Ultrastructural Abnormalities of Human Spermatozoa

The observation of sperm cells in the scanning and electron microscope reveals that malformed spermatozoa show either a single anomaly of each of their structural components--acrosome, nucleus, axoneme and accessory structures--or a combination of these anomalies. A defined semen profile can be established when the majority of ejaculated spermatozoa present a predominantly single anomaly or the same combination of associated anomalies. Only in these cases can there be a relationship between morphological defects and impairment of the fertilizing ability. The validity of the ultrastructural examination of sperm cells depends upon the data obtained by light microscopy, and quantification of the frequencies of the ultrastructural alterations is necessary to define clearly the limits of abnormality.