Definition: The inability to get pregnant after
12 months of conception attempts (if the female partner is under age 35) or 6
months (if the female partner is over age 35) due to problems with the male partner.
Epidemiology: Approximately 20% of all infertility is due to male factors
alone and in an additional 30-40% of infertility there are sperm problems in
addition to female factors. Male factor infertility is more common in environmentally
compromised areas (pollution, water contaminants, pesticides, herbicides). Recent
population studies show that sperm counts have been declining universally even
though infertility has not been increasing appreciably.
Causes of Male Factor Infertility: In at least 50% of male-factor infertility,
no causes can be identified. The remainder 50% of causes can be divided into
2 major categories: environmental and genetic (acquired and congenital).
Environmental or acquired causes:
- Excess heat (occupational, e.g. truck drivers, state troopers, welders,
firefighters; habits, e.g. excess use of hot tub, tub baths, tight cloths, jockey
underwear [controversial])
- Drugs (certain antibiotics, anabolic steroids, testosterone, tobacco, marijuana,
alcohol)
- Toxins (pesticides, herbicides, heavy metals, lead, mercury, paint, paint
thinner)
- Stress (including erectile dysfunction)
- Excess exercise, including bicycling
- Chronic disease (e.g. anemia, malnutrition, cancer, neurological disease,
diabetes, obesity)
- Dietary deficiencies (e.g. zinc, vitamin C, folic acid)
- Varicocele (enlarged veins in the scrotum)
- Diseases of the male genital tract (infection, cancer, trauma, retrograde
ejaculation)
- Surgery on the male genital tract (e.g. undescended testicle, hernia)
- Obesity
Genetic and other congenital causes:
- Y-chromosome abnormalities
- Other chromosome abnormalities (e.g. Klinefelter’s XXY)
- Hormonal abnormalities (diabetes, high prolactin, thyroid abnormalities,
adrenal abnormalities, pituitary and hypothalamic abnormalities)
Diagnosis: History and physical examination are essential. The
semen analysis is the single most important diagnostic test for male infertility. Hormonal evaluation
(FSH, LH, thyroid, testosterone, prolactin) should be offered in case problems
with sperm count, motility, or morphology cannot be readily explained. At present,
most advanced infertility practices offer a semen analysis with strict sperm
shape criteria (Kruger’s, Tygerberg) that are more predictive of sperm
dysfunction than the conventional WHO criteria offered by non-specialty laboratories.
Treatment:
- Avoidance of damaging environmental
factors (smoking, heat exposure, heavy exercise, toxins, certain drugs)
- Stress
reduction
- Medications: antibiotics (if infection suspected);
fertility medications (including clomiphene or Human Chorionic Gonadotropin (HCG)
or LH/FSH by injections)
- Vitamins (questionable): Folic acid,
zinc, L-carnitine)
- Alternative Medicine (e.g. herbs, acupuncture-
questionable but generally not harmful)
- Surgery (e.g. varicocele
repair, vasectomy reversal)
- In vitro fertilization (typically
with Intracytoplasmic Sperm Injection, ICSI; if indicated, with sperm extraction
from the epididymis or testicle
©Copyright Eli Reshef MD
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