Post-Coital TestWhen you are diagnosed with infertility, your doctors use a variety of tests to determine the details of the causes, depending on your individual case and the unknowns about your fertility health. One test that is least understood is the postcoital test, which examines cervical mucus.

There is a common misconception that the postcoital test is performed to determine if you were successful getting pregnant. However, not enough time has passed for the sperm to fertilize the egg. Instead, looking at the cervical mucus after sex can only tell doctors if there is an incompatible interaction between the sperm and the mucus.

The postcoital test occurs just after sex, preferably in the 24 hours following intercourse. To see the most accurate results in the test, the woman must be ovulating during the optimal fertility window. Also, the couple must have abstained from sex for two to five days prior to the test and not have used any lubricants. The test collects a sample of cervical mucus and analyzes how the sperm has interacted with it.

The cervical mucus sample will have sperm remnants in it so the doctors can see the sperm quality as it interacts. Ideally, the doctors are looking for normal and motile sperm. This examination will conclude that the couple has no problems with their body chemistry, and the problem may be with ovulation or another condition that causes infertility.

However, if there are a large number of inactive or dead sperm, then there could be an antigen-antibody reaction, meaning the sperm and the mucus are incompatible. This reaction shows that the female’s immune system believes the sperm is an invading pathogen. The immune system labels the sperm as destructive and works at ridding the body of it, the same way it reacts to bacteria or viruses.

When these female antibodies are present, it indicates that alternative conception methods are required. Options available to couples who are trying to conceive with antibodies in the cervical mucus include intrauterine insemination (IUI) or in vitro fertilization (IVF).

The post-coital test can be a little awkward since you have to time sex in conjunction with your doctor’s appointment where cervical mucus is analyzed. However, the test is one of the first diagnostic steps during your infertility journey so doctors can find a treatment solution.


Marshall, MD, Sarah. “What Is a Postcoital Test?” WebMD. 19 Mar 2010: 1-2. Web. 5 Sep. 2015. .

Morris, Tracy. “Post-Coital Test (PCT).” Fertility Community. Web. 5 Sep. 2015. .