Evaluating the Infertile Male

By M. A. Fischer, MD FCFP FRCS(C)

Infertility affects approximately 15% of couples of reproductive age and is defined as the inability to become pregnant after one year of unprotected intercourse. Fertility depends on both the male and female partners and problems in either or both may result in difficulty getting pregnant. About 20% of fertility problems are due to male factors, 40% to female problems, 30% to problems in both partners while in some couples, no obvious problem in either partner can be identified. The goal of this article is to review the evaluation of the male partner as part of the complete evaluation of the infertile couple.

When a couple is faced with infertility, it is important for both partners to be evaluated, preferably simultaneously. It is frustrating for patients to await the evaluation of one partner, only to find out things are okay and then to start all over again with the other partner. Although infertility is defined as the inability to become pregnant after one year of unprotected intercourse, it is usually recommended for couples to begin evaluation as soon as they present with fertility concerns.

Fertility in men requires a normal hormonal environment and normal testicle function to allow for sperm production and delivery of the sperm to the egg for fertilization. The evaluation of male fertility consists of a review of past health and medical problems, a physical examination and some basic laboratory tests.

A man’s medical history can provide important clues to the potential causes of male sub-fertility. Childhood development and surgery, in particular testicle and/or penis surgery, may be a cause of low sperm counts or poor sperm delivery. Normal sexual development and passage through the various stages of puberty also provides important information about the hormonal development of a male. Illness and infection, including sexually transmitted diseases and urinary tract infections are important. Most common childhood illnesses do not affect male fertility, but mumps occurring after puberty can have a devastating effect on the ability of the testis to produce sperm. Similarly, injuries to the testis or torsion of the testis may often reduce sperm quality or result in a low sperm count. Certain types of surgeries may also affect the ability of the male to produce sperm or may cause transport of sperm from the testis to the penis to be abnormal. The most obvious one is having had a vasectomy but other types of surgery may also impair fertility.

Certain medications can affect the hormonal environment or can directly affect the production of sperm in the testis. Steroids, like those taken by body builders and also testosterone (male hormone) supplements have a profound negative effect on sperm production and may result in sterility. These effects are not always reversible after having stopped the steroids or testosterone; men are well advised to avoid these medications at all costs. Chemotherapy and radiation treatments can also injure the cells, which produce sperm in the testes. Patients are advised that smoking cigarettes and drinking excessive amounts of alcohol, often results in low quality sperm and difficulty getting pregnant. Exposure to certain chemicals may also affect sperm counts.

Previous experience in fathering children or difficulties in doing so may provide valuable information about possible causes or problems reproducing with the current partner.

An assessment of sexual function and intercourse timing is also important in the evaluation of the infertile male. Some men experience difficulty getting an erection or ejaculating due to an excessive amount of stress placed on them to "perform" at the right time of the month. On the other hand, some men with chronic medical problems such as diabetes or other illnesses may not be able to get an erection easily or may not be able to ejaculate normally.

Many couples do not understand that the timing of intercourse according to a women’s menstrual cycle is crucial for success in getting pregnant. A woman usually produces one follicle (egg) during her cycle and this egg is only receptive to sperm for a short period of time. If the couple is not having intercourse around this time of the month it will be almost impossible for them to conceive.

Finally, a review of all previous infertility evaluations and tests is important to establish a complete picture of the couple’s infertility assessment.

The physical examination will usually include a general analysis with careful attention being paid for signs of illnesses which may impair fertility. The initial exam is focused on identifying potential causes of impaired sperm production, such as excessive weight or body fat. Assessment of hair distribution, skin, signs of normal male development, body type and potential breast development concludes this part of the examination.

