Oral sex and STIs

Oral sex means using the mouth, lips, or tongue to stimulate a partner’s genitals. There are different forms of oral sex. Oral-vaginal sex (commonly known as “going down” or “eating someone out”) involves using the mouth and tongue to stimulate the labia, vagina and clitoris, or vulva. Oral-penile sex (commonly known as a blowjob) involves using the mouth and tongue to stimulate the penis and/or testicles. Oral-anal sex (commonly known as rimming) involves using the mouth and tongue to stimulate the anus.

Although it was initially believed that the risk of transmitting STIs during oral sex was not possible, this is not true. You can also transmit STIs during oral sex without the protection of a dental dam or condom. However, the chance of transmitting STIs is smaller during oral sex compared to unprotected vaginal or anal sex.

STIs are transmitted by a virus or bacteria in the blood, semen, vaginal fluid, precum, or fluid from blisters or ulcers on the mucous membrane of someone who is infected with an STI (Venereal Diseases and STIs, 2022). Mucous membranes are located in different places in and on the body. The most common are the mucous membranes around the genitals (vagina and penis), mouth and throat, anus, nose, and eyes. When there is contact between the mucous membranes and infected body fluids (semen, vaginal fluid, precum, etc), STIs can be transmitted without you knowing it.

Oral Sex and Chlamydia and Gonorrhoea

When you have oral sex (oral-vaginal, oral-penile or oral-anal) without the protection of a condom or dental dam, you run the risk of contracting the bacterial STIs chlamydia and gonorrhoea. During oral sex, the mucous membranes of the mouth and throat come into contact with the mucous membranes of the vagina, penis and/or anus. Through this contact, the bacteria can be passed between partners, transmitting an STI. Gonorrhoea is more often transmitted through oral sex because it is more contagious than chlamydia. In contrast to chlamydia, a gonorrhoea infection in the throat can cause symptoms. These symptoms can consist of swollen glands, inflamed tonsils, or pain in the throat or when swallowing.

Oral sex and Syphilis

Giving oral sex to a partner with a syphilis sore on the genitals or anus, or receiving oral sex from a partner with a syphilis sore on their lips, mouth, or throat can cause syphilis. This STI is transmitted through damaged mucous membranes on the genitals and in the mouth through which the bacteria can enter the body. For example, a small cut or wound. Syphilis is most common in men who have sex with men (MSM). If you have symptoms that could indicate an oral STI, it is better not to have oral sex unless you can use a dental dam or condom.

Oral Sex and HIV

While rare, HIV can be transmitted orally if infected body fluids (semen, vaginal fluid, or blood) are able to enter the bloodstream via cuts, scratches, or sores in the mouth. This means that the risk of transmitting HIV during oral sex is lower if ejaculation in the mouth does not occur or the receiving partner is not menstruating. If you already have other STIs, you have a greater chance of contracting HIV. This has to do with the fact that other STIs can cause small tears in the mucous membranes, which increases the risk of HIV transmission. To lower your risk, always pay close attention to wounds, cracks, blisters, and sores in and around the anus, mouth and genitals when you have oral sex, and do not have unprotected oral sex if you have bleeding gums or sores in your mouth. In addition, make efforts to ensure that no semen, vaginal fluid, or blood ends up in your mouth by using a condom or dental dam.

Oral sex and Hepatitis B

You are less likely to transmit hepatitis B during oral sex because infected body fluids (blood, vaginal fluids, cum, pre-cum, etc.) must enter the bloodstream. However, you should pay attention to wounds in and around the mouth, vagina, penis, or anus during oral sex.

How can I prevent STIs during oral sex?

To prevent contracting an STI during oral sex, it is wise to use a condom or dental dam. There are special condoms on the market with added flavors that are made specifically for oral-penile sex. When performing oral-vaginal or oral-anal sex you can use a dental dam or a cut-open condom to protect yourself. To use a cut-open condom, cut the condom along the long side and place it over the genitals before oral sex. Condoms are also always recommended during vaginal or anal sex. Don’t forget to always use extra lubricant during anal sex, as a lack of lubrication increases the risk of tears or cuts that can transmit STIs.

Do you want to find out what your risk of STIs is and which STI test is best to perform? Then fill in our STI Test Guide now!

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