The Four Factors of Male Fertility
For a woman to conceive, her partner must be able to make and ejaculate viable sperm. To accomplish this, a number of mechanisms must be in good working order. To make this discussion easier to understand and pinpoint potential sources of infertility we divide the male fertility equation into the following categories: pre-testicular, testicular, post-testicular, and ejaculatory processes. The interruption of any one of these four processes accounts for most of male fertility problems. There are a 15 to 20 percent of very rare conditions or disorders that cannot be diagnosed at this time.
Before covering each one of the fertility factors in depth, we will give you an overview of the four processes.
Pre-testicular Function (Hormones)
Disturbances in the hormonal system cause about 10 percent of male fertility problems.
The brain plays a key role in regulating the hormones that affect the development of sperm (spermatogenesis). The process begins when the hypothalamus (a part of the brain) emits a substance (gonadotropin-releasing hormone, or GnRH) that stimulates the pituitary gland, located at the base of the brain. The pituitary gland then emits LH (luteinizing hormone) and FSH (follicle-stimulating hormone). These stimulate testicular development and sperm production. LH also initiates the testicular production of testosterone hormone responsible for virility, male secondary sex characteristics, and the support of sperm production. (If you got through that, the rest will be a cinch!)
A number of conditions can interfere with the development and timely delivery of these hormones. When the system breaks down, low sperm production (oligozoospermia) or no sperm production (azoospermia) may result. If you have a pre-testicular problem, you may have a chance of responding to hormone replacement therapy.
Testicular Function
Testicular failure represents about 75 percent of male fertility problems.
To respond to hormone stimulation properly, the testicles, or testes, must be capable of producing sufficient, normal, motile sperm (spermatogenesis). To assess the testicular potential, we need to know if the testes descended into the scrotum on time; if they have been damaged by excessive heat, toxins, disease, or trauma; or if for some genetic reason they failed to develop normally. If the damage or failure is severe, nothing much can be done to improve testicular performance. And testes impaired by toxic substances may recover when the toxins are removed.
Post testicular Function
Tubal obstruction, including vasectomy, accounts for about 10 percent of male infertility.
The post-testicular system of ducts must be capable of storing and delivering the sperm. Sperm delivery system problems include obstruction or interruption of the tubes as a result of congenital malformation, disease, surgery, or trauma. Laser surgery and microsurgical techniques offer excellent chances for duct repair and restored fertility. Newer techniques allow the urologist to remove sperm directly from the testicle. These sperm can then be injected directly into the wife's eggs.
Ejaculatory Disturbance, Impotence, and Sexual Problems
Ejaculatory disturbances, impotence, and sexual problems may prevent you from delivering sperm to the wife's vagina. These disorders represent less than 10 percent of male fertility problems.
Premature ejaculation, delayed ejaculation, retrograde ejaculation and impotence may stem from surgery, medication, medical conditions or physiological disturbances which respond may respond to a corrective treatment.
Clues from the Past: Analyzing Your Lifestyle
Travel, Work, Hobbies, and Activities
We know that certain chemicals can adversely affect sperm development (spermatogenesis) and lower sperm counts. Long-term exposure to these chemicals can cause irreversible damage; however, removing the toxin can often restore fertility.
Accidental and medically prescribed exposure to large amounts of radiation to the gonads (to combat a malignant tumor, for example) can also impair sperm production. If the tissue damage is not extensive, however, some degree of fertility may regenerate.
We also know that excessive exposure to heat can interfere with sperm production. One reason that the sperm-producing testicles are located in the scrotum is to lower their temperature one or two degrees below the body's. Some jobs may overheat the scrotum for example, the foundry worker or the sedentary long-distance truck driver. Oligozoospermia in the wheelchair-bound paraplegic also may be due to excessive scrotal heat. Removal of the heat exposure will usually resolve this type of fertility problem.
If you travel frequently, you may not be able to have sex during your wife's fertile time of the month.
Drugs, Alcohol, and Cigarettes.
If you've smoked marijuana over a long period of time, your semen analysis may show lower sperm motility and higher incidences of abnormal sperm morphology. Both of these factors are critical for fertility. Though not conclusive, there is indication that some of the hundreds of chemicals in cigarettes may interfere with fertility by elevating the number of abnormal sperm forms.
We also know that central nervous system depressants such as barbiturates, heroin, and other narcotics cause impotence and ejaculatory disorders. If you stop using these drugs, usually these symptoms resolve themselves.
Chronic alcohol use can lead to impotence, poor sperm quality, and further complications from liver damage. If alcohol damages the liver, you may have elevated estrogen (female hormone) levels. When a man's female hormones become excessive, they suppress his sex drive and interfere with his sexual performance. If you stop drinking alcohol, these conditions may reverse provided the liver can recover.
Stress and Excessive Exercise
If you believe that your life-style is too emotionally or physically stressful, try cutting back. Run fewer miles, try to avoid emotional situations, and incorporate more relaxing activities into your schedule. Taking steroids to increase muscular mass will make you look powerful and strong but you may become temporally infertile as long as you continue to take those hormones.
