CAUSES OF MALE INFERTILITY
Male infertility has many causes--from hormonal imbalances, to physical
problems, to psychological and/or behavioral problems. Moreover,
fertility reflects a man’s “overall” health. Men who live a healthy
lifestyle are more likely to produce healthy sperm. The following
list highlights some lifestyle choices that negatively impact male fertility--it
is not all-inclusive:
· Smoking--significantly decreases both sperm count and sperm
· Prolonged use of marijuana and other recreational drugs.
· Chronic alcohol abuse.
· Anabolic steroid use--causes testicular shrinkage and infertility.
· Overly intense exercise--produces high levels of adrenal steroid
hormones which cause a
testosterone deficiency resulting in infertility.
· Inadequate vitamin C and Zinc in the diet.
· Tight underwear--increases scrotal temperature which results
in decreased sperm production.
· Exposure to environmental hazards and toxins such as pesticides,
lead, paint, radiation, radioactive
substances, mercury, benzene, boron, and heavy metals
· Malnutrition and anemia.
· Excessive stress!
Modifying these behaviors can improve a man’s fertility and should
be considered when a couple is trying to achieve pregnancy.
A small percentage of male infertility is caused by hormonal problems.
The hypothalamus-pituitary endocrine system regulates the chain of hormonal
events that enables testes to produce and effectively disseminate sperm.
Several things can go wrong with the hypothalamus-pituitary endocrine system:
· The brain can fail to release gonadotrophic-releasing hormone
(GnRH) properly. GnRH stimulates
the hormonal pathway that causes testosterone synthesis and
sperm production. A disruption in
GnRH release leads to a lack of testosterone and a cessation
in sperm production.
· The pituitary can fail to produce enough lutenizing hormone
(LH) and follicle stimulating hormone
(FSH) to stimulate the testes and testosterone/sperm production.
LH and FSH are intermediates
in the hormonal pathway responsible for testosterone and sperm
· The testes’ Leydig cells may not produce testosterone in response
to LH stimulation.
· A male may produce other hormones and chemical compounds which
interfere with the
The following is a list of hormonal disorders which can disrupt male
Elevated prolactin--a hormone associated with nursing mothers, is found
in 10 to 40 percent of infertile males. Mild elevation of prolactin
levels produces no symptoms, but greater elevations of the hormone reduces
sperm production, reduces libido and may cause impotence. This condition
responds well to the drug Parlodel (bromocriptine).
Low thyroid hormone levels--can cause poor semen quality, poor testicular
function and may disturb libido. May be caused by a diet high in
iodine. Reducing iodine intake or beginning thyroid hormone replacement
therapy can elevate sperm count. This condition is found in only
1 percent of infertile men.
Congenital Adrenal Hyperplasia:
Occurs when the pituitary is suppressed by increased levels of adrenal
androgens. Symptoms include low sperm count, an increased number
of immature sperm cells, and low sperm cell motility. Is treated
with cortisone replacement therapy. This condition is found in only
1 percent of infertile men.
Low pituitary gland output of LH and FSH. This condition arrests
sperm development and causes the progressive loss of germ cells from the
testes and causes the seminiferous tubules and Leydig (testosterone producing)
cells to deteriorate. May be treated with the drug Serophene.
However, if all germ cells are destroyed before treatment commences, the
male may be permanently infertile.
Complete pituitary gland failure--lowers growth hormone, thyroid-stimulating
hormone, and LH and FSH levels. Symptoms include: lethargy,
impotence, decreased libido, loss of secondary sex characteristics, and
normal or undersized testicles. Supplementing the missing pituitary
hormones may restore vigor and a hormone called hCG may stimulate testosterone
and sperm production.
A variety of physical problems can cause male infertility. These
problems either interfere with the sperm production process or disrupt
the pathway down which sperm travel from the testes to the tip of the penis.
These problems are usually characterized by a low sperm count and/or abnormal
sperm morphology. The following is a list of the most common physical
problems that cause male infertility:
A varicocele is an enlargement of the internal spermatic veins that
drain blood from the testicle to the abdomen (back to the heart) and are
present in 15% of the general male population and 40% of infertile men.
