controlling fertility

• oestrogen can be used to prevent the release of an egg, so can be used as contraception
• progesterone can also be used to prevent fertility, as it causes thick mucus to form in the uterus, preventing any sperm from getting through to the egg
• the 'pill' is an oral contraception containing oestrogen and progesterone
• the contraceptive path contains oestrogen and progesterone. it is stuck to the skin, each lasting a week.
• the contraceptive implant is inserted under the skin and releases progesterone for 3 years. it works by releasing a continuous amount of progesterone
• the contraceptive injection contains progesterone, each dose lasting 2 to 3 months
• an intrauterine device is a T-shaped device that is inserted into the uterus to kill sperm and prevent implantation of a fertilised egg.
• there are two main types of intrauterine devices, platic IUDs that release progesterone and copper IUDS that prevent sperm from surviving in the uterus.
• non-hormonal forms of contraception include condoms, a diaphragm and spermicide
• sterilisation involves cutting or tying the fallopian tubes or sperm duct to stop sperm and egg meeting.
• some women require hormones such as FSH or LH to stimulate ovulation
• IVF (in vitro fertilisation) involves collecting eggs from a female and fertilising them in a lab, after which implanting them into the female's uterus