Chromosome analysis of spermatozoa extracted from testes of men with non-obstructive azoospermia

Abstract

Infertile men with azoospermia now have the possibility of fathering a pregnancy by testicular sperm extraction combined with intracytoplasmic sperm injection. However, there are concerns about the risk of chromosomal abnormalities in their sperm. We have studied aneuploidy frequencies for chromosomes 13, 21, X and Y by multicolour fluorescence in situ hybridization (FISH) analysis in testicular spermatozoa extracted from three men with nonobstructive azoospermia. The men were 34-37 years of age and had normal FSH levels and normal 46, XY somatic karyotypes. A total of 3324 spermatozoa were analyzed. The infertile patients had an elevated frequency of disomy for chromosomes 13, 21, XY disomy compared to controls but none of these reached statistical significance. Also there was no significant difference in the sex ratio or the frequency of diploidy in azoospermic patients compared to normal control donors. This first report on chromosomal aneuploidy in spermatozoa extracted from testes of patients with nonobstructive azoospermia suggests that some azoospermic men do not have a substantially increased risk of chromosomally abnormal spermatozoa.