Safe Sex

Sexual practices that minimize your risk of contracting sexually transmitted infections

One of the hazards of sexual contact is exposure to certain infections. These range from minor problems, such as pubic lice, to life-threatening disorders, such as HIV infection (see HIV infection and AIDS). Some disorders, such as genital herpes, genital warts, and gonorrhoea, are almost always transmitted by sexual contact and are known as sexually transmitted infections (STIs). Others, such as hepatitis B and C (see Acute hepatitis) and HIV infection, may be transmitted by other means as well as through sex. For example, people who inject drugs and share needles with others risk infection with HIV or hepatitis. Some disorders, such as scabies, are transmitted by physical contact and are common among people living in overcrowded conditions and among schoolchildren. These disorders may also be transmitted through sex.

Assessing the risks

It is important to assess your risk of exposure to STIs so that you can make informed choices about sexual activity. You need to understand how infection is spread and know which sexual activities carry the highest risks. If you think you are likely to be exposed to infection, or if you are not sure what your own risk might be, you should use a condom (see Using contraceptives) or avoid sex. You should try to ensure that you and your partner do not have unprotected sex until your relationship is well established and monogamous and both of you are known to be free of disease.

High-risk activities

Diseases such as hepatitis B and C and HIV infection may be spread by contact with semen, blood, or vaginal secretions. Other disorders, such as genital warts and genital herpes, are transmitted by contact with a wart or sore. The areas most vulnerable to infection are the skin of the genitals and mucous membranes such as the lining of the vagina, anus, mouth, and urethra.

The sexual activities that pose the highest risks are those in which the mucous membranes could be damaged, allowing infections from body fluids or body parts to enter the bloodstream. Vaginal, anal, and oral intercourse that involves penetration, and in which partners do not use a condom, are the activities carrying the highest risks. Anal penetration can be particularly hazardous because the lining of the anus and rectum is easily damaged.

Sexual history

The risk of exposure to STIs increases with the more sexual partners you have and the more times that you practise unsafe sex. A monogamous relationship with someone whom you know has been screened and found free of disease carries the lowest risk. You may be more vulnerable if your partner has had sex with someone else and has not told you, particularly if you do not use a condom with that partner. You or your partner may already have an STI but have no symptoms. For example, chlamydial infections affect both sexes but often cause no symptoms in women. In both sexes, infection with genital warts is followed by a latent period of about 9 months when you have no symptoms but are still infectious. Casual sex without using a condom carries most risk because you are unlikely to know if your partner is infected.

Some STIs are particularly prevalent in certain groups of people. For example, HIV infection is more common among people living in some parts of Africa and Asia, prostitutes, people who inject recreational drugs and share needles, and people who have unprotected anal sex. You may run a higher risk of infection if you have unsafe sex with a person from one of these groups.

Gonorrhoea organisms

This highly magnified view shows the bacteria that cause gonorrhoea, Neisseria gonorrhoeae, which may be found in genital, rectal, and throat secretions.

What you can do

Condoms are able to protect you from infections that are transmitted during sexual intercourse. However, they do not protect you from contact with sores or warts on uncovered areas of the body or from pubic lice or scabies.

If you choose not to use condoms, make sure that neither you nor your partner has an infection. Discuss your past sexual contacts honestly, particularly if either of you is in a high-risk group. If you suspect that you have been exposed to infection, arrange to have a screening test at a clinic that specializes in treating STIs. With HIV infection, there is a latent period of at least 2–3 months between acquiring the infection and the time when the antibody to the virus can be detected in the test. For this reason, many clinics advise using condoms for the first 3 months of a new relationship before having an HIV test.

Once you and your partner are sure that you are free from STIs, the most effective way to protect yourselves is by remaining monogamous. If you do have sexual intercourse with other partners, make sure that you use condoms. If you are not using condoms and develop an STI, use condoms until you have been treated and are free of disease or abstain from penetrative sex. Both you and your partner should be treated at the same time to avoid the risk of reinfecting each other, and you should both be free of disease before you stop using condoms. Sexual activities that carry a relatively low risk of infection include kissing your partner’s mouth (or body areas other than the genitals) and mutual masturbation by hand. The activities that have little or no risk are those that do not involve contact with your partner’s genitals.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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