Antral Follicle Count (AFC) is a significant metric for assessing a woman’s reproductive health. It provides insights into ovarian reserve, which is the quantity of eggs remaining in the ovaries. Understanding AFC offers valuable information for individuals navigating their fertility journey.
What Antral Follicle Count Measures
Antral follicles are small, fluid-filled sacs within the ovaries, each containing an immature egg. These follicles measure between 2 and 10 millimeters in diameter and are visible through specialized imaging. AFC measures the number of these follicles present in both ovaries during the early phase of a menstrual cycle, typically between days 3 and 5.
This count is performed using a transvaginal ultrasound. The number of antral follicles observed reflects the pool of eggs available for that specific menstrual cycle, rather than the total lifelong egg supply. As women age, the number of these follicles naturally declines, indicating a reduction in ovarian reserve.
Why Antral Follicle Count is Important
Antral Follicle Count serves as a reliable indicator of a woman’s ovarian reserve, representing the potential for her ovaries to produce eggs. This assessment helps predict how ovaries might respond to fertility medications, particularly during treatments like in vitro fertilization (IVF). A higher AFC generally suggests a better response to ovarian stimulation.
AFC provides insights into a woman’s reproductive potential, helping fertility specialists gauge the likelihood of successful pregnancy. It offers a snapshot of the current egg supply, influencing treatment decisions and expectations. While AFC is a strong predictor, it is one of several factors considered in a comprehensive fertility evaluation.
Interpreting Antral Follicle Count Results
Interpreting Antral Follicle Count results involves considering the number of follicles observed in relation to a woman’s age. An AFC between 10 and 15 is often considered optimal for evaluating pregnancy possibilities, while a count above 10 is classified as high. A count between 9 and 21 is generally considered intermediate to normal, suggesting a good response to ovarian stimulation. A high count, over 22, indicates an excellent response to stimulation.
A low AFC, often defined as fewer than 5 or 6 follicles, suggests diminished ovarian reserve. A count of 3 to 6 follicles indicates low ovarian reserve, but this does not definitively mean an inability to conceive naturally. In some cases, a very high AFC, exceeding 35, might indicate conditions like polycystic ovary syndrome (PCOS). A low count does not always equate to infertility, as factors like egg quality and overall health are also significant.
Median AFC values vary by age:
Under 35: around 20
35-37: 17
38-40: 13
25-34: 10-13
35-40: 8-10
41-46: 5-7
A fertility specialist evaluates these numbers alongside individual circumstances to provide guidance.
Antral Follicle Count and Your Fertility Journey
Antral Follicle Count results are instrumental in guiding decisions about fertility treatments, such as IVF or intrauterine insemination (IUI). A higher AFC suggests that ovaries are likely to respond well to stimulation medications, increasing the chances of retrieving multiple eggs for procedures like IVF. Conversely, a low AFC might lead to adjustments in treatment protocols, such as higher medication dosages, or discussions about alternative options.
This assessment helps manage expectations regarding treatment outcomes and informs personalized fertility plans. While AFC is a valuable predictive tool for ovarian response, it is not a definitive diagnosis of fertility. It is considered alongside other markers of ovarian reserve, such as Anti-Müllerian Hormone (AMH) levels, and a woman’s overall medical history to form a comprehensive picture of her reproductive health.