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What role do hormones play in human reproduction? - OCR 21st CenturyHormonal methods of contraception

Hormones are vital to enable sexual reproduction in humans. There are a range of hormones that interact to cause puberty in males and females, and to prepare a woman鈥檚 reproductive system for pregnancy.

Part of Biology (Single Science)The human body - Staying alive

Hormonal methods of contraception

is naturally controlled by . Scientists understand the role of hormones in the menstrual cycle and fertility so well, that they have been able to develop medication to artificially control fertility, using hormonal forms of contraception.

Oral contraceptives

Contraceptive pills
Figure caption,
Contraceptive pills

The oral contraceptive, which is known as the pill, contains or . These hormones inhibit the production of , so eggs cannot mature and ovulation does not take place.

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. The pills also do not protect against sexually transmitted . Modern pills contain much less oestrogen.

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