Understanding Antral Follicle Count

Key Takeaways

• The antral follicle count (AFC) is a test that measures the number of small follicles in your ovaries, providing insight into a woman’s ovarian reserve and overall fertility potential.
• Your AFC results can help guide decisions about fertility treatments, lifestyle changes, and future reproductive options.
• Keep in mind your AFC is just one factor in your fertility. Age, medical history, and other elements also influence your fertility potential. Consult a fertility care expert for personalized guidance.

What Is an Antral Follicle Count?

When you're thinking about starting a family, you naturally want to understand your chances of getting pregnant. One important factor is your ovarian reserve – the quantity and quality of eggs left in your ovaries. Fertility experts can help you assess this with a simple test called an antral follicle count (AFC).

Imagine your ovaries as treasure chests filled with tiny eggs. Each egg sits inside a fluid-filled sac called a follicle. The AFC test uses an ultrasound to count the number of these follicles, giving a snapshot of your egg supply.

How Does the AFC Test Work?

During a routine transvaginal ultrasound, a small wand is inserted into the vagina to create clear images of your ovaries. The technician will typically count the follicles that are between 2 and 10 millimeters in diameter. Follicles falling within this size range are the most likely to mature and release an egg during ovulation.

According to Endotext, AFC can be evaluated at any point in the menstrual cycle, including during hormone treatment or pregnancy. While no test is perfect, the AFC test has proven more accurate and reliable for assessing ovarian function compared to traditional tests like FSH, estradiol, and the clomiphene citrate challenge test.  

How Many Antral Follicles Are Normal?

A higher AFC typically indicates a healthy reserve of eggs. A lower AFC might suggest a reduced egg count, potentially making conception more challenging (particularly with treatments like in vitro fertilization.)

Your AFC naturally declines as you age, with the most significant drop happening between 35 and 39.  While a lower AFC might seem concerning, remember that a healthy pregnancy is still possible even with a lower egg count.

Research in Fertility and Sterility shows the following average AFC numbers by age:

• Age 25-29:   21.8 antral follicles
• Age 30-34:   17.8 antral follicles
• Age 35-39:   8.4 antral follicles
• Age 40-45:   3.9 antral follicles 

It’s important to note that the averages above are based on females with regular menstrual cycles. 

AFC and Fertility Treatments

Your AFC can help guide your fertility treatment plan, especially for procedures like IVF (in vitro fertilization) and IUI (intrauterine insemination), as explained below.  

• IUI Treatments: For IUI, having multiple eggs mature at once can lead to complications. Your AFC helps doctors assess the risk of too many follicles developing, so they can adjust medication accordingly.
• IVF Treatments: In IVF, having a higher number of mature follicles can significantly enhance the chances of success. Your antral follicle count plays a crucial role in this process by helping doctors tailor the medication dosage to stimulate the ovaries effectively, ensuring optimal egg production. A 2019 study found a strong link between the number of follicles (AFC) and successful pregnancies after IVF/ICSI treatment. By also considering factors like the cause of infertility, age, and ovarian response, AFC levels can help predict the chances of pregnancy. Furthermore, this information can guide couples seeking fertility treatments and assist doctors in selecting the best ovarian stimulation protocols.

Bottom Line

Our doctors are here to offer personalized guidance and expert advice to help you explore your options for achieving pregnancy. Remember, your AFC is just one piece of the puzzle. Age, medical history, and other factors also play a role in your overall fertility potential.  Reach out today to book an appointment, and let us help you on your journey to parenthood.

This information is for basic knowledge and informational purposes only. It is not intended to be a substitute for professional medical advice. Always check with your physician or other qualified healthcare expert with any questions you may have regarding a medical condition.