PREOPERATIVE SCREENING FOR GENETIC ABNORMALITIES IN MEN WITH NONOBSTRUCTIVE AZOOSPERMIA BEFORE TESTICULAR SPERM EXTRACTION

Purpose: Men with nonobstructive azoospermia may be treated with testi cular sperm extraction and assisted reproduction. However, in men with severely impaired spermatogenesis genetic anomalies may be a cause of low sperm production. We present the results of genetic screening of men with nonobstructive azoospermia who are testicular sperm extractio n candidates. Materials and Methods: Genetic evaluation was performed in a sequential series of 190 men with nonobstructive azoospermia who were candidates for testicular sperm extraction, including standard pe ripheral karyotypic analysis and detailed polymerase chain reaction ba sed evaluation of the Y chromosome. All men found to harbor genetic de fects were referred for genetic counseling. Results: Of the 190 patien ts 33 (17%) had genetic abnormalities. Of the 101 men who underwent ka ryotyping 21 (21%)had cytogenetic abnormalities, including 13 with Kli nefelter's syndrome. Of the 183 men who underwent Y chromosome partial deletion analysis defects were detected in 17 (9%). Five men had kary otypic anomalies as well as evidence of partial Y chromosome deletions on polymerase chain reaction based analysis. Genetic counseling was d one in 31 men with defects before testicular sperm extraction. Knowled ge of the specific genetic defect resulted in a change of clinical man agement in 7 of the 33 couples (21%) in which the man had a genetic ab normality. Conclusions: These results indicate that preoperative genet ic screening is important in men with nonobstructive azoospermia who a re candidates for testicular sperm extraction with intracytoplasmic sp erm injection. Genetic testing provides men with reassuring etiologica l information regarding the infertile condition as well as a means to assess the risk of passing infertility traits to male offspring. It al lows specific preimplantation genetic testing of embryos during assist ed reproduction to minimize the risk of transmitting genetic defects t o offspring.