature termination of pregnancy in ICI is assigned to the infectious factor. The results of the study of the pathogenetic role of local immune responses in women with habitual miscarriage are often contradictory and dictate the need for further researches.Eventually, isthmic-cervical insufficiency is a multifactorial complication of pregnancy, in which genetic, hormonal, inflammatory-infectious, immunological or traumatic factors play a role.