Male fertility

Prenatal screening Auditory defects Oncogenetics Male fertility Thrombophilia

In case of almost half of all infertile couples there is, on examination of the partner´s sperm, a low concentration of sperms (below 20 million of sperms per 1 millilitre of sperm) related to a low mobility of sperms – oligoasthenosperm (OAS) or to a complete absence of sperms – azoospermia

 However, even in serious defects of the man’s fertility it is possible to find under the microscope individual sperms with acceptable properties and put them into an ovum. This technique has an abbreviation ICSI. In the case of azoospermia, it is possible to obtain sperms by means of the operation of didymis. The abbreviations of the methods for operational acquisition of sperms are MESA, TESE.

In preparation of an infertile couple with the „male factor“ for the assisted reproduction (ART), it is necessary to exclude several relatively frequent causes with risk of transfer to the following generation:

  • Microscopic chromosomal examination directed to balanced translocation when a certain block of genes in the cell core is situated in a different place than usual. The carrier itself is not affected, but in the development of sperms this may be the origin of abnormal forms. The cause of defects of the men’s fecundity may as well be caused by changes in numbers of sex chromosomes X and Y. The most frequent defect of the sexu chromosomes is the Klinefelter syndrome caused by the odd chromosome X.
  • Examination of the most frequent mutations of the cystic fibrosis gene. In this disease the activity of all exocrine glands is compromised (e.g. pancreas, bronchial and sweat glands). In case of the most serious form of cystic fibrosis there are repeated periods of devastating lung inflammation, which markedly shorten the lives of the affected people. Azoospermia caused by a closure of (or by an inborn absence of) gonadal duct or serious oligoasthenospermia may be the only sign of a moderate form of this disease. If the partner is a carrier of the mutated gene (frequency of transmitters in our population is 1/29), then their descendant has a significant risk of developing a fully expressed disease. We use the methods of molecular genetics to examine the 33 most frequent gene mutations in cystic fibrosis in the population of the Czech Republic.
  • The examination of the gene loss (deletion) on the long arm of the chromosome Y with methods of molecular genetics. On the long arm of the chromosome Y there are three areas AZF (AZospermia Factors) – a,b,c, which regulate the sperms´ development. With the help of ART, it is currently possible for the men with deletion of Y chromosome to have children. However, it is necessary to expect that their sons will have the same mutation and they will be infertile. The daughters will probably be unaffected. In demonstration of the deletion of Y chromosome it is possible to discuss the pre-implantation selection of sex.