What is the AFC test?
AFC test or Antral follicle count is a test that involves using ultrasound to count the number of small, fluid-filled sacs (antral follicles) in the ovaries.
What are Antral follicles?
Every month, the ovary recruits multiple eggs to develop into mature eggs. These eggs can be observed as fluid-filled follicles on ultrasound by day 2 or day 3 of the menstrual cycle. Each follicle contains an egg with the potential for fertilization. Naturally, only one follicle matures during each cycle. With age, the number of follicles seen declines. Hence, the AFC test serves as a marker for measuring ovarian age or ovarian reserve.
Why do doctors perform the AFC test?
Doctors perform the AFC test to assess ovarian reserve, which measures the number of eggs that a woman has remaining in her ovaries. A higher number of antral follicles may indicate a higher ovarian reserve and potentially higher fertility, while a lower number of antral follicles may indicate a lower ovarian reserve and potentially lower fertility.
How is the AFC test performed?
To perform the antral follicle count, the doctor will use a transvaginal ultrasound probe to examine the ovaries. The probe is inserted into the vagina, and sound waves are used to create an image of the ovaries on a computer screen. The healthcare provider will count the number of antral follicles in each ovary and record the results.
When do doctors perform the AMH test?
Doctors should perform AFC tests early in your menstrual cycle. Fertility specialists or a radiologist would ideally perform this test on day 2 or day 3 of your period.
What is the normal AFC count? How to interpret results of the AFC test?
An antral follicle count of 5-15 is indicative of a normal AFC test. This means that the fertility specialist can obtain 5-15 eggs by giving medicines that can increase your chances of pregnancy.
High AFC counts
Patients with PCOS often exhibit AFC counts of over 15. In such cases, the fertility specialist can prescribe medications to retrieve a sufficient number of eggs. However, the dose of medications needs to be adjusted to minimize the risk of hyperstimulation.
Low AFC counts
AFC counts below 5 can indicate poor ovarian reserve and a risk of poor response to medications. This would be an indication to a fertility specialist to use specific protocols like minimal stimulation, pooling or adjuvants. Patients with poor ovarian reserve may be provided the option of a donor egg program.
Is AFC test Painful?
The AFC test is a simple and non-invasive procedure usually performed during the early follicular phase, which is the first few days of the menstrual cycle. Doctors typically conduct the test, and it is usually painless, causing no more discomfort than a regular vaginal examination.
Can doctors use the results of the AFC count in combination with other tests and evaluations to assess ovarian reserve and fertility?
AFC test versus AMH test
The AFC test and the AMH test are both markers of ovarian reserve. The AFC test is an ultrasound test that looks at the developing follicles early in the period. AMH test is a blood test which measures the levels of anti-müllerian hormone. Usually both tests agree in their results.
Discordant results in AFC and AMH tests can be due to cases where there is low AFC versus high AMH or vice versa. Such cases often occur due to improper storage of samples for AMH testing, high variability in the tests used, experience of the sonologist performing the AFC tests and rarely due to genetic polymorphisms affecting AMH or its receptor.