Inhibin-B as a test of ovarian reserve for infertile women.

The objective of the study was to compare a standard clomiphene citrate challenge test with inhibin-B serum concentrations also obtained on cycle days 3 and 10 as a negative predictor of pregnancy in a group of 106 women at risk for compromised ovarian function. Mean duration of follow-up was 8.25 months in 95 patients with 30 pregnancies recorded (plus one biochemical). Inhibin-B concentrations on cycle days 3 and 10 were correlated only with each other and not with serum oestradiol, follicle stimulating hormone (FSH) and/or pregnancy rates. Pregnancy occurred in 34.5% (10/29) of all patients with inhibin-B values >/=45 pg/ml on cycle day 3 and in 31.8% (21/66) of those with values <45 pg/ml. For FSH >11 mIU/ml on either day, pregnancy rate was 13.6% versus 38.4% for FSH of </=9 mIU/ml (P = 0.03). This study reconfirmed the usefulness of a clomiphene citrate challenge test as an indication of ovarian reserve but failed to find clinical value for inhibin-B testing.