The effect of oral micronized progesterone on hormonal and metabolic parameters in anovulatory patients with polycystic ovary syndrome

Objective To investigate the effects of oral natural micronized P on hormonal and metabolic parameters in patients with polycystic ovary syndrome (PCOS) and to answer the clinical question whether induction of withdrawal bleeding is a necessity for the comparison of hormonal and metabolic data in subjects with PCOS. Design Prospective clinical study. Setting Academic medical center. Patient(s) Twenty-eight reproductive-aged women with PCOS. Main Outcome Measure(s) Blood sampling was collected at baseline, after 7 days of oral natural micronized P (200 mg) administration, and after withdrawal bleeding. At these three stages hormonal parameters and homeostasis assessment model (HOMA-IR) index were assessed in all patients. Result(s) Oral natural micronized P administration did not alter significantly insulin sensitivity index and androgen levels; however, LH was decreased when postbleeding values were compared to baseline. Nevertheless, after oral natural micronized P administration, P and 17α-hydroxyprogesterone (17-OHP) concentrations were increased, and HOMA-IR was decreased, whereas androgens levels were not altered, in comparison with baseline. Conclusion(s) The induction of withdrawal bleeding, with this regimen, does not appear to be a necessity for the assessment of hormonal and metabolic profile in anovulatory women with PCOS.