We have identified patients among non-obstructive azoospermia (NOA) cases in whom spermatozoa could not be detected despite treatment, but intermittent ejaculatory spermatozoon was found in their follow-up. NOA was observed in the retrospective screening at a rate of 15.35% among infertile men (n = 1976/12,871), while non-obstructive intermittent azoospermia (NO-IA) was detected at a rate of 6.8% among NO-IA (n = 135/1976) and 1.1% among all infertile men (n = 135/12,871). Spermatozoon was identified in the form of cryptospermia or extreme oligospermia in 58.13 (13.6–92.3) weeks on average in n = 55/135 patients among NO-IA. Pregnancy and live birth were achieved at a rate of 43.6% (n = 24/55) and 29% (n = 16/55), respectively, in intracytoplasmic sperm injection. NO-IA was composed of a group with no genetic pathological diagnosis, with lower follicle-stimulating hormone, lutenizing hormone and clinical varicocele rates compared with those of NOA (<0.05) and higher testicular volumes and pathological scores (<0.05). A major activity was observed in total testosterone, lutenizing hormone, testicular volumes and the logistic regression of pathological scores (<0.05).