Placental mosaicism and complications of pregnancy

Abstract

Timely diagnosis of chromosomal aneuploidies plays an important role in determining the proper approach to the management of pregnancy. This article outlines the current ideas on the likelihood of occurrence of obstetric pathology, depending on the number of cells with genetic aberration, especially in the placenta. Such obstetric complications include fetal growth retardation, premature birth, and some forms of preeclampsia. The article describes the prenatal examination techniques, which help obtain timely information about the development of the fetus and predict pregnancy complications, more specifically, non-invasive prenatal DNA screening as a new technique with its advantages and limitations, based on the analysis of DNA of placental origin. It also highlights other latest diagnostic tools that allow to get more accurate information about placental mosaicism and the development of pathology. We have reviewed publications over the past 10 years, which are devoted to the factors responsible for the formation of placental mosaicism, the prenatal diagnostic procedures required for an accurate diagnosis, and the likelihood of obstetric pathology in case of prolonged pregnancy complicated by genetic aberrations. Foreign studies confirm the direct dependence of the likelihood of obstetric pathology on the number of cells with genetic aber ration. In accordance with the above study results, it would be only right to note that placental insufficiency can be observed in any case of genetic aberration, especially if a large volume of cells is involved in the pathological process at an early stage of differentiation. In addition, the article discusses the issue of need of thorough prenatal diagnosis to prevent the development of pregnancy pathology, including the use of the latest technologies and minimizing invasive methods.