What Causes Male Infertility

What Causes Male InIertility?
Introduction
Over their liIetimes, approximately one in every Iive couples in the United States seeks inIertility
care. Surprisingly, only halI oI
couples who are trying to become pregnant achieve pregnancy easily and about one in ten
American couples oI reproductive
age are involuntary inIertile; male inIertility accounts Ior halI oI these cases. Despite the relative
importance oI inIertility due to
the male, inIertility evaluations have traditionally Iocused on women, because women tend to
seek gynecological care and
because men oIten are reluctant to seek advice.
A variety oI disorders ranging Irom hormonal disturbances to physical problems, to
psychological problems can cause male
inIertility. Although many treatment options are now available, in many cases treatment will not
work. In many instances, male
inIertility is caused by testicular damage resulting in an inability oI the testicle to produce
sperm. Once damaged, the testicle will
not usually regain its sperm-making capabilities; this aspect oI male inIertility is analogous to
menopause (though not natural like
menopause) Ior women and cannot usually be treated. Despite medicine`s limited ability to treat
male inIertility, many
successIul treatment options are available Ior its many causes. Besides testicular damage, the
main causes oI male inIertility are
low sperm production and poor sperm quality.

The Causes oI Male InIertility
Male inIertility has many causes--Irom hormonal imbalances, to physical problems, to
psychological and/or behavioral problems. Moreover, Iertility reIlects a man`s 'overall¨ health.
Men who live a healthy liIestyle are more likely to produce healthy sperm. The Iollowing list
highlights some liIestyle choices that negatively impact male Iertility--it is not all-inclusive:
· Smoking--signiIicantly decreases both sperm count and sperm cell motility.
· Prolonged use oI marijuana and other recreational drugs.
· Chronic alcohol abuse.
· Anabolic steroid use--causes testicular shrinkage and inIertility.
· Overly intense exercise--produces high levels oI adrenal steroid hormones which cause a
testosterone deIiciency resulting in inIertility.
· 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!
ModiIying these behaviors can improve a man`s Iertility and should be considered when a couple
is trying to achieve pregnancy.
Hormonal Problems
A small percentage oI male inIertility is caused by hormonal problems. The hypothalamus-
pituitary endocrine system regulates the chain oI hormonal events that enables testes to produce
and eIIectively disseminate sperm. Several things can go wrong with the hypothalamus-pituitary
endocrine system:
· The brain can Iail 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 oI testosterone and a cessation in sperm production.
· The pituitary can Iail to produce enough lutenizing hormone (LH) and Iollicle stimulating
hormone
(FSH) to stimulate the testes and testosterone/sperm production. LH and FSH are intermediates
in the hormonal pathway responsible Ior testosterone and sperm production.
· The testes` Leydig cells may not produce testosterone in response to LH stimulation.
· A male may produce other hormones and chemical compounds which interIere with the
sex-hormone balance.
The Iollowing is a list oI hormonal disorders which can disrupt male inIertility:
Hyperprolactinemia:
Elevated prolactin--a hormone associated with nursing mothers, is Iound in 10 to 40 percent oI
inIertile males. Mild elevation oI prolactin levels produces no symptoms, but greater elevations
oI the hormone reduces sperm production, reduces libido and may cause impotence. This
condition responds well to the drug Parlodel (bromocriptine).
Hypothyroidism:
Low thyroid hormone levels--can cause poor semen quality, poor testicular Iunction 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 Iound in only 1
percent oI inIertile men.
Congenital Adrenal Hyperplasia:
Occurs when the pituitary is suppressed by increased levels oI adrenal androgens. Symptoms
include low sperm count, an increased number oI immature sperm cells, and low sperm cell
motility. Is treated with cortisone replacement therapy. This condition is Iound in only 1 percent
oI inIertile men.
Hypogonadotropic Hypopituitarism:
Low pituitary gland output oI LH and FSH. This condition arrests sperm development and
causes the progressive loss oI germ cells Irom the testes and causes the seminiIerous tubules and
Leydig (testosterone producing) cells to deteriorate. May be treated with the drug Serophene.
However, iI all germ cells are destroyed beIore treatment commences, the male may be
permanently inIertile.
PanhypopituitaIism:
Complete pituitary gland Iailure--lowers growth hormone, thyroid-stimulating hormone, and LH
and FSH levels. Symptoms include: lethargy, impotence, decreased libido, loss oI 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.
