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semen analysis measures how much semen a man
produces. It also shows the number and quality of
sperm in the semen sample.
This test is usually one of the first tests done to help find out if a man
has a problem fathering a child (infertility). A
problem with the semen or sperm affects more than one-third of couples who
are unable to have children (infertile).
Tests that may be done
during a semen analysis include:
A semen analysis is done to find out if:
You may be asked to avoid any sexual
activity that results in ejaculation for 2 to 5 days before this test.
This helps to make sure that your sperm count will be at its highest. It also makes the test more reliable. If possible, do not avoid sexual activity for more
than 1 to 2 weeks before this test. A long time without sexual activity
can result in less active sperm.
You may be asked to avoid
drinking alcohol for a few days before the test.
Be sure to tell
your doctor about any medicines or herbal supplements you take.
You will need to produce a semen sample. This is
usually done by ejaculating into a clean sample cup. You can do this in a private
room or in a bathroom at your doctor's office or clinic. If you
live close to your doctor's office or clinic, you may be able to
collect the semen sample at home. Then you can take it to the office or clinic
If any of these methods are against your beliefs, talk with your doctor about different ways to get a sample.
If you collect the semen sample at home, the sample must be
given to the lab or clinic within 1 hour. Keep the sample out of
direct sunlight. And do not let it get cold or hot. If it is a cold day,
carry the semen sample container against your body. This helps to keep it as close to body
temperature as possible. Do not refrigerate the semen sample.
Since semen samples may vary from day to day, two or three different samples
may be checked within a 3-month period. This helps to get accurate testing.
semen analysis to test how well a vasectomy has worked is usually done 6 weeks
after the vasectomy.
Getting a semen sample does not cause
any discomfort. But you may feel embarrassed about the method used to collect
There are no risks associated with collecting a
semen analysis measures the amount of semen a man
produces. It also shows the number and quality of
sperm in the semen sample. Results of a semen analysis
are usually available within a day. Normal values may vary from lab to
2–5 milliliters (mL) (0.002–0.005 L in SI units) per
An abnormally low or high semen volume is
present. This may sometimes cause fertility problems.
20–30 minutes after collection
An abnormally long liquefaction time is
present. This may be a sign of an infection.
20 million spermatozoa per milliliter (mL) or
0 sperm per milliliter if the man has had a
A very low sperm count is present. This
infertility. But a low sperm count does not always
mean that a man can't father a child. Men with sperm counts below 1 million
have fathered children.
More than 30% of the sperm have normal
Kruger criteria: More than 14% of the sperm have a normal shape.
Sperm can be abnormal in several ways. They may have two heads or two tails, a short tail, a tiny head (pinhead), or a
round (rather than oval) head. Abnormal sperm may not be able to move normally or
to penetrate an egg. Some sperm that aren't normal are usually found in every normal
semen sample. But a high percentage of abnormal sperm may make it harder for a man to father a child.
More than 50% of the sperm show normal
forward movement after 1 hour.
Sperm must be able to move forward (or
"swim") through cervical mucus to reach an egg. A high percentage of sperm that
can't swim well may make it harder for a man to father a child.
Semen pH of 7.1–8.0
An abnormally high or low semen pH can kill
sperm or affect how well they can move or can penetrate an egg.
No white blood cells or bacteria are
Bacteria or a large number of white blood
cells are present. This may be a sign of an infection.
Certain conditions may be linked with a low or absent
sperm count. These conditions include
Klinefelter syndrome, radiation treatment to the
testicles, and diseases that can cause shrinking
(atrophy) of the testicles (such as
If a low sperm count or a high
percentage of abnormal sperm is found, more testing may be done. Other
tests may include measuring hormones, such as
luteinizing hormone (LH),
follicle-stimulating hormone (FSH), or
prolactin. A small sample (biopsy) of the
testicles may need to be checked if the sperm count or motility
is extremely low.
You may not be able to
have the test, or the results may not be helpful, if:
Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Other Works Consulted
Chernecky CC, Berger BJ (2013). Laboratory Tests and Diagnostic Procedures, 6th ed. St. Louis: Saunders.
Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
Fritz MA, Speroff L (2011). Male infertility. In
Clinical Gynecologic Endocrinology and Infertility, 8th
ed., pp. 1249–1292. Philadelphia: Lippincott Williams and Wilkins.
Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby.
ByHealthwise StaffPrimary Medical ReviewerSarah Marshall, MD - Family MedicineSpecialist Medical ReviewerFemi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology
Current as ofNovember 2, 2014
Current as of:
November 2, 2014
Sarah Marshall, MD - Family Medicine & Femi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology
How this information was developed to help you make better health decisions.
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