9th February 2024

A 36-year-old female with known Hashimoto’s thyroiditis has presented with an 18-month history of amenorrhoea.

A 36-year-old female with known Hashimoto’s thyroiditis has presented with an 18-month history of amenorrhoea. She has experienced hot flushes along with this. She has not changed her lifestyle and denies any significant stress. An MRI of the brain was unremarkable, and blood showed low levels of oestrogen and progesterone with elevated FSH and LH. Her cortisol and prolactin levels were normal, along with normal ACTH levels and negative 21-hydroxylase autoantibodies. 

Which of the following organs is likely affected pathologically to explain her symptoms?