SEVERE ASTHENOZOOSPERMIA - A STRUCTURAL AND FUNCTIONAL-STUDY

Ejaculates from 25 patients with severe asthenozoospermia (all spermat ozoa immotile or only non-progressively motile) were studied to identi fy individually the cause of impaired motility. Multiple tests were pe rformed, viz. light and electron microscopic studies and sperm functio n tests. An objective scoring was applied to both the routine and the functional analyses. Three categories of samples were identified: (1) necrozoospermia (n=9), where sperm viability was very poor; (2) struct ural tail abnormality as seen by light microscopy (n=4); and (3) ultra structural abnormality (n=12). In the last category, one case showed a bsence of dynein arms; this was associated with mitochondrial abnormal ities. Mitochondrial abnormality with normal tail components was obser ved in the majority (n=7) and accessory fibre abnormality in four case s. The scoring system revealed that, functionally, all samples were ab normal whereas routine analysis showed 15 samples to be subnormal and 10 to be abnormal, which indicates the need for functional analysis. B ecause of the multiple defects seen in these samples, there is a need for a battery of sperm function tests. This study indicates that mitoc hondrial defects are one of the causes that may account for the loss o f sperm motility in the patient population.