Define contraception. Describe methods of contraception that involve (1) barriers, (2) chemicals, (3

Contraception is defined as the deliberate use of artificial methods or other techniques to prevent pregnancy as a consequence of sexual intercourse.

An example of barrier methods is usage of a condom. Any contraceptive devices that prevent fertilization by keeping sperm from reaching the egg. The sperm are either physically blocked from entering the uterus of they are spoiled by a chemical before they can reach the egg.

An example of chemical is the usage of spermicide.

An example of hormones is the birth control pill, which stops ovulation in women.

Prevention of implantation is considered hormonal. The progestin and IUD change the uterine lining, preventing implantation in the rare case that fertilization occurs. The progestin released by the hormonal IUD prevents fertilization by making the mucus in the cervix thick and sticky, so sperm can't get through to the uterus. The progestin and IUD change the uterine lining, preventing implantation in the rare case that fertilization occurs.