Pituitary origin of persistently elevated human chorionic gonadotropin in a patient with gonadal failure

Objective: To report a case of persistently elevated low levels of hCG to increase awareness of pituitary origin of persistently elevated hCG in patients with gonadal failure. Design: Case report and literature review. Setting: Large university-affiliated infertility practice. Patient(s): A 16-year-old patient with primary amenorrhea, normal secondary sex characteristics, ovarian failure, and a 46,XY karyotype. Her past medical history was significant for focal segmental glomerulosclerosis, leading to a diagnosis of Frasier syndrome. Intervention(s): At age 31 years, she desired pregnancy by oocyte donation and was found to have persistently elevated low levels of hCG (>35 mIU/mL). Main Outcome Measure(s): Pituitary hCG. Result(s): Both serum free β-hCG and hyperglycosylated hCG were undetectable. Total serum hCG diluted appropriately was not blocked by blocking agent and was detected in the urine. Subsequent treatment with exogenous E₂, in preparation of a donor oocyte cycle, suppressed her hCG levels (down to 8 mIU/mL). These results indicated a pituitary source of the serum hCG. Conclusion(s): This report reinforces the need to consider pituitary hCG as the origin of persistently elevated hCG levels in patients with gonadal failure. Although levels of hCG <14 mIU/mL have been considered normal in postmenopausal women, our case suggests that patients with gonadal failure at younger ages might have a higher pituitary output of hCG.