ABSTRACT
<p><b>OBJECTIVES</b>To evaluate the relationship between sperm apoptosis and male infertility.</p><p><b>METHODS</b>Percentage of apoptotic sperm (PAS) in spermatozoa of fertile and infertile men were tested by flow cytometry (FCM).</p><p><b>RESULTS</b>Sperm apoptosis had happened in all different people. PAS in fertile and infertile group was (4.28 +/- 1.66)% and (18.67 +/- 8.55)% respectively, and difference was significant between two groups (P < 0.01). There was negative correlation between PAS and semen volume, sperm density, percentage of forward motility, percentage of normal morphology (P < 0.01).</p><p><b>CONCLUSIONS</b>There was very close relationship between sperm apoptosis and male infertility. FCM used to test sperm apoptosis is rapid, accurate, objective and reliable to analyse sperm functions and male fertility.</p>