Cytogenetic analyses in infertile men

In order to assess the significance of chromosome abnormalities and polymorphic chromosomal variants in male infertility, the results of cytogenetic studies of 90 patients ( 32 azoospermic and 58 oligozoospermic men) were compared with those of 30 control fertile men in Estonia. Total chromosome alterations were revealed in 47.8% of infertile men. Major chromosomal abnormalities had a 10-fold increase (13.4%) in infertile males (15.6% in azoospermics and 12% in oligozoospermics) compared to the control group. In azoospermics, the most prevalent were sex chromosomal abnormalities ( 47, XXY)( 12%), whereas a Robertsonian translocation, t(13; 14) was found in one patient (3.1). In contrast, in the oligospermia group the most frequent abnormalities were autosomal (10%), of which 6.9% were translocations. Sex chromosomal abnormalities were found very rarely (1.7%). Incidence of chromosomal variants was high (38%), but similar in all groups. The most frequently observed polymorphisms involved chromosome 9. In conclusion, chromosomal abnormalities found with a high frequency in infertile males are a major cause of male infertility, and justify the requirement of cytogenetic analysis in every infertile man.