EFFECTS OF AGING ON THE HUMAN OVARY - THE SECRETION OF IMMUNOREACTIVEALPHA-INHIBIN AND PROGESTERONE

Objective: To investigate the changes induced by age in the function a nd secretory pattern of the human ovary. Immunoreactive alpha-inhibin, E(2), and P secretion in vivo and in vitro have been compared in two different populations. Design: Prospective study. Women undergoing IVF -ET were divided into two groups according to age: group 1 (32.0 +/- 0 .7 years; mean +/- SEM) and group 2 (40.3 +/- 0.3 years). Setting: In vitro fertilization program at the Institute Valenciano de Infertilida d. Patients: A total of 33 infertile women with regular menses, underg oing IVF-ET. Interventions: Follicle aspiration performed by transvagi nal ultrasound. Four follicles per patient were aspirated in individua l plastic tubes. Granulosa-luteal cells isolated with Percoll columns and cultured in vitro up to 4 days in the presence of hCG. Main Outcom e Measures: In vitro fertilization parameters, serum levels of E(2), i mmunoreactive alpha-inhibin, and P, as well as the secretion of immuno reactive alpha-inhibin and P by the cultured granulosa-luteal cells. R esults: Serum immunoreactive alpha-inhibin levels the day of ovum pick -up were significantly lower in group 2 compared with group 1. Incubat ion of cells for 96 hours showed a significantly higher ability to acc umulate immunoreactive alpha-inhibin in group 1 than 2. Human chorioni c gonadotropin stimulated immunoreactive alpha-inhibin production afte r 96 hours. Cells from younger women displayed a significantly higher ability to secrete P than cells from older women. Human chorionic gona dotropin was able to significantly stimulate P production in group 1. Conclusions: These results confirm previous observations showing a red uced production of immunoreactive alpha-inhibin and steroids of ovarie s from older women and suggest that a reduced cellular function, rathe r than a decrease in the follicular population, is the main mechanism by which these changes are produced.