Objective: To test the hypothesis that women with declining ovarian reserve may demonstrate a decrease in day 3 serum inhibin B levels before a rise in day 3 serum FSH levels.
Design: Case-control study.
Setting: Tertiary care fertility center.
Patient(s): One hundred nine women with nonovarian infertility (tubal factor or male factor) and 47 women with declining ovarian reserve who underwent assisted reproductive techniques.
Intervention(s): None.
Main outcome measure(s): Serum inhibin B and FSH levels, number of ampules of gonadotropins administered, E2 levels on the day of hCG administration, number of oocytes retrieved, clinical pregnancy rate, and cycle cancellation rate.
Result(s): Women who had declining ovarian reserve as demonstrated by an increased gonadotropin requirement, a decreased E2 response, fewer retrieved oocytes, a lower clinical pregnancy rate, and a higher cycle cancellation rate had lower day 3 serum inhibin B levels despite having nonelevated day 3 FSH levels similar to those of women with nonovarian infertility.
Conclusion(s): Women with declining ovarian responsiveness and clinical outcomes consistent with declining ovarian reserve had decreased day 3 serum inhibin B levels despite having nonelevated day 3 serum FSH concentrations. Declining ovarian reserve may be demonstrated by a decrease in day 3 inhibin B levels before a rise in day 3 FSH levels.