Testicle Biopsy

Occasionally, a testicle biopsy may be performed in which tissue samples are removed under anesthesia. A biopsy is most useful for detecting obstruction in the transport system when sperm production looks normal but the count is low. The standard biopsy procedure requires incisions (called an open approach) and can be painful afterward. The procedure is valuable not only for diagnosis of infertility and predicting fertility treatment success, but it may also be used in some cases to retrieve sperm for fertility procedures. The use of needle aspiration, which is less invasive, is proving to be as effective in evaluating infertility as the open approach and may also be used to retrieve sperm for assisted reproduction techniques in some cases.

Urinalysis

A urine analysis is important when sexually–transmitted infections are suspected as a cause of infertility.

Imaging Techniques

Ultrasound imaging may be used to accurately determine the size of the testes or to detect cysts, tumors, abnormal blood flow, or varicoceles that are too small for physical detection (although such small veins may have little effect on fertility). A vasogram is an x–ray used in conjunction with an opaque liquid injected into the vas deferens to reveal an obstruction. A testicular biopsy and the sperm count together, however, are better initial diagnostic tools for this purpose. A vasogram is best used by surgeons before an operation to locate the blockage they are attempting to clear.

Varicocele

A varicocele is a varicose vein of the testicle found in 15% to 20% of all men and in 25% to 40% of infertile men. (A varicose vein is one that is abnormally enlarged and twisted.) Varicocele may partially obstruct the passages through which sperm pass. Studies also suggest that varicoceles may impair sperm quality through unknown mechanism.
Some experts believe that varicoceles may prevent the enzymes contained in the acrosome on the head of the sperm from initiating fertilization. It should be noted, however, that some evidence supports that idea that varicoceles play only an insignificant role in infertility. One eight–year study of men with and without varicoceles found no differences in sperm quality or in the ability to conceive.

What Causes Abnormalities?

Infertility can result from many different factors. The specific cause of sperm abnormalities cannot be established in most cases. It may be the end result of one or a combination of factors that include chronic illness, malnutrition, genetic defects, structural abnormalities, and environmental factors. Partial obstruction anywhere in the long passages through which sperm pass can reduce their sperm counts.

General Problems with Sperm Production and Quality

More than 90% of male infertility is due to low sperm counts, poor sperm quality, or both. In 30% to 40% of cases of sperm abnormalities, the cause is unknown. Abnormal sperm production is categorized by the following terms. oligospermia (less than 10 million sperm per cubic centimeter of semen), azoospermia (no sperm), dysspermia (low–quality sperm), or aspermia (no ejaculate). One study reported that fertilization rates were 71% for men with a single defect in sperm count, motility, or morphology (structure), 50% for a double defect, and 39% for triple defects. Although it has been thought that fertility and sperm quality decline after age 40, a recent study has reported that sperm number, structure, and motility (the ability to move) do not decline until beyond age 64.