HPO axis

• 1. hypothalamus secretes GnRH
  2. GnRH travels to anterior pituitary gland
  3. promotes release of LH and FSH
  4. LH and FSH travel to ovaries
  5. Stimulate production of oestrogen and inhibin
  6. Oestrogen helps to regular menstrual cycle and inhibin causes inhibition of activin which is responsible for stimulating GnRH production
  7. Increasing oestrogen and inhibin have negative feedback effect - decreased GnRH, LH and FSH
  8. Decreased production of oestrogen and inhibin