Spermatozoal density, motility and morphology in fertile and in infertile couples: a mathematical correlation.

Spermatozoal density, motility and morphology were mathematically correlated in a series of 167 fertile and 198 infertile male patients in the hope that should a high correlation between these parameters exist, a study of spermatozoal morphology might be indicated mainly in patients with low density and motility. Density, motility and morphology in the fertile series were lower than in the potentially fertile one. Partial correlation coefficients between density-morphology and between motility-morphology were lower in the fertile series than in the infertile one. Higher correlation coefficients were found between density-motility and morphology both in fertile and infertile series. Only slight differences were found between non-lineal and lineal coefficients for the pair motility-morphology. The best adjustment between motility and morphology was achieved by means of a logarithmic function. The low correlation coefficients found between density-morphology and between motility-morphology lead us to the conclusion that a study of the morphology of spermatozoa cannot be avoided in any semen sample no matter how normal the density and motility may be.