Information Sheet: Male Fertility Factors

Although very few men are truly completely infertile, many different factors affect the extent to which intervention may become necessary for many men to become fathers. This article examines the following areas of concern:

• Medical history
• Environmental factors
• Physical or physiological abnormalities
• Marital or personal stress
• Intercourse-related factors

Medical History

In addition to the standard physician inquiry into the patient's general health, the fertility patient can expect investigation into past medical events involving the genitals and the surrounding area. Surgery on, or trauma to, the genitals can adversely affect fertility, even years after they occur. The same holds true for chemotherapy: although the damage to testicular tissue and the toxicity to developing sperm wear off over time, in some cases chemotherapy causes irreversible infertility. In some cases, even illnesses, such as mumps, can have a similar effect.

But medical treatment is not the only drug-related possibility that may account for male infertility: recreational drug use can impair sperm production. The drugs associated with such a condition include alcohol, depressants (such as Valium or narcotics), marijuana, stimulants (such as cocaine) or anabolic steroids. Even smoking has been linked to low sperm production, as well as to reduced sexual ability.

In a different vein, a positive history of pregnancy – with the current spouse or a previous partner – demonstrates that no genetic abnormalities account for the current situation, and the couple and treatment staff can save time by focusing on other diagnostic possibilities. By the same token, knowing what tests have already been performed by other providers can eliminate duplication of effort. (This is not always the case, since some commercial labs do not meet the standards that fertility specialists demand, and some test might need to be redone.)

Environmental Factors

Exposure to toxic chemicals, heavy metals, radiation or even prolonged heat can impair sperm production. Even a high fever in the two or so months preceding intercourse can throw off a man's fertility.

Physical or Physiological Abnormalities

The conditions in this category may result from any of the other factors mentioned above and below, or they may occur on their own.

Among the first investigations of the clinical staff is to ascertain whether the patient has completed puberty. Early or late puberty often points to general endocrine problems that affect more than just fertility. Additionally, some men marry young enough that puberty has yet to run its course.

Some problems, however, exist within the semen itself, and may account for fertility difficulties:

• Viscosity – Semen lacking certain important enzymes can become too thick for the sperm to move properly.
• Agglutination – The degree to which sperm cells clump together might indicate infection or the production of antisperm antibodies, which might be produced either by the man himself or by the woman. Either way, the cells' movement is impeded.
• pH – If pH is too high, infection is likely.
• Volume – Too little seminal fluid may indicate an obstruction or anatomical problem. Too much fluid may dilute the sperm cell concentration.
• Motility – The percentage of sperm cells that are moving directly affects fertility. The higher the percentage, the greater the likelihood of conception. 50% is usually considered the lower limit of normal.
• Concentration – The minimum concentration – the number of sperm cells per cc of seminal fluid – in normal semen is about 20 million per cc (most men have more than 50 million per cc).
• Linearity – The straightness or forward progression of the sperm is measured on a scale of 0-4, with anything more than 2 reflecting normal movement.
• Morphology – Sperm cells must have a specific shape to function properly. Improperly formed cells will be incapable or impaired in movement, viability or ability to penetrate the outer layer of the egg. Different scales exist for determining what constitutes a normal percentage of properly formed cells. In any case, by itself this measurement does not accurately reflect or predict fertility.

Additional anatomical problems can also account for impaired male fertility. One of the most prevalent conditions associated with male infertility is the varicocele, an abnormal dilation of veins in the spermatic cord. Although the direct cause is not certain, many researchers believe that a varicocele adversely affects sperm development by increasing the temperature in the scrotum.

Marital or Personal Stress

Although fertility itself may remain unaffected, strains in the couple's relationship can impede the husband's ability to induce or sustain an erection, which renders the health of the sperm moot. But the couple's relationship is not the only possible source of stress that can precipitate a similar result. Stress stemming from one's work (or lack thereof), health, other relationships or even current events can have the same effect.

Intercourse-related Factors

Whether caused by stress, age or some other factor, the inability to achieve or sustain an erection has an obvious effect on the ability to conceive.

But even a man with no erectile dysfunction or physiological problems is not guaranteed fatherhood if the frequency or timing of intercourse is inadequate. The frequency of intercourse should be at its peak around the time of ovulation: a minimum of once every 48 hours as ovulation approaches, but preferably once a day.

And while mastering the timing helps, another important factor in intercourse comes into play: lubrication. During foreplay, the vagina produces lubrication in anticipation of sex. Rushed intercourse, performance anxiety or other factors prevent lubrication. This makes intercourse painful. The couple can choose relaxation techniques or other sources of lubrication such as mineral oil or Astroglide®. The couple should avoid thicker lubricants such as petroleum jelly or K-Y Jelly®, which can trap sperm.

Ejaculatory dysfunction can also prevent conception. If ejaculation is delayed, premature or absent, the couple will become frustrated. Delayed or absent ejaculation can make intercourse painful, while premature ejaculation has obvious negative implications for both conception and satisfaction. The frustration that results in turn may cause the couple to reduce the frequency of their intercourse, which certainly hurts the chances of conception.

Summary

The possible causes of male infertility are numerous, but the discerning physician will determine which factors are most likely to account for a given man's seeming infertility. The investigation includes exploration of environmental factors, medical history, personal habits, sexual behavior and anatomical or physiological indicators.