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1. No Sperm (azoospermia)
Possible causes include
Testicular
Failure
– inability to produce sperm for no apparent reason or due to trauma to the
testicles, severe mumps infection after puberty, chemotherapy/ radiotherapy for
cancer.
Absent/
blocked vas deferens - the testicles produce sperm, but
the tubes which carry the sperm are blocked.
The pituitary gland does not produce sufficient hormones.
Genetic defects e.g. chromosomal abnormality such as Klinefelter's syndrome and
Y chromosome deletion.
In some infertile men, the absence of sperm in their ejaculate is due to
retro-grade ejaculation(during orgasm, sperm enter the bladder and mix with
urine, rather than get ejaculated into the vagina). This is a rare condition
and accounts for less than 1% of male infertility.
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2. Poor sperm quantity or quality e.g. low motility or a high
percentage of abnormal sperm.
This could be due to many factors such as
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hormone deficiency
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varicocele (abnormal swollen blood vessels around the testicles),
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infection, fever
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medication,
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social drugs such as marijuana and cocaine, heavy smoking and excess alcohol.
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frequent hot baths and saunas, warm work environment or tight underwear
Minor deficiencies can be treated with intra
uterine insemination while severe cases require
ICSI.
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3. Dysfunctional Sperm
Semen analysis is normal but 10% of the patients may have sperm which lack or
have a defective
fertilizing capacity , resulting in complete failure of
fertilization or poor fertilization of the eggs in
IVF.
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| 4. Inability to ejaculate into the vagina
This could be due to impotency, premature ejaculation, or the
inability to ejaculate.
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