Male Infertility: Symptoms, Causes & Diagnosis

The inability to conceive a child can be stressful and frustrating, and although infertility affects almost 6.7 million couples in the United States (a staggering 10-11% of reproductive-aged couples in the United States), it is highly treatable in many cases.^[1][2]

The highly specialized field of male fertility involves a wide range of medical, environmental, and lifestyle causes which also includes many very specific risk factors. However, now that the genetic causes of male infertility are more commonly diagnosed, and several male infertility treatments are readily available, couples having difficulty conceiving or carrying to term, can often have success with the use of fertility medications.^[3]

Male Infertility Symptoms

As would be expected the main symptom of infertility (male or female) is the inability to conceive. Although there may be no other obvious symptoms, underlying problems such as hormonal imbalances, inherited disorders, or certain medical conditions in which the passage of sperm may result in telltale signs which include:^[4][5]

• Ejaculation difficulty
• Difficulty maintaining an erection (erectile dysfunction)
• Pain, swelling, or a lump in the testicle area
• Decreased facial or body hair or other signs of a chromosomal or hormonal abnormality
• A lower-than-normal sperm count
• A history of testicle, prostate, or sexual problems
• Groin, testicle, penis, or scrotum surgery
• Specific, and/or repeated trauma to the groin area

Understanding Male Infertility

Prior to discussing the causes of infertility, let’s examine the complex process of fertility from the male perspective. This process begins with properly functioning testicles, and the ability to produce testosterone as well as the supporting hormones which trigger and maintain sperm production.^[6][7] Once produced, delicate tubes transport sperm cells until they mix with semen and are ejaculated out of the penis.^[8] If the number of sperm in your semen (sperm count) is low, it decreases fertilization odds.^[9] Most authorities consider low sperm count to be fewer than 15 million sperm per milliliter of semen, or fewer than 39 million per ejaculate.^[10] In addition to production and volume, sperm cells must be shaped correctly and able to move freely.^[9][11] If the movement (motility) and shape (morphology) of your sperm is abnormal, it will experience difficulty reaching and penetrating the egg to complete fertilization.^[9]

Male Infertility Causes

Male infertility is most often due to three factors: 1) blockages that prevent the delivery of sperm; 2) low sperm count; and 3) misshapen or immobile sperm cells. However, because the process is so delicate, many related factors can also contribute to the overall problem including injuries, poor lifestyle habits, illnesses, and chronic health problems. More specifically, infertility causes are traditionally grouped into medical, environmental, and lifestyle categories among which are:^{[12][13][14][15][16][17][18][19][20][21][22][23]}

Medical Causes:

• Hormone imbalances can result from disorders of the testicles or an abnormality affecting the hypothalamus, pituitary, thyroid and adrenal glands causing a deficiency in testosterone production.^[24]
• Sperm duct defects – tubes that carry sperm can be damaged by illness or injury. Other transport problems include a blockage near the epididymis, cystic fibrosis, and genetic conditions which cause males to be born without sperm ducts.^[25]
• Bacterial and viral infections can cause scarring that blocks the passage of sperm, and may result from STDs including chlamydia and gonorrhea, or from inflammation prostatitis and mumps orchitis.^[26]
• Chromosome defects can cause abnormal development of the male reproductive organs and infertility. They include Klinefelter’s, Kallmann’s, Young’s, and Kartagener syndromes.^[27]
• Antibodies that attack sperm are immune system cells that mistake sperm for harmful invaders and attempt to eliminate them.^[28]
• Tumors can affect the male reproductive organs or the glands that release hormones related to reproduction.^[25][26][29]
• Undescended testicles^[25]
• Problems with sexual intercourse such as painful intercourse, anatomical abnormalities like hypospadias, difficulty maintaining an erection (erectile dysfunction), premature ejaculation, and psychological or relationship problems.^[30]
• Certain medications which include anabolic steroids, testosterone replacement therapy, chemotherapy, and certain antifungal medications.[^31]
• Varicocele – a swelling of the veins that drain the testicle, and may prevent normal testicular cooling, resulting in sperm abnormalities and lowered sperm count.^[32]
• Ejaculation issues – retrograde ejaculation occurs when semen enters the bladder during orgasm instead of emerging out the tip of the penis. Various health conditions can cause retrograde ejaculation including diabetes, spinal injuries, medications, and surgery of the bladder, prostate or urethra. Some men with spinal cord injuries or certain diseases can’t ejaculate semen, even though they still produce sperm.^[25]

