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Published on: June 7, 2012
Estriol administration modulates luteinizing hormone secretion in women with functional hypothalamic amenorrhea
Alessandro D Genazzani1, Blazej Meczekalski, Agnieszka Podfigurna-Stopa
1Department of Obstetrics and Gynecology, University of Modena and Reggio Emilia, Modena, Italy. algen@unimo.it
Objective:
To evaluate the influence of estriol administration on the hypothalamus-pituitary function and gonadotropins secretion in patients affected by 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 μg 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 (E(2)), androstenedione (A), 17α-hydroxyprogesterone (17-OHP), cortisol, androstenedione (A), testosterone (T), thyroid-stimulating hormone (TSH), free triiodothyronine (fT(3)), free thyroxine (fT(4)), and insulin, and pulse detection.
Result(S):
After treatment, the FHA patients showed a statistically significant increase of LH plasma levels (from 0.7 ± 0.1 mIU/mL to 3.5 ± 0.3 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 was a statistically significant increase.
Conclusion(S):
Estriol administration induced the increase of LH plasma levels in FHA and improved GnRH-induced LH secretion. These findings suggest that estriol administration modulates the neuroendocrine control of the hypothalamus-pituitary unit and induces the recovery of LH synthesis and secretion in hypogonadotropic patients with FHA.
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