These images show what a variocoele looks like externally and internally.
A varicocele develops when the one way valves in these spermatic
veins are damaged causing an abnormal back flow of blood from the abdomen
into the scrotum creating a hostile environment for sperm development.
Varicocoeles may cause reduced sperm count and abnormal sperm morphology
which cause infertility. Variococles can usually be diagnosed by
a physical examination of the scrotum which can be aided by the Doppler
stethoscope and scrotal ultrasound. Varicocoele can be treated in
many ways (see treatment section), but the most successful treatments involve
Damaged Sperm Ducts:
Seven percent of infertile men cannot transport sperm from their testicles
to out of their penis. This pathway may be blocked by a number of
· A genetic or developmental mistake may block or cause the
absence of one or both tubes (which
transport the sperm from the testes to the penis).
· Scarring from tuberculosis or some STDs may block the epididymis
· An elective or accidental vasectomy may interrupt tube continuity.
Is a common problem affecting fertility that is caused by a supportive
tissue abnormality which allows the testes to twist inside the scrotum
which is characterized by extreme swelling. Torsion pinches the blood
vessels that feed the testes shut which causes testicular damage.
If emergency surgery is not performed to untwist the testes, torsion can
seriously impair fertility and cause permanent infertility if both testes
Infection and Disease:
Mumps, tuberculosis, brucellosis, gonorrhea, typhoid, influenza, smallpox,
and syphilis can cause testicular atrophy. A low sperm count and
low sperm motility are indicators of this condition. Also, elevated
FSH levels and other hormonal problems are indicative of testicular damage.
Some STDs like gonorrhea and chlamydia can cause infertility by blocking
the epididimis or tubes. These conditions are usually treated by
hormonal replacement therapy and surgery in the case of tubular blockage.
Is a genetic condition in which each cell in the human body has an
additional X chromosome--men with Klinefelter’s Syndrome have one Y and
two X chromosomes. Physical symptoms include peanut-sized testicles
and enlarged breasts. A chromosome analysis is used to confirm this
analysis. If this condition is treated in its early stages (with
the drug hCG), sperm production may commence and/or improve. However,
Klinefelter’s Syndrome eventually causes all active testicular structures
to atrophy. Once testicular failure has occurred, improving fertility
Is a condition in which semen is ejaculated into the bladder rather
than out through the urethra because the bladder sphincter does not close
during ejaculation. If this disorder is present, ejaculate volume
is small and urine may be cloudy after ejaculation. This condition
affects 1.5 percent of infertile men and may be controlled by medications
like decongestants which contract the bladder sphincter or surgical reconstruction
of the bladder neck can restore normal ejaculation.
Several sexual problems exist that can affect male fertility.
These problems are most often both psychological and physical in nature:
it is difficult to separate the physiological and physical components.
Erectile Disfunction (ED):
Also known as impotence, this condition is common and affects 20 million
American men. ED is the result of a single, or more commonly a combination
of multiple factors. In the past, ED was thought to be the result
of psychological problems, but new research indicates that 90 percent of
cases are organic in nature. However, most men who suffer from ED
have a secondary psychological problem that can worsen the situation like
performance anxiety, guilt, and low self-esteem. Many of the common
causes of impotence include: diabetes, high blood pressure, heart
and vascular disease, stress, hormone problems, pelvic surgery, trauma,
venous leak, and the side effects of frequently prescribed medications
(i.e. Prozac and other SSRIs, Propecia). Luckily, many treatment
options exist for ED depending on the cause--these will be discussed in
the treatment section.
Is defined as an inability to control the ejaculatory response for
at least thirty seconds following penetration. Premature ejaculation
becomes a fertility problem when ejaculation occurs before a man is able
to fully insert his penis into his partner’s vagina. Premature ejaculation
can be overcome by artificial insemination or by using a behavioral modification
technique called the “squeeze technique” which desensitizes the penis.
This rare psychological condition prevents men from ejaculating during
sexual intercourse even though they can ejaculate normally through masturbation.
This condition sometimes responds well to behavioral therapy; if this technique
does not work, artificial insemination can be employed using an ejaculate