Hormones

• Oestrogen can be used to prevent the release of an egg, if it is taken every day it inhibits the production of FSH so egg development stops.
• Progesterone stimulates the production of a thick mucus which prevents any sperm reaching the egg
• The pill contains oestrogen and progesterone. It is over 99% effective at preventing pregnancy but it can cause side effects. It doesnt protect against sexually transmitted diseases
• The patch

  • Contains oestrogen and progesterone
  • Lasts around a week
• Implant

  • Releases a continous ammount of progesterone, which stops the ovaries releasing eggs, prevents fertillised eggs from implanting in the uterus and makes it hard for sperm to swim to the egg
  • Can last for three years
• IUD

  • Kills sperm and prevents implantation of a fertillised egg
  • Plastic IUDs release progesterone
  • Copper IUDs prevent sperm surviving in the uterus