Physical Problems
A variety oI physical problems can cause male inIertility. These problems either interIere with
the sperm production process or disrupt the pathway down which sperm travel Irom the testes to
the tip oI the penis. These problems are usually characterized by a low sperm count and/or
abnormal sperm morphology. The Iollowing is a list oI the most common physical problems that
cause male inIertility:
Variocoele:
A varicocele is an enlargement oI the internal spermatic veins that drain blood Irom the testicle
to the abdomen (back to the heart) and are present in 15° oI the general male population and
40° oI inIertile 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 Ilow oI blood Irom the abdomen into the scrotum creating a hostile
environment Ior sperm development. Varicocoeles may cause reduced sperm count and
abnormal sperm morphology which cause inIertility. Variococles can usually be diagnosed by a
physical examination oI 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
successIul treatments involve corrective surgery.
Damaged Sperm Ducts:
Seven percent oI inIertile men cannot transport sperm Irom their testicles to out oI their penis.
This pathway may be blocked by a number oI conditions:
· A genetic or developmental mistake may block or cause the absence oI one or both tubes
(which
transport the sperm Irom the testes to the penis).
· Scarring Irom tuberculosis or some STDs may block the epididymis or tubes.
· An elective or accidental vasectomy may interrupt tube continuity.
Torsion:
Is a common problem aIIecting Iertility 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 Ieed the testes shut which causes testicular damage. II emergency
surgery is not perIormed to untwist the testes, torsion can seriously impair Iertility and cause
permanent inIertility iI both testes twist.
InIection and Disease:
Mumps, tuberculosis, brucellosis, gonorrhea, typhoid, inIluenza, smallpox, and syphilis can
cause testicular atrophy. A low sperm count and low sperm motility are indicators oI this
condition. Also, elevated FSH levels and other hormonal problems are indicative oI testicular
damage. Some STDs like gonorrhea and chlamydia can cause inIertility by blocking the
epididimis or tubes. These conditions are usually treated by hormonal replacement therapy and
surgery in the case oI tubular blockage.
KlineIelter`s Syndrome:
Is a genetic condition in which each cell in the human body has an additional X chromosome--
men with KlineIelter`s Syndrome have one Y and two X chromosomes. Physical symptoms
include peanut-sized testicles and enlarged breasts. A chromosome analysis is used to conIirm
this analysis. II this condition is treated in its early stages (with the drug hCG), sperm
production may commence and/or improve. However, KlineIelter`s Syndrome eventually causes
all active testicular structures to atrophy. Once testicular Iailure has occurred, improving Iertility
is impossible.
Retrograde Ejaculation:
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. II this disorder is present,
ejaculate volume is small and urine may be cloudy aIter ejaculation. This condition aIIects 1.5
percent oI inIertile men and may be controlled by medications like decongestants which contract
the bladder sphincter or surgical reconstruction oI the bladder neck can restore normal
ejaculation.
Psychological/Physical/Behavioral Problems:
Several sexual problems exist that can aIIect male Iertility. These problems are most oIten both
psychological and physical in nature: it is diIIicult to separate the physiological and physical
components.
Erectile DisIunction (ED):
Also known as impotence, this condition is common and aIIects 20 million American men. ED
is the result oI a single, or more commonly a combination oI multiple Iactors. In the past, ED
was thought to be the result oI psychological problems, but new research indicates that 90
percent oI cases are organic in nature. However, most men who suIIer Irom ED have a
secondary psychological problem that can worsen the situation like perIormance anxiety, guilt,
and low selI-esteem. Many oI the common causes oI impotence include: diabetes, high blood
pressure, heart and vascular disease, stress, hormone problems, pelvic surgery, trauma, venous
leak, and the side eIIects oI Irequently prescribed medications (i.e. Prozac and other SSRIs,
Propecia). Luckily, many treatment options exist Ior ED depending on the cause--these will be
discussed in the treatment section.
Premature Ejaculation:
Is deIined as an inability to control the ejaculatory response Ior at least thirty seconds Iollowing
penetration. Premature ejaculation becomes a Iertility problem when ejaculation occurs beIore a
man is able to Iully insert his penis into his partner`s vagina. Premature ejaculation can be
overcome by artiIicial insemination or by using a behavioral modiIication technique called the
'squeeze technique¨ which desensitizes the penis.
