Contraception refers to methods or devices used to prevent pregnancy. There are different types of contraception, including hormonal methods and non-hormonal methods.
Some methods of contraception also provide protection against sexually transmitted infections (STIs).
Hormonal methods of contraception
Hormones, such as oestrogen and progesterone, play an important role in fertilisation. Some methods of contraception use hormones to prevent the release of the egg during the menstrual cycle.
Oestrogen inhibits the production of FSH, preventing the eggs from maturing and being released from the ovaries.
Progesterone inhibits ovulation and produces a thick mucus, which stops any sperm from reaching the egg.
Some examples of hormonal methods of contraception include:
Combined pill – An oral contraception that contains both oestrogen and progesterone
Progesterone-only pill – An oral contraception that only contains progesterone
A person taking oral contraceptives must remember to take them on a daily basis, or the effectiveness will decrease.
Skin patch, implant or injection – These release progesterone slowly, inhibiting the maturation and release of eggs. The skin patch sticks to the skin and the implant goes under the skin on the upper arm. A benefit of these methods is that the user does not need to remember to take the contraception on a daily basis
Intrauterine device (IUD) – A T-shaped device that goes into the uterus and stops an egg from implanting. There are IUDs made of plastic that release progesterone, and copper IUDs that incapacitate sperm.
Hormonal methods of contraception can be very effective, but they may come with side effects associated with them. For example, mood swings, weight gain, changes in blood pressure and irregular periods.
Certain hormones can be used to enhance fertility, increasing the chances of pregnancy.
Non–hormonal methods of contraception
These methods do not contain hormones and they stop the sperm from reaching the egg.
Condom (barrier method) – Worn over the penis during sexual intercourse, it prevents sperm from entering the vagina. Female condoms are also available. Condoms are the only contraceptives that prevent both pregnancy and the transmission of STIs.
Diaphragm (barrier method) – A shallow, dome-shaped cup placed over the cervix to trap sperm. Adding spermicide to the diaphragm makes it more effective at preventing pregnancy.
Spermicidal agents – Kill or disable sperm.
Surgical methods (sterilisation) – For males, the procedure involves cutting and tying the sperm ducts (a vasectomy) to prevent sperm from leaving the penis. In females, the fallopian tubes (oviducts) can be cut or tied to prevent eggs from travelling from the ovaries to the uterus.
Natural method – Avoiding sexual intercourse during the most fertile stages of the menstrual cycle can reduce the likelihood of pregnancy.
Abstinence – Choosing to refrain from all forms of sexual intercourse is the only contraceptive method that guarantees 100% effectiveness in preventing pregnancy.