Post-Coital Test (PCT)

Pooyesh Fertility Clinic

Post-Coital Test (PCT)

 

 

The Post-Coital Test (PCT) is one of the classic diagnostic tools in the initial evaluation of infertility. It assesses the interaction between cervical mucus and sperm, specifically examining the survival and motility of sperm within the natural environment of the cervix after intercourse.

Timing of the PCT

  • The timing of this test is critical. It should be performed just before ovulation, when cervical mucus is at its peak in volume and fluidity. Accurately determining this window can be challenging, especially in women with irregular cycles.
  • Ovulation can be estimated using methods such as ovulation predictor kits or basal body temperature charting.
  • In women with regular 28-day menstrual cycles, ovulation typically occurs around day 14.
  • The test is usually performed 4–12 hours after intercourse close to the time of ovulation.
  • Couples are advised to abstain from intercourse for 2–3 days before the test.

What the PCT Evaluates?

The PCT provides information not only about the quantity and quality of cervical mucus, but also about the number and motility of sperm after they mix with cervical mucus.

Cervical mucus is graded based on several parameters, including:

  • Volume
  • Ferning pattern
  • Spinnbarkeit (stretchability)
  • Viscosity
  • Presence of inflammatory cells

A score above 10 indicates normal cervical mucus in terms of both quality and quantity.

Under the microscope, the number and motility of sperm are assessed, as well as the pH of both vaginal and cervical secretions.

Normally, vaginal pH is acidic, while cervical mucus is neutral to alkaline. At least 10 motile sperm with progressive movement should be visible in a high-power microscopic field (400x magnification).

What a Normal PCT Indicates?

  • The male partner produces an adequate number of healthy sperm.
  • Sperm are properly deposited in the vagina after intercourse.
  • Cervical glands are functioning normally.
  • Estrogen production is sufficient, indicating that ovulation is occurring.
  • No antisperm antibodies are present in cervical mucus.

Abnormal (Negative) PCT

A negative result means no sperm are present, or all sperm are immotile in the cervical mucus.

Possible Causes of Abnormal Results

Incorrect timing: The test was performed too early or too late in the cycle. This is one of the most common causes of abnormal results, and the test may need to be repeated.

Anovulation: Lack of ovulation in that cycle, sometimes due to stress or inaccurate timing of intercourse.

Low sperm count or poor motility.

Cervical abnormalities:

  • Chronic cervical infection reducing mucus production.
  • Cervical scarring or reduced mucus after procedures such as cone biopsy.
  • Cervical lesions affecting mucus quality.

Presence of antisperm antibodies in cervical secretions.

Medication effects: Drugs such as Clomiphene, Tamoxifen, Progesterone, or Danazol, often prescribed for infertility treatment, can negatively affect cervical mucus quality.

Poor mucus stretchability (low spinnbarkeit): May result from reduced serum estrogen, often indicating suboptimal follicular development.

Note: An abnormal PCT result is only clinically significant if repeat tests performed under optimal conditions consistently show abnormal findings.