Ejaculatory Incompetence:
This rare psychological condition prevents men Irom ejaculating during sexual intercourse even
though they can ejaculate normally through masturbation. This condition sometimes responds
well to behavioral therapy; iI this technique does not work, artiIicial insemination can be
employed using an ejaculate Irom masturbation.
Testing Ior Male InIertility
Testing Ior male inIertility can be complicated, time consuming and expensive. Because the end
results oI the many disparate problems that cause male inIertility are low sperm count, abnormal
sperm shape, and poor sperm motility, additional tests besides a semen analysis (described
below) are required to pinpoint the cause oI the inIertility.
The evaluation oI the male begins with a history, physical examination, and two semen analyses.
Semen Analysis:
At least two semen samples collected on separate days by masturbation are recommended. Each
sample should be collected aIter abstaining Irom ejaculation Ior at least 48 hours, but not Ior
longer than 3-5 days. The complete ejaculate should be collected and must be examined within
an hour oI collection Ior optimal accuracy. A general semen evaluation includes a determination
oI the time it takes Ior the semen to become liquid and an examination oI the semen`s volume,
consistency, and pH. The semen is also microscopically evaluated Ior sperm count, motility,
sperm shape, agglutination (the sperm`s propensity to clump together), and the presence oI
Ioreign elements such as bacteria. According to the World Health Organization, a normal
ejaculate should have more than 50 million sperm per milliliter; at least 60 percent oI the sperm
should have Iorward motility, and more than 60 percent should have a normal morphology.
Contradictions to these criteria indicate a condition that is causing the male inIertility.
To pinpoint the cause oI inIertility, a variety oI other tests may be perIormed:
· Hormone evaluation--measures blood levels oI the hormones involved in sperm production,
abnormal hormonal levels are indicative oI the hormonal problems described that cause
inIertility.
· Semen culture--checks Ior bacteria in the semen which either cause or indicate a genital
inIection
that may cause inIertility.
· Biochemical analysis oI semen--measures various chemical in semen; a chemical imbalance
may
impair Iertility.
· Post-coital/cervical mucus test--checks the compatibility oI a man`s sperm with the mucus oI
his
partner`s cervix. II the sperm and mucus are incompatible, the sperm is unable to pass through
the
mucus into the Iallopian tubes and Iertilize the egg.
· Sperm penetration assay (Hamster test)--measures sperm-egg membrane Iusion using hamster
eggs a man`s sperm: tests the capability oI the sperm to penetrate the egg during IVF.
· A thorough physical examination and history can diagnose physical problems such as
varicocoeles,
KlineIelter`s Syndrome, retrograde ejaculation, erectile disIunction, and premature ejaculation.
· An absence oI sperm in the semen sample is indicative oI ejaculatory incompetence, retrograde
ejaculation, or one oI the conditions that block the spermatic ducts.
Treating Male InIertility
A wide variety oI treatment options are available Ior the many causes oI male inIertility. Simple
liIestyle changes, like abstaining Irom alcohol, tobacco, and illicit drugs can improve male
Iertility. A healthy diet, suIIicient exercise (but not excessive exercise), and proper amounts oI
vitamin B12, vitamin C, and zinc also improve Iertility.
Treating Hormonal Problems:
Several drugs are available to treat pituitary and hormonal imbalances:
· II LH and FSH levels are low and the hypothalamus and pituitary gland are Iunctional, the drug
clomiphene citrate (Serophene, Clomid) is able to stimulate the hypothalamus to release GnRH
at
regular intervals and restore Iertility.
· II the pituitary is malIunctioning and not manuIacturing the necessary sex hormones, hormone
replacement therapy can restore Iertility. Injections oI hCG (human chorionic gonadotropin)
increases the LH supply and can stimulate the testes to produce testosterone and sperm.
· II unresponsive to hCG, the drug Pergonal (a combination oI LH and FSH) can stimulate sperm
production.
· The drug Parlodel (bromocriptine) can correct hyperprolactinemia.
· Cortisone replacement therapy can lower abnormally high androgen levels and allow the
pituitary
to Iunction normally to restore Iertility.
· Hormone replacement therapy usually works in about 4 months.
Treating Physical Problems:
Varicocele: Are most successIully repaired by microsurgery. Surgical repair improves the
semen in 70 percent oI men and results in pregnancy in 60 percent oI couples. Surgery involves
the interruption oI the damaged testicular veins. Men who are inIertile due to varicoceles can
also achieve Iertilization via intrauterine insemination, in-vitro Iertilization (IVF--more on this
technique later), and treatment with the drug clomid.
