Decreased inhibin tone and increased activin A secretion characterize reproductive aging in women

• Published in: Fertility and sterility Vol. 71; no. 4; pp. 658 - 662
• Main Authors: Santoro, Nanette, Adel, Tovaghgol, Skurnick, Joan H
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY Elsevier Inc 01.04.1999; Elsevier Science
• Subjects: activin; Activins; Adult; Aging; Biological and medical sciences; Estradiol - blood; Female; Follicle Stimulating Hormone - blood; Follicular Phase - blood; FSH; Fundamental and applied biological sciences. Psychology; Hormone metabolism and regulation; Humans; inhibin; Inhibins - blood; Luteal Phase - blood; Luteinizing Hormone - blood; Mammalian female genital system; Middle Aged; Progesterone - blood; Quality Control; Vertebrates: reproduction; FSH; aging; activin; inhibin; Human; Reproduction; Adenohypophyseal hormone; Menstrual cycle; Secretion; Ageing; Inhibin; Gonadotropin; Activin; Woman; Age; Follicle stimulating hormone
• ISSN: 0015-0282; 1556-5653
• DOI: 10.1016/S0015-0282(98)00529-9

Objective: We hypothesized that the increased FSH noted in older reproductive-aged women is due to both decreased inhibin and increased activin A secretion. Design: Comparative clinical study. Setting: An academic research center. Patient(s): Five cycling women, aged 43 to 47, were compared to five midreproductive women, aged 19 to 38. Intervention(s): Specimens taken every 2 to 3 days were assayed for inhibin A and B and activin A. Main Outcome Measure(s): Integrated concentrations of inhibin A, inhibin B, and activin A in the follicular phase, luteal phase, and whole cycle. Result(s): Follicular inhibin B was reduced in older versus younger women (504 ± 82 versus 748 ± 72 total pg). Luteal inhibin A was reduced in older versus younger women (668 ± 72 versus 1152 ± 216 total pg). Activin A was elevated throughout the cycle of older versus younger women, without within-cycle fluctuations (21 ± 2 versus 11 ± 1 total ng). Conclusion(s): Lack of restraint by inhibin A and inhibin B contributes to the FSH rise associated with reproductive aging. This loss of restraint occurs in a tandem fashion, with inhibin B reduction before ovulation and inhibin A reduction after ovulation. Activin A may also play an endocrine role in maintaining elevated FSH in older reproductive-aged women.