Analysis of gonadotropin pulsatility in hirsute women with normal menstrual cycles and in women with polycystic ovary syndrome

Objective: To study the relation between plasma gonadotropin pulsatility, a ndrogen levels, and estrogen levels in patients with polycystic ovary syndr ome (PCOS), in hirsute women with normal menstrual cycles, and in healthy w omen. Design: Prospective study. Setting: University medical center-based cellular and molecular endocrinolo gy laboratory. Patient(s): Eight healthy women (group 1), 9 hirsute women with normal mens trual cycles (group 2), and 19 women with PCOS (group 3). Intervention(s): Plasma concentrations of LH and FSH were measured by RIA e very 15 minutes for 12 hours. Main Outcome Measure(s): Rhythmic parameters of 12-hour LH and FSH secretio n. Result(s): Rhythmic parameters of 12-hour LH secretion were significantly h igher in patients with PCOS (group 3) than in controls (group 1) or in hirs ute women with normal menstrual cycles (group 2). The frequency of LH pulse s was statistically higher in patients with PCOS (group 3) than in controls (group 1). Statistically significant correlations were found when the freq uency of LH pulses was plotted against basal LH concentrations and rhythmic parameters of 12-hour LH secretion. Conclusion(s): Luteinizing hormone pulse amplitude was higher in patients w ith PCOS than in hirsute women with normal menstrual cycles or in healthy w omen. The LH pulse frequency was increased only in patients with PCOS compa red with healthy women and not in hirsute women with normal menstrual cycle s. (Fertil Steril(R) 1999:71:675-83. (C)1999 by American Society for Reprod uctive Medicine.)