Diminished α-inhibin messenger ribonucleic acid in in vitro fertilization-embryo transfer poor responders reflects declining follicle reserve

Objectives: To quantitate and compare granulosa cell α-inhibin messenger RNA (mRNA) levels in IVF-ET poor and good responders and thereby learn how α-inhibin mRNA levels change in states of diminished ovarian responsiveness. Design: Ribonucleic acid analysis of stored luteinized granulosa cell samples. Setting: Academic tertiary care institution. Patients: Fifty-three women undergoing follicle aspiration for IVF-ET were studied. Patients were classified as poor responders (n = 16) or good responders (n = 37) according to their E₂ concentration on the day of hCG; the E₂ of poor responders was < 1,OO0 pg/mL (3,671 pmol/L) and that of good responders was ≥1,000 pg/mL (3,671 pmol/L). Main Outcome Measures: Messenger RNA levels were measured using dot blot RNA analysis. The following parameters were determined or derived: total mRNA levels, total α-inhibin mRNA levels, α-inhibin mRNA per follicle, and proportional α-inhibin mRNA as the ratio of α-inhibin mRNA:total mRNA. Results: Proportional α-inhibin mRNA and α-inhibin mRNA per follicle were not significantly different between poor responders and good responders. Total mRNA and total α-inhibin mRNA levels, however, were diminished significantly in poor responders. Conclusions: The observations that proportional α-inhibin mRNA and α-inhibin mRNA per follicle do not significantly change in poor responders, whereas total α-inhibin mRNA does, indicate that the decrease in total α-inhibin mRNA in poor responders reflects a decreased pool of total mRNA, likely because of a reduction in follicle number. These findings are in contrast to other recent reports that describe a change in granulosa cell function accompanying states of decreased ovarian responsiveness.