Semen Analysis
Test OverviewA
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: - Volume. This is a measure of how much semen is
present in one ejaculation.
- Liquefaction time. Semen is a thick gel at the
time of ejaculation. It normally becomes liquid within 20 minutes after
ejaculation. Liquefaction time is the time it takes for the semen
to turn to liquid.
- Sperm count. This counts the number of
sperm present per
milliliter (mL) of semen in one ejaculation.
- Sperm morphology. This is a measure of the
percentage of sperm that have a normal shape.
- Sperm motility. This is a measure of the
percentage of sperm that can move forward normally. The number of sperm that
show normal forward movement in a certain amount of semen can also be measured. This is called
motile density.
- pH. This is a measure of the acidity (low
pH) or alkalinity (high pH) of the semen.
- White blood cell count. White blood cells are not
normally present in semen.
- Fructose level. This is a measure of the amount of
a sugar called fructose in the semen. The fructose provides energy for the
sperm.
Why It Is DoneA semen analysis is done to find out if: - A man has a reproductive problem that is
causing him to be infertile.
- A
vasectomy has been successful.
- The
reversal of a vasectomy has been successful.
How To PrepareYou 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. How It Is DoneYou 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
for testing. - The most common way to collect semen is by
masturbation. You direct the semen into a clean sample cup. Do not use a
lubricant.
- You can collect a semen sample during sex by withdrawing
your penis from your partner just before you ejaculate. You
then ejaculate into a clean sample cup. This method can be used after a
vasectomy to test for the presence of sperm. But other ways will likely be
recommended if you are testing for infertility.
- You can also
collect a semen sample during sex by using a condom. If you use a regular
condom, you will need to wash it well before you use it. This helps to remove any
powder or lubricant on the condom that might kill sperm. You may also be given a
special condom that does not have any substance on it that kills sperm
(spermicide). After you ejaculate, carefully remove the condom from your
penis. Tie a knot in the open end of the condom. Then place it in a container
that can be sealed in case the condom leaks or breaks.
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. A
semen analysis to test how well a vasectomy has worked is usually done 6 weeks
after the vasectomy. How It FeelsGetting a semen sample does not cause
any discomfort. But you may feel embarrassed about the method used to collect
it. RisksThere are no risks associated with collecting a
semen sample. ResultsA
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
lab. Semen analysisfootnote 1Semen
volume | Normal: | 2-5 milliliters (mL) (0.002-0.005 L in SI units) per
ejaculation |
|---|
| Abnormal: | An abnormally low or high semen volume is
present. This may sometimes cause fertility problems. | Liquefaction
time | Normal: | 20-30 minutes after collection |
|---|
| Abnormal: | An abnormally long liquefaction time is
present. This may be a sign of an infection. | Sperm
count | Normal: | 20 million spermatozoa per milliliter (mL) or
more 0 sperm per milliliter if the man has had a
vasectomy |
|---|
| Abnormal: | A very low sperm count is present. This
may mean
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. | Sperm shape
(morphology) | Normal: | More than 30% of the sperm have normal
shape. Kruger criteria: More than 14% of the sperm have a normal shape. |
|---|
| Abnormal: | 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. | Sperm movement
(motility) | Normal: | More than 50% of the sperm show normal
forward movement after 1 hour. |
|---|
| Abnormal: | 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 | Normal: | Semen pH of 7.1-8.0 |
|---|
| Abnormal: | An abnormally high or low semen pH can kill
sperm or affect how well they can move or can penetrate an egg. | White blood
cells | Normal: | No white blood cells or bacteria are
found. |
|---|
| Abnormal: | 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
orchitis,
varicocele,
Klinefelter syndrome, radiation treatment to the
testicles, and diseases that can cause shrinking
(atrophy) of the testicles (such as
mumps). 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
testosterone,
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. What Affects the TestYou may not be able to
have the test, or the results may not be helpful, if: - You take medicines such as cimetidine (Tagamet), male
or female hormones (testosterone,
estrogen), sulfasalazine, nitrofurantoin, or some
chemotherapy medicines.
- You use caffeine, alcohol, cocaine, marijuana, or tobacco.
- You use herbal medicines, such as St. John's wort or
high doses of echinacea.
- Your semen sample gets cold. The sperm
motility value will be low and not accurate if the semen sample gets
cold.
- You are exposed to radiation, some chemicals (such as certain
pesticides or spermicides), or prolonged heat.
- Your semen sample is
incomplete. This is more common if a sample is collected by
ways other than masturbation.
- You have not ejaculated for several days.
This may affect the semen volume.
What To Think About- A home test kit to check the sperm count has been approved by the U.S. Food and Drug Administration (FDA). This test can help a man find out if he has fertility problems.
- A semen sample collected at home must be
given to the laboratory or clinic within 1 hour. Keep the sample out of
direct sunlight. And do not allow it to 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.
- If sperm is consistently found in the semen of a man who has
had a vasectomy, it means that his surgery was not successful. If this happens, another form
of
birth control should be used to prevent pregnancy. A
low number of sperm may be present in a semen sample taken right after a
vasectomy. But sperm should not be present in samples taken later than that.
- A man whose mother took the medicine
diethylstilbestrol (DES) while pregnant with him
has an increased risk of being unable to father a child
(infertile).
- More tests may include measuring hormone levels,
such as:
- Other fertility testing may be recommended for fertility
problems. This
includes sperm penetration and the presence of antisperm antibodies. To learn more, see the topic
Infertility Testing.
ReferencesCitations- 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.
CreditsByHealthwise Staff
Primary Medical ReviewerSarah Marshall, MD - Family Medicine
Specialist Medical ReviewerFemi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology Current as ofMarch 16, 2017 Current as of:
March 16, 2017 Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier. Last modified on: 8 September 2017
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