Infertility

Male infertility

By Michael Russell

Male factors are projected to produce about thirty percent of all infertility troubles and to contribute to them in another twenty percent. Whatever conventional wisdom may have to say about whose "fault" the problem is, figures indicate that the responsibility is split about equally between the sexes. Studies initiated by the National Institutes of Health at six universities are exploring the increased incidence of sexually transmitted diseases among the young and its impact on infertility. At greatest risk are those between the ages of 15 and 19, regardless of socioeconomic differences.

The production or quality of sperm may be affected by congenital and genetic abnormalities, injuries to the genital tract, heat, age, sperm agglutination, acute and chronic infection (often sexually transmissible infections), malnutrition, previous surgery, allergies, chronic illness, environmental or occupational factors (such as radiation), varicocele, or certain medications. Among these medications are Tagamet, used in ulcer treatment; drugs used for treating cancer; and some antibiotics (especially those used to treat tuberculosis). Also heavy smoking of marijuana, tobacco use, alcoholism, and stress may result in impotence or inability to ejaculate.

Varicocele, a varicose enlargement of the veins of the spermatic cord, is a potentially curable cause of male infertility. While this condition occurs in many men with normal fertility, it has been found to be present in as many as forty percent of infertile men. Half of all men with varicoceles have decreased sperm count or sperm motility or other changes in the semen analysis. Theories of the cause of these changes include heat, pressure and toxic substances from the dilated vessels.

Permanent or temporary damage to the male testis can occur as a result of a genital infection or a systemic infection. Gonorrhea may do enough damage to the male genital tract to result temporarily in a marked decrease in the sperm count. Mumps in an adult male may involve one or both testicles and may cause severe testicular damage. Fortunately, usually only one testicle suffers severe impairment and the sperm count, though possibly reduced, is usually compatible with fertility. Any systemic viral or bacterial infection may cause a temporary depression in the sperm count.

Because many of the infertility tests for women are more complicated and involve more risk than those for men, infertility testing often begins with the male. A semen analysis is a simple test that can provide a great deal of information. The male is asked to submit a recently ejaculated semen specimen to the physician or laboratory. This specimen is then examined microscopically to determine sperm count, their size and shape and if they are able to move normally. There is no sharp line of demarcation between fertility and sterility in the sperm count. Counts of less than 20 to 40million per cubic centimeter are often correlated with decreased fertility, although men with counts of 5 to 10 million have fathered children. A high percentage of sperm with abnormal shape, size, or decreased motility is also correlated with decreased fertility.

The semen can be analyzed also for antibodies and cultured for various infections. The hormone levels in the man's blood are also measured to make sure his hypothalamus and pituitary glands are functioning normally.