Test Overview
Sperm penetration tests check to see if a man's sperm can move
through cervical mucus and the
fallopian tubes to join with (fertilize) an egg. This
test is usually done when a couple is having trouble getting pregnant (infertility).
There are different sperm
penetration tests.
- Sperm mucus penetration. This test
checks to see if a man's sperm can move through the cervical mucus. This test is
not done very often because there are other fertility tests that give more
information about the fertility problem.
- Sperm penetration assay. This test checks to see if a man's sperm can join with an egg. (This is also called the hamster zona-free ovum test or
hamster test.) Sperm are
mixed with hamster eggs in a laboratory. The number of sperm that penetrate the
egg is measured. This test is done most often at
special fertility centers that do
in vitro fertilization.
Why It Is Done
Sperm penetration tests may be
done:
- When other tests have not found a cause for
infertility.
- To see how the sperm function when a semen analysis
test has shown some problems. Problems could include the sperm moving slowly or looking
abnormal.
- To test
sperm before doing in vitro fertilization.
How To Prepare
Talk to your doctor about any concerns
you have about the need for the test, its risks, how it will be done, or
what the results will mean. To help you understand the importance of this test,
fill out the
medical test information form(What is a PDF document?).
Sperm mucus penetration test
For women, this test
must be done during
ovulation. Follow your doctor's instructions for
checking the level of
luteinizing hormone (LH) in your urine. When you check
your LH level, do the urine test in the mid- to late morning. Do not drink
any fluids that morning until you have done the test. If your test shows that
you are ovulating, call for a doctor's visit for the next day.
For
men, the semen sample is collected after the cervical mucus sample is taken.
You should not release your sperm (ejaculate) for 2 days before the test. It is
important to not go longer than 5 days before the test without
ejaculating.
Sperm penetration assay (SPA)
The SPA only requires a semen sample to be taken.
For
men, it is important that you do not release your sperm (ejaculate) for 2 days
before the test. But do not go longer than 5 days before the test without
ejaculating.
How It Is Done
Sperm mucus penetration test
For the sperm mucus
penetration test, samples of the woman's cervical mucus and the man's semen will
be collected. In the lab, the semen is added to the mucus in a tube. After 90
minutes, the distance the sperm have moved is measured.
For the woman: a sample
of cervical mucus is collected from the woman during a pelvic exam. To learn more, see the topic
Pelvic Examination.
For the man: a semen sample is
collected by masturbation. First, you should urinate and then wash and rinse
your hands and penis before you collect the semen in a sterile cup. Do not
use lubricants or condoms when you collect the sample. If you collect the semen
sample at home, be sure to get it to the lab or clinic within 1 hour. Keep the
sample at body temperature and out of direct sunlight. Do not collect the sample by having sex and then withdrawing when you ejaculate, because vaginal
fluid may be mixed with the sperm.
Sperm penetration assay (SPA)
For the SPA, a semen sample is collected. The sperm are mixed with hamster eggs in a
laboratory. The number of sperm that can penetrate an egg is measured.
For the man: a semen sample is collected by masturbation. First, you should urinate
and then wash and rinse your hands and penis before you collect the semen in a
sterile cup. Do not use lubricants or condoms when you collect the sample.
If you collect the semen sample at home, be sure to get it to the lab or clinic
within 1 hour. Keep the sample at body temperature and out of direct sunlight.
Do not collect the sample by having sex and then withdrawing when you ejaculate, because vaginal
fluid may be mixed with the sperm.
How It Feels
Cervical mucus sample
For the woman: you may feel some pressure
or slight pain when the speculum is put into your vagina. The plastic or metal speculum
spreads apart the vaginal walls. This allows your doctor to look at the inside of
the vagina and the cervix. The speculum may be
warmed with water or lubricated with a vaginal lubricant (such as K-Y Jelly).
Try to relax your legs and hips as much as you can.
Semen sample
For the man: collecting a semen sample does not
cause any discomfort. But you may feel embarrassed about the method used to
collect it. If masturbation is against your religious beliefs, talk with your
doctor.
Risks
There is very little chance of a problem from collecting a sample of vaginal fluid or from collecting a
semen sample.
Results
Sperm penetration tests check to see
if a man's sperm can move through cervical mucus and the
fallopian tubes to join with (fertilize) an
egg.
Sperm mucus penetration test
A controlled test can
see if the cervical mucus is preventing sperm penetration. This test uses donor
sperm and the male partner's sperm. Both sperm samples are added to a sample of
the woman's cervical mucus. Donor cervical mucus may also be used with the
woman's cervical mucus.
There may be a problem with the partner's sperm if:
- The donor's sperm penetrates the mucus, but
the partner's sperm does not.
- The partner's sperm does not
penetrate the woman's or the donor's cervical mucus.
There may be a problem with the woman's mucus if
neither the partner's nor the donor's sperm penetrate the cervical
mucus.
Sperm mucus penetration testfootnote 1| Normal: | Sperm penetrate the cervical mucus and move
through it easily. |
|---|
| Abnormal: | Sperm can't penetrate the cervical mucus, or
they clump together in the mucus. Clumping may mean that the woman or man has
formed
antibodies against the sperm. If the sperm antibodies
are from the man's body, clumping may also be seen in his semen
analysis. |
|---|
Sperm penetration assay (SPA)
Results are based on
the number of sperm that can penetrate an egg. This can vary from lab to lab.
Talk with your doctor to find out if your results are normal.
Sperm penetration assay (SPA)| Normal: | Sperm penetrate the hamster
egg. |
|---|
| Abnormal: | Sperm can't penetrate the hamster
egg. |
|---|
What Affects the Test
You may not be able to
have the test, or the results may not be helpful, if:
- The semen sample has not been collected the right way.
- The test is done at a time when a woman is not
ovulating.
What To Think About
- The sperm penetration assay test may be done
before
in vitro fertilization.
- A normal sperm
penetration assay and a normal semen analysis mean that the sperm is of good
quality for in vitro fertilization. To learn more about infertility
testing, see the topic
Infertility Testing.
References
Citations
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Other Works Consulted
- Fritz MA, Speroff L (2011). Male infertility. In Clinical Gynecologic Endocrinology and Infertility, 8th ed., pp. 1249-1292. Philadelphia: Lippincott Williams and Wilkins.
- Lobo RA (2012). Infertility: Etiology, diagnostic evaluation, management, prognosis. In GM Lentz et al., eds., Comprehensive Gynecology, 6th ed., pp. 869-895. Philadelphia: Mosby.
Credits
ByHealthwise Staff
Primary Medical ReviewerSarah Marshall, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
Specialist Medical ReviewerFemi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology
Current as ofMarch 16, 2017