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Coordination and control - The endocrine system - OCR Gateway Hormonal methods of contraception

The endocrine system secretes hormones into the bloodstream from glands throughout the body. Hormones produce an effect on specific target organs in the body.

Part of Biology (Single Science)Organism level systems

Hormonal methods of contraception

Oral contraceptives

is controlled by , so fertility can be controlled using hormonal forms of contraception.

The oral contraceptive, which is known as the pill, contains or . These hormones inhibit the production of , and eggs cannot mature.

Contraceptive pills
Image caption,
Contraceptive pills

Benefits and risks

Oral contraceptives are more than 99% effective if taken correctly and can reduce the risk of certain cancers.

However, there are possible side effects, such as changes in weight, mood and blood pressure due to high levels of oestrogen. Modern pills contain much less oestrogen.

Contraceptive injections, implants or skin patches contain slow release progesterone to inhibit the maturation and release of eggs.