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Urology Resources

Male Infertility

The male factor as a cause for subfertility is suspected when the couple has tried beyond 1 year and the wife has been evaluated to have normal reproductive organs and regular cycles. In 50% of these infertile couples, the problem is in the woman alone. In another 20%, it is in both the male and female. In the remaining 30%, the male factor is solely responsible.

Conception requires the meeting and fertilisation of a healthy egg by a healthy sperm. This requires the timely release of the ovum and deposition of semen in the vagina. The chance of any spermatozoon reaching the ovum is a function of their quantity, quality and ability to penetrate into the egg. Evaluation of the infertile couple should therefore involve the couple from the outset until an abnormality is uncovered. An abnormal sperm count is usually the earliest indicator of a male factor.

The production of spermatozoa requires normal levels of sex hormones. Production of sex hormones is principally regulated by the pituitary gland in the brain. Conditions that affect the pituitary gland may result in infertility, and sometimes impotence too.

Other causes of hormone imbalance include liver diseases and steroid medications. Defective spermatozoa production can also occur without any apparent hormonal imbalance. Many of these cases are due to genetic disorders.

Causes

Congenital/genetic
Chromosomal defects like Klinefelter's syndrome, Noonan's syndrome, congenital adrenal hyperplasia and absent testes are congenital causes. Undescended testes tend to also be defective functionally and are generally poor producers of spermatozoa.
Acquired
Sperm production can also be affected by previous chemotherapy, radiotherapy, drug abuse (eg. marijuana, heroine), certain medications (cimetidine, spironolactone, ketoconazole), previous trauma, chronic renal failure, cigarette smoking and excessive alcohol consumption.
Sperm production can also be affected by previous chemotherapy, radiotherapy, drug abuse (eg. marijuana, heroine), certain medications (cimetidine, spironolactone, ketoconazole), previous trauma, chronic renal failure, cigarette smoking and excessive alcohol consumption.
Finally, retrograde ejaculation of semen into the bladder can result in low sperm numbers being deposited in the vagina. This is commonly seen in diabetics.

Evaluation

After the history taking, a general physical examination including the scrotum is done. Next, a blood test for hormone assay and a semen analysis is taken. An inadequate volume usually suggests a blocked vas while an inadequate concentration of spermatozoa suggests impaired spermatozoa production. A complete absence of spermatozoa in the presence of small, poorly developed testes indicates primary testicular failure while a complete absence of spermatozoa in the presence of normal testes suggests vas obstruction, particularly when the hormone profile is normal.

If blockage of the vas is suspected, a transrectal ultrasound scan of the seminal vesicles and ejaculatory ducts is done; these structures would be distended if there is an obstruction of the ejaculatory duct. If these structures are normal, surgical exploration of the testes can be done to obtain a biopsy, harvest mature sperms for freezing and future assisted reproduction, and correct any blockage.

Management

Treatment can only be initiated after clinical assessment and laboratory investigations are completed.

Medication
If the hormonal assays are found to be normal, then supplements eg. vitamins or swiss oats may be tried for a few months. Coupled with this is the need for lifestyle change, especially cessation of smoking. Hormonal abnormalities, if identified, may need referral to an endocrinologist.
Varicocoele ligation
If a varicocoele is the only identifiable factor found, most urologists would advise surgery to ligate these big veins. This operation improves the semen quality in about two-thirds of men and may double the chance of conception. The reason for a non-improvement in a proportion of men may be because of co-existent defective sperm production in the testes. Hence, a testicular biopsy is also done at the same time to determine the state of the sperm-producing cells.
Surgical exploration of the scrotum
This is indicated if obstruction is suspected. Testicular biopsy can be carried out to assess the function of sperm production and vasography xray to rule out obstruction. Corrective procedures can then be carried out to unblock or bypass the site of obstruction.
Surgery for obstructed ejaculatory ducts
If ejaculatory ducts are confirmed to be blocked at its opening into the urethra, they are best dealt by transurethrally resection (called TURED). Under anaesthesia, the opening of the ejaculatory ducts is cut.

Retrograde ejaculation is more difficult to treat. If semen quality remains poor, spermatozoa can be retrieved from the urine voided immediately after ejaculation either for direct insemination or used in one of many assisted conception techniques. The urine needs to be rendered alkaline to avoid damage to the spermatozoa.