Content Map Terms

Sperm Penetration Tests

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 centres 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 .

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 examination. 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

  1. 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

Current as of:
February 11, 2020

Author: Healthwise Staff
Medical Review:
Sarah Marshall MD - Family Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Femi Olatunbosun MB, FRCSC - Obstetrics and Gynecology