22nd May 2025

A 17-year-old female attends the paediatric endocrine clinic concerned she has not yet had a period.

A 17-year-old female attends the paediatric endocrine clinic concerned she has not yet had a period. Her past medical history is limited to bilateral inguinal hernia repair in early childhood. She is normal height and weight for her age. On examination, she has normal breast development, diminished pubic and axillary hair. External genitalia appear normal, though gynaecological examination reveals a blind-ended vagina. Serum prolactin is 398 mU/l (<400 mU/l). Which of the following is the most likely underlying diagnosis?

Select the SINGLE most appropriate option from the list below. Select ONE option only.