Transvaginal sonography-based antral follicle count (AFC) appears to be a straightforward method of estimating the likely response to in vitro fertilization (IVF), Dutch researchers report.

Transvaginal sonography-based antral follicle count (AFC) appears to be a straightforward method of estimating the likely response to in vitro fertilization (IVF), Dutch researchers report in the March 15th issue of Reproductive Biology and Endocrinology.

Dr. Janet J. Kwee of the Free University Medical Center, Amsterdam and colleagues studied 110 regularly menstruating patients who were randomized to undergo the exogenous FSH ovarian reserve test (EFORT) and the clomiphene citrate challenge test (CCCT). All also underwent AFC and sonography to measure basal ovarian volume (BOV).

All subjects then had standard IVF treatment and the result of ovarian hyperstimulation on the total number of follicles during this treatment was used to gauge the success of the prediction methods.

The researchers found that the best prediction of ovarian reserve was seen in a multiple regression prediction model that included, AFC, Inhibin B-increment in the EFORT and BOV simultaneously.

Poor response was best predicted by the CCCT and the FSH followed by the AFC. However, results were similar.

For hyperresponsiveness, AFC and the inhibin B-increment in the EFORT test performed equally well. However, the AFC had better test characteristics, with a sensitivity of 82 per cent and a specificity of 89 per cent.

"The follicle count is just as good a test for ovarian response as expensive and time consuming endocrine tests," said Dr. Kwee in a statement. Moreover, the AFC appears to be "the only test able to reliably predict low and high responders."

Reprod Biol Endocrinol 2007.