[How to recognize and classify male infertility]

Infertility of the couple affects 19% of the general population, 4% of which are infertile. Almost 50% of infertilities are ascribable to the male partner. Male infertility is determined by a preliminary clinical and biological evaluation which consists of full examination of the semen, with sperm and spermocyte counts and cultures. Further examinations depend on the data provided by this evaluation. The causes of human infertility can be classified as follows: 1. Abnormalities of the spermatozoa which may be of testicular origin (defect of gonadal maturation, genetic of genic congenital anomalies, varicocele) or of post-testicular origin (acquired or congenital excretory obstacle to be located by surgery and treated whenever possible. 2. Abnormalities of seminal plasma (seminal infections, autoimmunization, isoimmunization). 3. Abnormalities of ejaculation (pathogenic or iatrogenic retrograde ejaculation, organic or psychic anejaculation). 4. Unknown cause requiring more sophisticated sperm examinations, such as microvideography of the flagellum, exploration of the acrosome and of nuclear maturation.