Estriol administration modulates luteinizing hormone secretion in women with functional hypothalamic amenorrhea

Objective: To evaluate the influence of estriol administration on the hypothalamus-pituitary function and gonadotropins secretion in patients affectedby functional hypothalamic amenorrhea (FHA).Design: Controlled clinical study.Setting: Patients with FHA in a clinical research environment.Patient(s): Twelve hypogonadotropic patients affected by FHA.Intervention(s): Pulsatility study of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and a gonadotropin-releasing hormone (GnRH)test (10 mg in bolus) at baseline condition and after 8 weeks of therapy with 2 mg/day of estriol.Main Outcome Measure(s): Measurements of plasma LH, FSH, estradiol (E2), androstenedione (A), 17a-hydroxyprogesterone (17-OHP), cortisol,androstenedione (A), testosterone (T), thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), and insulin, and pulsedetection.Result(s): After treatment, the FHA patients showed a statistically significant increase of LH plasma levels (from 0.7 0.1 mIU/mL to 3.50.3 mIU/mL)and a statistically significant increase of LH pulse amplitude with no changes in LH pulse frequency. In addition, the LH response to the GnRH bolus wasa statistically significant increase.Conclusion(s): Estriol administration induced the increase of LH plasma levels in FHA and improved GnRH-induced LH secretion. These findingssuggest that estriol administration modulates the neuroendocrine control of the hypothalamus-pituitary unit and induces the recovery of LHsynthesis and secretion in hypogonadotropic patients with FHA.