Examination of the testis is crucial in the evaluation of the infertile male. The patient should be examined in a warm room and in an upright position. The testes are palpated and an assessment of size and consistency is made. Normal testis volume is variable but should be greater than 15cc and should be approximately equal on both sides. The testis should also be slightly firm and not soft with no hard areas palpated. The epididymis, a sack like structure on the side of the testes should also be palpated to ensure it is present but not obstructed, tender or containing any masses. The vas deferens, the muscular tube that runs from the bottom of the epididymis to the prostate through the groin and carries the fluid containing the sperm, should be carefully examined. Some men may be missing part of the vas or may have had surgery or injuries inhibiting sperm transport to the prostate. The testicle cord should be palpated to assess for any abnormalities. A varicocoele or series of enlarged veins above the testis is one of the most common physical abnormalities and may be associated with reduced sperm counts. These veins are only identifiable with the patient standing upright and may require a deep breath (valsalva maneuver) in order for the veins to be identified. Lastly, a rectal exam may sometimes be included to assess the prostate and adjacent structures.

Some basic laboratory tests complete the evaluation of the infertile male. A semen analysis or sperm test plays a central role in the evaluation of the infertile male. Men are asked to abstain from ejaculating for 2 or 3 days before the specimen is collected by ejaculating into a sterile container. The test is then repeated a week or two later. It is preferable for the samples to be collected at the lab although it may also be collected at home provided it is brought to the lab in less than 60 minutes and kept at body temperature.

Standard semen analysis provides information about the volume, the pH (acidity), the concentration (number of sperm), motility (number of sperm moving) and morphology (shape) of the sperm. Semen volume is usually between 1.5 and 5 mL. Low semen volume may indicate failure to collect the entire specimen, abnormalities of ejaculation, blockage of the ducts or other problems with production of the ejaculate in the prostate and seminal vesicles.

Patients often focus on the "normal" values of a semen analysis. However, the "normal" values of a semen analysis do not reflect averages or median results of semen analysis in a given population of men. Rather, we know that men with a sperm count below 20 million sperm per mL are more likely to have reduced fertility. However, many men with sperm counts in this range are fertile. The same applies to motility and morphology. More recent data suggests that current "normal" values may not be entirely accurate, which further adds to the difficulty in interpreting and understanding semen analyses. While the semen analysis is one of the cornerstones of the evaluation of the infertile male, this test probably reflects the potential for a man to father children rather than determining a simple yes or no answer. Obviously if a man has no sperm in his ejaculate fathering a child will not be possible. In summary, the semen analysis cannot be viewed as a standalone test or as a measurement of fertility rather, it can be most useful in combination with other parts of the evaluation of the male partner.

Blood tests can provide important information about the levels of several important hormones vital to both normal sperm production and male fertility potential. These tests can provide information about the areas of the brain that are involved in sperm production, namely the hypothalamus and the pituitary gland, as well as the testes.

Certain men may require tests to rule out genetic causes of reduced sperm production or blockage of sperm from the testes. Men with sperm counts less than 5 million per mL or that have no sperm in the ejaculate due to a sperm production problem should have a karyotype test (looks at all 23 pairs of chromosomes for abnormalities) and also a Y chromosome deletion test (looking at the Y or male chromosome) performed. On the other hand, men with no sperm in the ejaculate due to a blockage of sperm from the testis to the prostate or who are missing part or all of the vas deferens should have a cystic fibrosis test (CFTR) test done to rule out this as a potential cause of an abnormal sperm count.

Other tests may be suggested based on the clinical situation. If a blockage of the reproductive tract is suspected, a transrectal ultrasound of the prostate may be needed. If an abnormality of the testis is detected, then an ultrasound may be needed. Your doctor may recommend a biopsy of the testis if there are no sperm in the ejaculate but the hormone levels suggest that sperm production should be normal.

The doctors evaluating each couple’s case of fertility are the best resources for discussing and understanding the basic evaluation of fertility. No two couples with fertility problems are alike so it is important that a thorough evaluation of both partners is done to ensure that correctable causes of reduced fertility are identified and treated.

ABOUT THE AUTHOR: Dr. M.A. Fischer is Assistant Professor, Division of Urology, Department of Surgery, Department of Obstetrics and Gynecology at McMaster University and he is Andrology Consultant for the ISIS Regional Fertility Centre in Toronto.