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Male Infertility
The incidence of infertility in newly married couples is approximately
10-15 percent. Ninety percent of "normal" couples who are attempting to
conceive a child will be successful within one year. Approximately 20
percent of cases of infertility are due exclusively to a "male factor",
and in 30-40 percent of cases, both male and female factors will affect
fertility. In women fertility peaks at age 24 and thereafter declines with
advancing age.
The goals of male infertility evaluation
Timing of an infertility evaluation
The timing of the decision to proceed with an infertility evaluation
varies from couple to couple. While there are no “rules” regarding the
length of time a couple should attempt conception naturally, it is
generally accepted that an infertility evaluation should be performed when
pregnancy fails to occur after one year of unprotected intercourse.
However an evaluation should be performed prior to one year if a known
male factor, such as undescended testicles or prior cancer treatment, or
female factor, including advanced reproductive age (over 35 years),
exists.
The initial male infertility evaluation
The initial evaluation for male infertility consists of a detailed
history, physical examination, and two semen analyses. The essential
elements of each are listed below.
Medical History
- Coital frequency/timing:
- Is sexual intercourse occurring during the fertile interval (days
11-15 if a 28 day cycle)?
- Duration of infertility/previous fertility:
- How long has this couple been attempting to conceive a child?
- Have there previously been any suspected or confirmed pregnancies for
either partner?
- Childhood illnesses/developmental history:
- History of birth defects such as undesdcended testicles
- Is there a history of mumps after puberty (can affect testicular
function)
- Medical illnesses:
- Urinary tract infections
- Respiratory infections
- Diabetes
- Surgical history:
- Repair of a hydrocele or hernia
- Surgery on the urethra, prostate or bladder
- Sexual history:
- Sexually transmitted diseases
- Difficulty in obtaining or maintaining an erection
- Failure to ejaculate
- Exposure to toxins:
- Heat
- Medications
- Steroids
- Recreational drugs
- Family history:
- History of infertility in siblings
- History of cystic fibrosis (almost always associated with
infertility)
Physical Examination
- General
- Muscle mass, hair distribution, breast developmentetc.
- Genitalia
- Penis/urethral opening
- Testicular size and consistency
- Vas deferens(presence/absence)
- Varicocele
- Digital rectal examination of the prostate
The Semen Analysis
- The semen analysis is the cornerstone of the male infertility
evaluations. Therefore proper collection technique is critical. Since
semen values can vary significantly from one test to the next, at least
two semen analyses, separated by one month, are recommended for the
initial evaluation. The following are recommendations for the proper
collection of semen specimens:
- Patients should abstain from ejaculation for 48-72 hours prior to
collection.
- Collection by masturbation is common, but collection through
intercourse is acceptable as long as condoms without spermicidal
substances are used.
- If the semen specimen is collected at home, it should be delivered to
the laboratory within one hour of collection and maintained at room or
body temperature during transport.
- The semen analysis provides information on several parameters
including semen volume, semen viscosity (thickness), semen pH (acidity or
alkalinity), sperm count, sperm motility (movement), and sperm morphology
(appearance). The World Health Organization has established normal values
for each. However, it should be emphasized that men with values outside
these ranges may be fertile and men with values inside these ranges may
still be infertile.
- Normal values:
- Semen Volume : 1.5-5cc
- pH: over 7.2
- Sperm Concentration: over 20mil/cc
- Sperm Motility: over 50%
- Sperm Morphology: over 30 14%
- Semen Viscosity (scale 0-4): over 3
Additional tests for male infertility
- Hormonal: Sperm production is under the control of two hormones
produced in the pituitary gland (brain), lutenizing hormone (LH) and
follicle stimulating hormone (FSH). LH stimulates the testicles to produce
the male hormone, testosterone. Sperm are produced under the influence of
FSH and high concentrations of testosterone. Therefore measurement of
levels of FSH, LH, and testosterone can be helpful in the evaluation of
male infertility, particularly in patients with sperm counts less than 10
million/cc or a history of impaired sexual function. Since the levels of
these hormones fluctuate during the day, it is recommended that these
tests be performed on blood samples drawn in the morning.
- Post-ejaculatory urinalysis: In some patients, particularly
diabetics, ejaculation occurs in a retrograde (backward) fashion. In such
cases, examination of urine following ejaculation will reveal the presence
of sperm. Sperm can be retrieved with a catheter and used for in-vitro-fertilitzation
(IVF).
- Ultrasound: Ultrasound can occasionally be helpful in the evaluation
of the infertile male. In a patient with absent semen, transrectal
ultrasound may reveal swelling of the seminal vesicles which can indicate
obstruction of the ejaculatory ducts. Scrotal ultrasound can be used to
confirm inconclusive scrotal findings on physical examination.
- Antisperm antibody testing: Antisperm antibodies are found in 3-12%
of infertile men. Antisperm antibodies are commonly found in men after a
vasectomy, but can be seen following testicular injury, torsion
(“twisting” of the testicle), or in men with genitor-urinary infections.
It is thought that antisperm antibodies may interfere with the
sperm-cervical mucus interaction or with the interaction of sperm with the
egg. Testing for antsperm antibodies should be considered when marked
reduction in sperm motility is present, when sperm agglutination (sperm
stick together) is noted, or when an abnormal post-coital test occurs.
- Post-coital test: Testing of the interaction of sperm and cervical
mucus is known as the post-coital test. An abnormal post-coital test can
indicate the presence of antisperm antibodies (see above) as well as
cervical factors contributing to infertility. Although the results of
post-coital testing are subjective, the test may be useful in directing
infertility therapy.
- Genetic testing: Genetic abnormalities are now a well recognized
cause of male infertility. A small percentage of infertile men are born
with congenital absence of both vas deferens. Many of these men will carry
a gene mutation for cystic fibrosis, a fatal respiratory disease. Seven
percent of infertile men have chromosomal abnormalities resulting in
abnormal testicular function. Ten to fifteen percent of men with marked
reduction in sperm count will have abnormalities of the “Y” chromosome.
Since many of these abnormalities will be passed on to offspring, genetic
testing and counseling should be performed prior to initiating assisted
reproduction.
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