Environmental Causes:^[31]

• Radiation or X-ray exposure can permanently reduce sperm production.
• Excessive heat from continuous hot tub, sauna, or laptop computer usage.
• Industrial chemical exposure to pesticides, herbicides, toluene, xylene, paint and varnish products, organic solvents, and benzenes.
• Heavy metal exposure to lead or other heavy metals.

Health, Lifestyle, and Other Risk Factors:^[31]

• Prolonged bicycle seat pressure
• Excessive amounts of body fat and obesity (a BMI of 30 or greater).
• Tobacco smoking and secondhand smoke exposure.^[31][33]
• Emotional stress can interfere with sperm producing hormone production.^[31]
• Recreational drug use including anabolic steroids, cocaine, and marijuana can have temporarily adverse effects on sperm production.^[31][33]
• Alcohol use and liver disease caused by excessive drinking can lower testosterone levels, cause erectile dysfunction, and decrease sperm production.^[31][33]
• Certain occupations can increase your risk of infertility, including those associated with toxins, extended use of computers or video display monitors, shift work, and work-related stress.^[31]

Proper Diagnosis of Male Infertility

The first step in addressing suspected infertility is to visit your family doctor or a general practitioner, after which you will likely be referred to a fertility specialist who will perform an extensive evaluation, which includes a lot of routine present and past medical information.^[34] Although the scheduling receptionist may or may not request that you to do so, you can gather much of the necessary data prior to your visit, such as:^[34]

Any atypical symptoms you’re experiencing, including any that may seem unrelated to infertility.
All surgeries and dates, whether unrelated or directly related, e.g., a vasectomy or vasectomy reversal.
Key personal information, including all recent major life changing events, and stressors.
Investigate your family history for fertility problems, especially male relatives (grandfather, father, and brothers).
A list of all medications, vitamins and supplements including herbs, remedies, and topicals (specialty shampoos, lotions, etc.) that you currently take.

In most cases, both partners are tested and may undergo a number of varied and gender specific tests to determine the cause of infertility. Such infertility tests can be expensive and may not be covered by insurance, so find out what your medical plan covers ahead of time. Testing usually involves a general physical examination of your genitals, followed by questions that could affect fertility about: surgeries and injuries; chronic health problems and illnesses; sexual habits; sexual development during puberty; and possibly inherited conditions.^[35]

Also standard during testing is the semen analysis wherein you’ll submit semen at the doctor’s office, which is sent to a laboratory to measure the number of sperm present, look for abnormalities in the morphology and motility, and signs of infections.^[36] Since sperm counts fluctuate from one specimen to the next, several semen analysis tests are done over a period of time to ensure accurate results.^[10] If your sperm analysis is normal, your doctor will likely recommend thorough testing of your female partner before conducting any more male infertility tests.^[37]

If deemed appropriate, your doctor may recommend additional tests to help identify the cause of your infertility which may include: testicular biopsy; anti-sperm antibody tests; specialized sperm function tests; scrotal or transrectal ultrasounds; hormone testing; post-ejaculation urinalysis; and/or genetic tests.^{[10][38][39][40][41][42]}

The Clinical Rational for Treating Male Infertility

Fertility is improved by either correcting an underlying problem, though sometimes an exact cause of infertility can’t be identified, or by trying treatments that may be helpful which may include:^{[43][44][45][46]}

• Varicocele surgery to correct an obstructed vas deferens.
• Antibiotic treatments that may cure an infection of the reproductive tract.
• Assisted reproductive technology (ART) treatments involve obtaining sperm through normal ejaculation, surgical extraction or from donor individuals, then inserted into the female genital tract, or using sperm to perform in vitro fertilization or intracytoplasmic sperm injection.
• Hormone treatments and medications