Objective: To report two rare cases of gonadotropin-resistant ovary syndrome associated with secondary amenorrhea and normal levels of inhibin B. Design: Case report. Setting: Two university teaching hospitals. Patient(s): Two women presenting with secondary amenorrhea and infertility. The control group for the inhibin B levels consisted of 30 cycling women of reproductive age. Intervention(s): Medical history, physical examination, laboratory data, histologic findings, and IVF results. Main Outcome Measure(s): Diagnosis and treatment of resistant ovary syndrome. Result(s): Case 1 was a 25-year-old woman with secondary amenorrhea and primary infertility. She had high serum levels of FSH and LH, low E-2 levels, and normal inhibin B levels (62 pg/mL). Karyotype was 46,XX, and ovarian biopsy showed primordial follicles with oocytes. Administration of GnRH analogue with hMG for 15 days did not affect E-2 levels. She had a successful pregnancy with IVF using donor oocytes. Case 2 was a 24-year-old woman with secondary amenorrhea. She had elevated serum levels of FSH and LH, low E-2 levels, and normal inhibin B levels (57 pg/mL). Karyotype was 46,XX and ovarian biopsy showed primordial follicles. Administration of GnRH analogue with hMG for 12 days did not affect E-2 levels. Both women were given estrogen-progestin replacement therapy. Conclusion(s): Inhibin B has a diagnostic role in women with gonadotropin-resistant ovary syndrome associated with secondary amenorrhea. A review of the literature confirms the uniqueness of the diagnostic role of inhibin B in these cases.
