Cytogenetic Investigations of Infertile Men With Low Sperm Counts: A 25‐Year Experience

Intracytoplasmic sperm injection (ICSI) is a providential therapeutic alternative for men with severe sperm count abnormalities.This method is being used increasingly and has given rise to numerous debates (Lamb, 1999;Schlegel, 1999).In fact, male infertility may be associated with several constitutional defects in genes and chromosomes (excluding Yq microdeletions).The existence of cytogenetic abnormalities in blood lymphocytes from infertile men has been reported in several surveys (Chandley, 1979;Croquette and Fourlinnie, 1980;Bourrouillou et al, 1985;Koulischer and Gillerot, 1985; De Braekeler and Dao, 1991;Yoshida et al, 1997).Most of these studies report wide frequencies of chromosomal anomalies, from 2.2% to 10.3%, due to different ascertainment procedures.Nevertheless, all of them point to an increasing percentage of chromosomal abnormalities concomitant with decreasing sperm count.In addition, the nature of chromosomal anomalies differs depending on whether a patient has oligozoospermia or azoospermia.In other respects, because cytogenetic investigative procedures are expensive and time-consuming, some authors (Pandiyan and Jequier, 1996) have aimed to determine the break-even point for the best cost:benefit ratio in the chromosomal survey of infertile men.In the present paper, based on cytogenetic findings in 2651 infertile men, we conclude that blood karyotyping should be performed on infertile probands when the sperm count is less than 5 million/mL. Patients and MethodsSince 1972, 13 154 men have been clinically examined and biologically investigated at the Centre de Ste ´rilite ´