FOLATE CYCLE: PATHOGENETIC MECHANISMS OF PREGNANCY COMPLICATIONS (REVIEW)

Abstract

The problem of prevention of complicated course of pregnancy and childbirth takes a leading place in modern obstetrics and perinatology. The authors conducted a profound analysis of numerous clinical studies in the area of folate metabolism in general, its role in the reproductive health of women, gestational complications, and the formation of fetal pathology. The significance of folic acid deficiency which is related to diet peculiarities, to insufficient enzymes intake, as well as to defects in folate exchange genes, which determine the reduced enzyme activity, is evaluated. In recent years, there has been much evidence that mutant homozygous (TT) and heterozygous (CT) genotypes are much more common among women with complicated pregnancies. Genetic deficiency of the key enzyme of the folate cycle – methylene-tetra-hydro-folate-reductase (MTHFR) is one of the reasons of hyperhomocysteinemia that has a pronounced toxic effect, damages the endothelial lining of the blood vessels and triggers a disorder of the processes of coagulation. Hyperhomocysteinemia has a big influence on the development of pregnancy complications, which depend on microcirculation, starting with spontaneous miscarriage in the first trimester of pregnancy and ending with preeclampsia, premature placental abruption and intrauterine fetal death. The consequences of the folate cycle problems at different stages can be congenital malformations of the fetus, especially defects of the neural tube. The importance of folic acid in the pathogenetic mechanisms of anemia is described. An interesting question is the role of low-functional alleles of folate genes in reproductive function disorders: under condition of infertility and miscarriage. The presented literature review is a reasonable conclusion for the need of further study of folate metabolism, taking into account genetic predisposition and other components.