Ovarian age-related responsiveness to human chorionic gonadotropin in women with polycystic ovary syndrome

Abstract

Ovarian steroid secretion capacity starts to decline as early as around the age of 30 yr. Whether an age-related decrease in androgen secretion, as in normal women, also occurs in women with polycystic ovary syndrome (PCOS) and whether the enhanced androgen production in PCOS remains throughout the fertile period of life are not known. The aim of this study was to determine the age-related serum basal and gonadotropin-stimulated androgen levels in women with PCOS and to compare the results with those obtained from our previous study in healthy women with normal ovaries. Human chorionic gonadotropin (hCG) stimulation tests were carried out among 42 women with PCOS (age, 16-44 yr; body mass index, 31.02 ± 1.1 kg/m2). An im injection of 5000 IU hCG was given 2-4 d after spontaneous or progestin-induced menstrual bleeding, and blood samples for LH, FSH, inhibin B, 17-hydroxyprogesterone, androstenedione (A), testosterone (T), and estradiol assays were collected at 0, 24, 48, and 96 h. In women with PCOS, basal serum T and A levels were about 50% higher than in healthy women. The responses of A and T to hCG [area under the curve (AUC), 96 h)] were significantly higher in women with PCOS than in normal women [A, 1183.6 ± 60 (±SE) vs. 814.4 ± 39 (P ≤ 0.001); T, 192.9 ± 12 vs. 117.4 ± 6; P ≤ 0.001]. In PCOS women, the hCG-stimulated A levels correlated negatively with age (AUC of A: r = -0.044; P = 0.004), and a similar trend was also observed in AUC T levels (AUC of T: r = -0.125, P = 0.425). Despite the higher androgen secretion capacity in PCOS, the basal and hCG-stimulated serum estradiol levels were similar to those observed in normal women. LH correlated positively with age, but basal FSH and inhibin B levels remained unchanged. In conclusion, in PCOS basal serum levels of androgens and ovarian androgen secretion capacity are markedly increased and remain high throughout the reproductive years, although the decreasing ovarian capacity to release androgens in response to hCG stimulation seen in healthy women also occurs in PCOS.