Your General Health
Medical Disorders
A number of childhood and adult diseases can adversely affect fertility. Some of the changes are only temporary; for example, a high fever (over 102 degrees) may cause the scrotum to overheat and the sperm to die. Usually this type of problem resolves itself in a few months.
Some diseases, however, exert a more lasting effect. For example, cystic fibrosis, tuberculosis, and adult mumps can destroy vital testicular tissues and leave you permanently sterile. Sexually transmitted infections such as gonorrhea, chlamydia, syphilis, and ureaplasma, leave scar tissue caused by the inflammation produced. It can partially or totally block the sperm ducts. These infections are usually limited to the lower parts of the male genital tract, urethra, prostate, and seminal vesicles. Seldom does the infection travel further in toward the testicles. With the exception of prostatitis, which can be difficult to clear up, sexually transmitted infections will usually respond to antibiotics.
It's vital that your sexual partner also be treated for infection because you can pass the disease back and forth between you. As you'll learn later, sexually transmitted diseases produce far more devastating damage in their female victims.
Systemic diseases such as high blood pressure, colitis, diabetes, and hepatitis can deteriorate sperm quality and cause impotence and ejaculatory disorders. Sickle-cell anemia, most frequently found in people with black heritage, may also reduce sperm concentration. Insufficient thyroid hormone has also been linked with low sperm motility and other hormone imbalances.
Kidney problems may also affect fertility. Reports of breast disorders such as tenderness, soreness, and milky discharge or neurological problems characterized by visual disturbances, dizziness, chronic headaches, and/or seizures may lead to suspect multiple sclerosis, nerve damage, or a problem with the pituitary. Since the brain and the master pituitary gland are vital for maintaining the sex hormone balance, any interruption in their function can impair fertility
Surgeries
If you have no sperm in the semen (azoospermia), but have normally sized testicles and normal hormone levels, you probably have blockage in the ducts between the testicles and the penis. If a hernia repair or lower abdominal surgery is part of the medical history, I'd be suspicious that you had an accidental vasectomy (severing of the vas deferens or duct coming from the testis during surgery). A colon resection injury can cause both erection and ejaculation problems. If you've had bladder or prostate surgery, you may suffer from retrograde ejaculation.
If you've had surgery for the removal of an adrenal, scrotal, or pituitary tumor, an endocrine (hormone) imbalance may be the reason of infertility. Once they're correctly diagnosed, hormonal deficiencies often respond well to hormone replacement therapy.
Medications
We know that certain medications lower fertility by depressing sperm production or impairing sexual performance. For example, if you take high blood pressure medication (antihypertensives) such as reserpine, methyldopa, and guanethidine; or if you consume alcohol or narcotics, you may have difficulty maintaining an erection and suffer from ejaculation failure. In addition, these drugs can lower the sex drive. Hypertension is often treated with medications called calcium-channel blockers (Captopril, Vasotec, nifedipine). These medications appear to affect the ability of the sperm to bind to and fertilize the egg.
Cytotoxic drugs, anabolic steroids, cimetidine (Tagamet for ulcers), sulfasalazine, spironolactone, opiates, and colchicine all may cause depressed sperm production. We also know that antimalarials, tetracycline, amebicides, nitrofurantoin (for bladder infections), propranolol (Inderal), and barbiturates may cause fertility problems. If you take methotrexate for psoriasis or cancer, you may even suffer irreversible germ cell damage in the testes. Many of the drugs mentioned are generic; that is, they are the names for the basic chemical compounds. Often by simply altering your medication the doctor can restore your fertility.
Chemotherapy and radiation therapy for cancer may have irreversible effects on fertility. However, if some of the testicular germ cells remain intact, the sperm production may resume when treatment stops. Since every case is individual, you should check with your doctor about your particular situation.
Your Sexual History
Sexual Development
I also need to know about your sexual development. For example, if you had undescended testes, I need to know if and when you underwent surgery to correct the problem. If you had the surgery before you were six, the testes may be fine. Otherwise, cellular damage that impairs sperm production may have occurred. It's also helpful for me to know if you went through puberty exceptionally early or late (the normal range is nine to sixteen). Sometimes this clues me in to hormone problems.
Sexual Performance
If you have difficulty getting and maintaining an erection, I want to check your general health, the nervous system, the hormone levels, and your exposure to toxic chemicals or medications. Any one of these factors can cause physical impotence. if necessary, your doctor may want a second opinion from a psychologist, neurologist, or psychiatrist. I'll discuss more about treating impotence and erection problems in Chapter 8.
It's also helpful to know if you've previously fathered a child, or if your wife has had an abortion or miscarriage during her partnership with you. With this information I can establish that you were fertile at one time and begin looking for problems that developed since then. Repeated miscarriages also alert me to the possibility of a chromosomal or genetic problem with either the man or woman.
Your Family History
Since fertility problems often run in families, I need to know if your mother, father, brothers, or sisters have encountered any difficulties. For example, if your mother had a history of repeated miscarriages when she was pregnant with you, she may have taken a drug called DES. Knowing whether or not you were exposed to DES could help me determine if you're suffering from DES-caused testicular abnormalities. I also need to know if your family has a history of hormonal problems such as diabetes, hypothyroidism, or adrenal gland malfunctions. Adding your family history to other clues may help me decide on which areas to investigate more closely.