The Role of the Cytogenetic Examination of Couples and Abortive Material in Case of Missed Abortion
About the author:
Gontar J., Ilyin I., Parnitskaya O.
Type of article:
The article deals with reproductive losses and the role of the genetic component of this problem. As we know, the frequency of miscarriage in the population amounts to 20%. Currently, the greatest interest is genetic, immune, thrombophilic factors, which are the least understood. Genetic factors are chromosomal abnormalities of the embryo or fetus formed at the confluence of two parent cells with the presence of an unbalanced chromosome set. Group of patients who have in their anamnesis the reproductive losses require an individual approach, adjusted counseling and selection of the most effective measures to avoid repeated spontaneous abortions, especially if the dominant cause is the genetic factor. The aim of this study is determine the proportion of chromosomal abnormali- ties in patients with reproductive losses, as well as to establish the number of normal and abnormal karyotype in the study of abortive material that demonstrate the role of chromosomal aberrations in the process of stopping the development of the embryo. Primary data collection was held on the basis of cytogenetic laboratory of “Institute of Genetics Reproduction” (director – Ilyin I., PhD) and “Medical Center IGR” (director – Parnitskaya O., PhD ) in the period from 2009 to 2013. 862 patients were karyotyped for medical reasons by missed abortion. Also performed cytogenetic study of abor- tive material in terms of the 5-12 weeks of gestation (392 cases). For investigating of abortive material were select- ed chorionic villi. For the study of samples used a standard karyotyping or FISH (fluorescence in situ hybridization). This study considered the results of karyotyping 862 patients who applied for cytogenetic analysis because of spontaneous abortion or medical history, and in 27. 26% of cases (n = 235) were identified deviation of karyotype. Depending on the indications for karyotyping the group of patients was divided as follows: a survey with a history of missed abortion was 72,04% (n = 621); patients with the problem of recurrent miscarriage – 24,01% (n = 207); the abortion for medical reasons in connection with multiple malformations of the fetus – 3,95% (n = 34). For cytoge- netics of abortive material 392 samples received, wherein a standard karyotype was obtained in 60,46% (n = 237), the result of using the method of molecular cytogenetic (FISH) – 21,43% (n = 84). In 18. 11% of cases (n = 71) the result was not obtained due to the specifics of the investigated material. On the results of cytogenetic analysis was determined a normal set of chromosomes in 33,96% (n = 109). Abnormal karyotypes were represented by the fol- lowing anomalies: chromosomal nondisjunction (monosomy, trisomy, etc.) in the karyotype abortions amounted to 58,25% (n = 187), polyploidy (triploidy, tetraploids) – 5,92% (n = 19), unbalanced structural chromosomal abnor- malities – 1,87% (n = 6). As the results of cytogenetic analysis in 66, 04% of aborting the fetus was a consequence of chromosomal abnormalities. Missed fetus with normal karyotype can be caused by a variety of teratogenic effects, provoking point mutations, impaired formation of extraembryonic (chorion, fetal membranes), hormone imbalance jf the pregnant woman, the immunological factors, physiological characteristics of the uterine endometrium, the physical health of the woman, the presence of acute infectious diseases. But the importance of cytogenetic analy- sis can not be underestimated. Since in some cases produce biologically akin offspring is only possible through assisted reproductive technologies. In the conditions progression of reproductive disorders we need to convert scheme of counseling in primary and secondary infertility, while considering not only the physiological condition of the patients, but also their genetic status. The high frequency of chromosomal abnormalities among patients with fertility requires more attention from doctors of reproductive medicine. Peripheral blood cells’ karyotyping appears to be one of the most important steps in couple’s examination held before their enterance the in vitro fertilization program. This test is crucial for the calculation of risk of chromosomally abnormal child conceiving and subsequent choice of the most appropriate treatment approach involving additional diagnostic methods, e. g. preimplantation genetic diagnosis. This procedure allows to avoid the embryotransfer of aneuploid or chromosomally unbalanced embryos into the uterus what is extremely helpful in case of one of the parents is a carrier of balanced chromosomal aberrations or other abnormality. Knowing karyotype and information about the carriers of specific mutations for our ethnic group, we can create the most effective and individual treatment for fertile disorders.
karyotype, missed abortion, miscarriage, chromosomal abnormalities.
- Ворсанова С. Г. Хромосомные синдромы и аномалии / С. Г. Ворсанова Ю. Б. Юров, В. Н. Чернышов. – Ростов-на Дону, 1999. – С. 155-156.
- Зерова-Любимова Т. Е. Стандарты анализа препаратов хромосом человека (методические рекомендации) / Т. Е. Зе- рова-Любимова, Н. Г. Горовенко. – К., 2003. – С. 10, 16-18.
- Радзинский В. Е экстраэмбриональные и околоплодные структуры при нормальной и осложненной беременности / В. Е Радзинский, А. П. Милованов. – М.: Медицинское информационное агентство, 2004. – С. 33-48
- Сидельникова В. М. Привычная потеря беременности / В. М. Сидельникова – М.: Триада-Х, 2004. – 304 с.
- Bricker L. Types of pregnancy loss in recurrent miscarriage: implications for research and clinical practice / L. Bricker., R. Farquharson // Hum. Reprod. – 2002. – Vol. 17, № 5. – P. 1345–1350.
- Gersen S. L. The principles of clinical Cytogenetics / Steven L. Gersen, Martha B. Keagle. – New York : Springer, 2013. – P. 275-292.
- Gosden J. R. Chromosome analysis protocols / John R. Gosden. – Totowa, NJ 07512 : Humana Press, 2010 – P. 449-478. McKinlay Gardner R. J. Chromosome abnormalities and genetic counseling / R. J. McKinlay Gardner, L. G. Shaffer, G. R. Sutherland. – New York : Oxford University Press, Inc., 2012. – P. 377–402.
- Shaffer L. G. An International System for Human Cytogenetic Nomenclature / L. G. Shaffer, J. McGowan-Jordan, M. Schmid.– Basel : Karger, 2013. – P. 140.
- . Wayandt H. E. Human Chromosome Variation: Heteromorphism and Polymorphism / Herman E. Wayandt, Vijay S. Tonk. – New York : Springer, 2013. – P. 140.
Publication of the article:
«Bulletin of problems biology and medicine» Issue 3 part 1 (110), 2014 year, 73-77 pages, index UDK 575