Menstrual cycle

• Ovulation - every 28 days when egg is released
• 1. Ovary releases egg

  2. in prep for this uterus lining becomes thick and spongey

  3. egg goes through fallopian tube to uterus

  4. if sperm and egg fertilised it would implant into uterus wall

  5. if no fertilisation egg/uterus lining released ( period )
• Hormone 1 - FSH causes egg to mature and oestrogen production - produced by pituitary gland - travels in BLOOD to OVARIES - ALSO FSH triggers the ovaries to make oestrogen
• Hormone 2 - LH

  • stimulates egg release (ovulation) - pituitary gland releases LH after oestrogen stopped it from releasing more FSH
• Hormone 3 - oestrogen (produced in ovary)

  • maintain uterus lining - oestrogen also stops PITUITARY GLAND from releasing more FSH once the FSH has matured egg and the uterus has thickend
• Hormone 4 - progesterone

  • keeps uterus lining thick for fertilised egg to plant in (if not fertilised level of progesterone FALLS and period happens )
  • final hormone which stops pituitary gland from producing FSH and LH to prevent more eggs maturing or being released
• • FSH level rises - triggers ovaries to release oestrogen
  • as oestrogen increases it inhibits production of FSH because egg is matured (levels of FSH fall)
  • so oestrogen triggers release of LH now egg is mature ( LH levels rise (ovulation) )
  • next ovary produces progesterone (levels rise but if no fertilisation then levels FALL) (period)