Menstrual cycle

• FSH


  Secreted by the pituitary gland in the brain, travels in the blood to the ovaries and stimulates follicles
• Estrogen


  Produced by the maturing follicles inside the ovaries, this hormone causes the uterus to build up and inhibits the production of FSH
• FSH stimulates


  Estrogen production
• LH


  When the ovaries are producing too much estrogen, LH is detected by the brain which then stops producing FSH and instead produces LH, triggering ovulation and the release of an egg
• After ovulation


  1. The follicle becomes a corpus luteum and starts to produce progesterone

  2. Progesterone helps maintain the uterine lining
• If the egg is not fertilised


  The corpus luteum breaks down and progesterone levels drop