Safe sex is sexual activity engaged in by people who have taken precautions to protect themselves against sexually transmitted infections (STIs) such as HIV/AIDS. It is also referred to as safer sex or protected sex, while unsafe or unprotected sex is sexual activity engaged in without precautions. Some sources prefer the term safer sex to more precisely reflect the fact that these practices reduce, but do not completely eliminate, the risk of disease transmission. In recent years, the term "sexually transmitted infections" (STIs) has been preferred over "STDs", as it has a broader range of meaning; a person may be infected, and may potentially infect others, without showing signs of disease.
Safe sex practices became more prominent in the late 1980s as a result of the AIDS epidemic. Promoting safe sex is now one of the aims of sex education. Safe sex is regarded as a harm reduction strategy aimed at reducing risks. The risk reduction of safe sex is not absolute; for example the reduced risk to the receptive partner of acquiring HIV from HIV seropositive partners not wearing condoms to compared to when they wear them is estimated to be about a four- to fivefold. Although some safe sex practices can be used as contraception, most forms of contraception do not protect against all or any STIs; likewise, some safe sex practices, like partner selection and low risk sex behavior, are not effective forms of contraception.
Safe sex is effective in avoiding STDs only if both parties involved in sexual intercourse agree on it and stick to it. During sexual intercourse using a condom, for example, the male could intentionally pull off the condom and continue penetrating without the female (or male receptive) partner's consent and notice. This is a high risk behavior that betrays trust as well as spreading disease.
Birth control, also known as contraception and fertility control, refers to methods or devices used to prevent pregnancy. Planning and provision of birth control is called family planning. Safe sex, such as the use of male or female condoms, can also help prevent transmission of sexually transmitted infections. Contraceptive use in developing countries has cut the number of maternal deaths by 44% (about 270,000 deaths averted in 2008) but could prevent 73% if the full demand for birth control were met. Because teenage pregnancies are at greater risk of adverse outcomes such as preterm birth, low birth weight and infant mortality, some authors suggest adolescents need comprehensive sex education and access to reproductive health services, including contraception. By lengthening the time between pregnancies, birth control can also improve adult women's delivery outcomes and the survival of their children.
Effective birth control methods include barriers such as condoms, diaphragms, and the contraceptive sponge; hormonal contraception including oral pills, patches, vaginal rings, and injectable contraceptives; and intrauterine devices (IUDs). Emergency contraception can prevent pregnancy after unprotected sex. Long-acting reversible contraception such as implants, IUDs, or vaginal rings are recommended to reduce teenage pregnancy. Sterilization by means such as vasectomy and tubal ligation is permanent contraception. Some people regard sexual abstinence as birth control, but abstinence-only sex education often increases teen pregnancies when offered without contraceptive education. Non-penetrative sex and oral sex are also sometimes considered contraception.