Antral follicle count

Antral follicle count (AFC) or basal antral follicle count is a test done for checking a womens ovarian reserve. 

A female is born with a liftieme supply of eggs and as she grows these eggs are developed. Post her puberty these follicles develop and are relased on a monthly basis. When the woman reaches menopause this supply is exhausted. 

An antral follicle is a resting follicle and appears as a small fluid fillied sac which contains the immature egg. These follicles can be measured and counted on cycle days 2, 3 and 5. The antral follicles varies every month.

Antral follicle count is rightly done on day 3 of the cycle by a Trans vaginal ultrasound.Initially the ovarian volume of both the ovaries is calculated. Further the number of small antral follicles in both the ovaries is measured. These follicles could vary in size from 2-10 mm.

Normal AFC is a bit variable in different centres. It is roughly considered to be about 3-8 per ovary. AFC count is a major predictor of the ovarian reserve and could  reflect the size of the remaining primordial follicle pool.

Low fertility is characterized by low numbers of oocytes and are usually associated with high follicle stimulating hormone levels (FSH).

It is considered to be more accurate than the basal FSH testing for older women >44 years of age when predicting IVF outcome.

When an average to high number of antral follicles (eight or more) are visible on the ultrasound, fertility specialists expect to be able to retrieve a good number of eggs and the pregnancy rates are higher than average. If few antral follicles appear, a poorer response is expected and the IVF cycle could be cancelled to try for better results the following month.


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Article Information

rID: 26587
System: Gynaecology
Tag: refs
Synonyms or Alternate Spellings:
  • Basal antral follicle count
  • AF count

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