Blocked Ducts: As mentioned earlier, the path through which sperm pass Irom the testicle to
outside oI the penis can become interrupted or blocked by several conditions. In the case oI
voluntary or accidental vasectomy, a vasectomy reversal can be perIormed which reconnects the
testicle to the vas deIerens. Tubal scarring due to an STD or tuberculosis can also be Iixed by
microsurgical techniques. In the cases oI a congenital absence oI the vas deIerens, Iailed
vasectomy reversals, and other irreparable obstructions, men`s sperm can be retrieved via three
methods. Once sperm is retrieved, the sperm are used to Iertilize the egg oI a woman who has
undergone a typical IVF cycle.
Sperm retrieval methods are:
· Micro Epididymal Sperm Aspiration (MESA)--involves a delicate surgical technique that
utilizes
a microscope to get a sperm sample Irom a location proximal to the tubal obstruction.
· Percutaneous Epididymal Sperm Aspiration (PESA)--a small needle is used to aspirate sperm
Irom a location proximal to the tubal obstruction.
· Testicular Sperm Biopsy (TESE)--a small biopsy oI testicular tissue is taken and a sperm
sample is
removed Irom the biopsy.
Ejaculatory Disfunction: Men who suIIer Irom conditions that render them unable to ejaculate
(neurologic disease, traumatic injury, or surgical complication), can achieve ejaculation by two
currently used techniques.
· Vibratory stimulation employs a custom designed mechanical vibrator to stimulate the
underside oI
the glans penis to induce a reIlex ejaculation. This technique only works in patients with an
intact
ejaculatory reIlex arc.
· For men Ior which vibratory stimulation is ineIIective,
a procedure called electroejaculation can be
used to induce ejaculation. A specially designed
electric probe is inserted into the rectum next
to the prostate. A current generated by the
device stimulates the nerves oI the pelvic muscles to
induce a contraction and cause an ejaculation.
Retrograde ejaculation can be treated with decongestant medication (which causes the bladder
sphincter to close and allows semen to pass to the penis) or by tubal constructive surgery.
Treating Psychological/Physical Problems:
Erectile Dysfunction: Treatment Ior ED can be divided into Iour broad categories,
pharmacological, mechanical, surgical, and psychological.
· Pharmacological treatment: Involves the delivery oI medications that restore erections.
Several
drugs are currently used to treat ED. SildenaIil (Viagra) is taken orally to increase penile blood
Ilow; it is highly eIIective. Caverject is a drug injected directly into the penis to cause an
erection; it is highly eIIective. Papaverine is another injectible drug that is highly eIIective.
Yohimbine is a dietary supplement taken orally that is moderately eIIective. Testosterone
replacement therapy is highly eIIective Ior men with low testosterone levels.
· Mechanical Treatment: Involves the use oI a vacuum erection device with a constriction ring.
The vacuum device vacuums the penis into an erection and the constriction ring keeps blood
Irom
exiting the spongy bodies oI the penis to maintain the erection. This treatment is eIIective but
obviously cumbersome.
· Surgical Treatment: Involves the use oI implants or the correction oI vascular
damage/blockage
to restore erectile capacity. Penile implants work excellently: there are 2 types. A semi-rigid
implant keeps the penis in a perpetual semi-rigid state. InIlatable implants allow the man to
'pump¨ his penis into an erection. Arterial and venous reconstructive surgery works
moderately
well and may restore a man`s ability to achieve an erection.
· Psychological therapy is useIul in the cases oI ED which are a direct result oI psychological
causes. These patients may also beneIit Irom pharmacological or combination therapy.
Treating Premature Ejaculation:
Premature ejaculation can be treated by the squeeze technique in which a man is stimulated until
close to orgasm and then his Irenulum is squeezed by his partner. This procedure is repeated
until the penis becomes desensitized and longer intercourse becomes Ieasible. Premature
ejaculation can also be treated by collecting the ejaculate and using artiIicial insemination to
Iertilize the egg.
Treating Ejaculatory Incompetence:
Ejaculatory incompetence can be treated by behavioral therapy in some cases. With behavioral
therapy, ejaculation may be stimulated by combining masturbation and manual stimulation with
eventual penile insertion into the vagina. II this therapy does not work, artiIicial insemination
with an ejaculate obtained through masturbation can be used to overcome inIertility.