What an Antral Follicle Count Tells You on Ultrasound

What Is an Antral Follicle Count?

An antral follicle count, or AFC, is a transvaginal ultrasound scan that counts the small fluid-filled follicles visible in each ovary. It's typically done on day two, three, four, or five of the menstrual cycle, when hormone levels are at their most stable baseline and the count is least affected by that month's dominant follicle taking over.

antral follicle — a small, resting follicle visible on ultrasound early in the cycle, from which that month's egg is eventually selected

The scan itself takes only a few minutes and requires no needles or sedation. A clinician or sonographer places a transvaginal probe and counts the visible follicles in each ovary, then adds the two counts together for a total AFC. Because the count depends on the ultrasound machine's resolution and the reader's experience, the same ovaries can be counted somewhat differently at different clinics — a reason the trend over time, not one isolated number, often matters more.

What Counts as a Low, Typical, or High AFC?

There's no single number that separates a normal from an abnormal antral follicle count, and results are always read alongside your age, cycle history, and other test results rather than in isolation. Clinics generally describe a very low count as a signal that fewer follicles are available to grow in a given cycle, and a notably high count — often seen with polycystic ovary syndrome — as a sign the ovaries are producing more follicles than typical. Neither extreme is a verdict on your fertility.

a low ovarian reserve result does not, by itself, mean you cannot conceive 1Ref 1Practice Committee of ASRM (2020).Testing and interpreting measures of ovarian reserve: a committee opinion.A low ovarian reserve result does not by itself mean a woman cannot conceive; AFC and AMH are gonadotropin-independent, relatively cycle-stable, and used mainly to estimate response to ovarian stimulation rather than to predict natural conception.

Ovarian reserve testing — AFC alongside AMH and, less commonly now, day-3 FSH — is used mainly to estimate how the ovaries are likely to respond to fertility medication, not to predict whether or when someone will get pregnant naturally 1Ref 1Practice Committee of ASRM (2020).Testing and interpreting measures of ovarian reserve: a committee opinion.A low ovarian reserve result does not by itself mean a woman cannot conceive; AFC and AMH are gonadotropin-independent, relatively cycle-stable, and used mainly to estimate response to ovarian stimulation rather than to predict natural conception.. A woman with a low AFC can still conceive on her own; a woman with a high AFC isn't guaranteed an easy IVF cycle. The count describes egg quantity available that month, and quantity is only part of the fertility picture — egg quality, tubal patency, sperm parameters, and uterine factors all matter independently.

How Is the Antral Follicle Count Test Done?

An AFC is measured with a routine transvaginal ultrasound, typically scheduled for cycle day two through five, before any ovarian stimulation medication has started. A clinician or ultrasound technician inserts a thin probe and counts the small follicles visible in each ovary; the exam usually takes only a few minutes, needs no fasting or sedation, and most people return to work or normal activity the same day.

Many clinics draw blood for AMH on the same visit, since the two tests are read together as part of a broader evaluation. Within a standard fertility workup, ovarian reserve testing — AFC and AMH — sits alongside a history and exam, an assessment of whether ovulation is occurring, and a check of whether the fallopian tubes are open, with the male partner evaluated at the same time rather than afterward 2Ref 2Practice Committee of ASRM (2021).Fertility evaluation of infertile women: a committee opinion.A standard fertility evaluation includes history and exam, ovulation assessment, ovarian reserve testing, tubal patency testing, and concurrent evaluation of the male partner..

What Does AFC Predict — and What Doesn't It Predict?

Antral follicle count is most useful for predicting how many eggs an ovary is likely to yield in response to IVF stimulation medication, which helps a clinic choose a starting dose and protocol. It is not a pregnancy test, a measure of egg quality, and it can't tell you, on its own, how many years of fertility remain.

AFC and AMH are considered gonadotropin-independent and relatively stable across the menstrual cycle, which is part of why they're useful for planning — a result from one week is a reasonable guide to what's likely a few weeks later, unlike hormones that swing throughout the cycle 1Ref 1Practice Committee of ASRM (2020).Testing and interpreting measures of ovarian reserve: a committee opinion.A low ovarian reserve result does not by itself mean a woman cannot conceive; AFC and AMH are gonadotropin-independent, relatively cycle-stable, and used mainly to estimate response to ovarian stimulation rather than to predict natural conception.. But quantity and quality are different biological questions. A follicle count describes how many eggs are available to be retrieved; it says nothing about the chromosomal health of those eggs, which is more strongly tied to age than to any reserve test result.

a low count can change how your treatment is planned — it does not close the door on pregnancy

How Age Changes an Antral Follicle Count

Antral follicle count tends to decline with age, tracking the same overall pattern as natural fertility: fecundity declines gradually starting around age 32 and more rapidly after 37 3Ref 3American College of Obstetricians and Gynecologists (2025).Anticipatory Counseling Regarding Ovarian-Factor Fertility Decline (Committee Statement No. 22).Fecundity decreases gradually from about age 32 and more rapidly after 37; expedited evaluation is recommended for women over 35 after six months of trying, and more immediate evaluation over 40.. That's part of why a fertility evaluation is generally recommended earlier for women over 35, and sooner still after 40, so a low count can be caught and acted on while there's still time to weigh options.

ASRM and ACOG both support starting an evaluation after six months of trying, rather than the usual twelve, once a woman is over 35, and even sooner past 40 — precisely because lower reserve becomes more common with each passing year and there's less room to wait and see 3Ref 3American College of Obstetricians and Gynecologists (2025).Anticipatory Counseling Regarding Ovarian-Factor Fertility Decline (Committee Statement No. 22).Fecundity decreases gradually from about age 32 and more rapidly after 37; expedited evaluation is recommended for women over 35 after six months of trying, and more immediate evaluation over 40.. That's a population-level pattern, though. Plenty of people in their late 30s and early 40s have AFCs well within a typical range, and plenty of younger women have unexpectedly low ones. The count is personal, even when the trend is not.

Can Anything Change Your Antral Follicle Count?

Antral follicle count is thought to reflect a largely fixed underlying pool of eggs rather than something you can meaningfully raise, but a few lifestyle factors are linked to how the ovaries respond during treatment. Smoking is the clearest one: people who smoke tend to need higher doses of stimulation medication and have lower rates of success with assisted reproduction, along with a higher risk of pregnancy loss 4Ref 4Practice Committee of ASRM (2024).Tobacco or marijuana use and infertility: a committee opinion.Smokers need higher gonadotropin doses and have reduced ART success and higher pregnancy-loss risk, supporting smoking as a modifiable factor affecting ovarian response to stimulation..

There's no supplement or lifestyle change shown to increase an antral follicle count once it's been measured. Claims to the contrary are common in fertility marketing but aren't supported by the kind of evidence cited in this article. What lifestyle changes can realistically do is support a healthier treatment cycle overall — not add follicles that weren't there to begin with.

What Happens After the Count?

A single antral follicle count is one input into a larger conversation, not a standalone diagnosis. A fertility specialist typically combines it with an AMH level, your age, cycle history, and, if relevant, how you responded to any previous stimulation, before recommending a protocol or a next step. If the count is on the lower end, that shifts the conversation toward timeline and options rather than closing any of them off.

Because the count is reader- and machine-dependent, a single low reading is sometimes rechecked, particularly if it doesn't match the AMH result or your age would predict something different. It's also worth asking how many follicles were seen on each side, since the total can obscure whether the two ovaries look similar to each other or quite different.