Many sexually transmitted diseases (STIs) can be spread through oral sex. Using a condom, dental dam or other barrier method each and every time you have oral sex can reduce the risk of giving or getting an STI.

Fast Facts
Many sexually transmitted diseases (STIs) can be spread through oral sex.
Using a condom, dental dam or other barrier method each and every time you have oral sex can reduce the risk of giving or getting an STI.
Although oral sex may carry a lower risk for spreading HIV than other forms of sex, repeated unprotected exposures may increase risk of transmission.
What is Oral Sex?
Oral sex involves using the mouth, lips, or tongue to stimulate the penis (fellatio), vagina (cunnilingus), or anus (anilingus) of a sex partner. The penis and testicles and the vagina and area around the vagina are also called the genitals or genital area.

How Common is Oral Sex?
See "How common is oral sex?" for statistics in this image.
Oral sex is commonly practiced by sexually active adults. Oral sex can happen between heterosexual (straight) and same-sex (gay or lesbian) couples. More than 85% of sexually active adults aged 18-44 years reported having had oral sex at least once with a partner of the opposite sex. A separate survey conducted during 2007-2010 found that 33% of teenage girls and boys aged 15-17 years reported having had oral sex with a partner of the opposite sex.

Can STIs Be Spread During Oral Sex?

Many STIs, as well as other infections, can be spread through oral sex. Anyone exposed to an infected partner can get an STI in the mouth, throat, genitals, or rectum. The risk of getting an STI from oral sex, or spreading an STI to others through oral sex, depends on a number of things, including

The particular STI.
The sex acts practiced.
How common the STI is in the population to which the sex partners belong.
The number of specific sex acts performed.
In general:

It may be possible to get some STIs in the mouth or throat from giving oral sex to a partner with a genital or anal/rectal infection, particularly from giving oral sex to a partner with an infected penis.
It also may be possible to get certain STIs on the penis (and possibly the vagina, anus or rectum) from getting oral sex from a partner with a mouth or throat infection.
It’s possible to have an STI in more than one area at the same time, for example in the throat and the genitals.
Several STIs that may be transmitted by oral sex can then spread throughout the body of an infected person.
STIs can be spread to a sex partner even when the infected partner has no signs or symptoms. If you are infected with an STI, you might not know it because many STIs may have no symptoms.
Which STIs Can Be Passed On from Oral Sex?
Chlamydia
Gonorrhea
Syphilis
Herpes
HPV (human papillomavirus)
HIV
Trichomoniasis

Chlamydia

Risk of infection from oral sex:
Giving oral sex to a man with an infected penis can result in getting chlamydia in the throat.
Giving oral sex to a woman with an infected vagina or urinary tract may result in getting chlamydia in the throat.*
Giving oral sex to a man or woman with an infected rectum might result in getting chlamydia in the throat.*
Getting oral sex on the penis from a partner with chlamydia in the throat can result in getting chlamydia of the penis.
Getting oral sex on the vagina from a partner with chlamydia in the throat might result in getting chlamydia of the vagina or urinary tract.*
Getting oral sex on the anus from a partner with chlamydia in the throat might result in getting chlamydia in the rectum.*

* Statements followed by an asterisk (*) have not been well studied.

Areas of initial infection:
Throat
Genitals
Urinary tract
Rectum
Initial signs and symptoms of infection:
Most chlamydia infections in the throat have no symptoms. When symptoms are present, they can include a sore throat.
Many genital, urinary tract, or rectal chlamydia infections have no symptoms. When symptoms are present, they can include:
Discharge from vagina or penis (discharge from the vagina may be bloody).
Burning feeling when urinating.
Painful or swollen testicles.
Rectal pain or discharge
Treatment:
Chlamydia can be cured with the right medicine.
The sex partners of a person with chlamydia should also be tested for infection. Those who are diagnosed with chlamydia should not have sex until they and their sex partners have completed treatment.
If left untreated, throat infections:
Can be spread to uninfected sex partners, particularly by performing oral sex on a male partner’s penis.
If left untreated, genital, urinary and/or rectal infections:
Can be spread to uninfected sex partners.
In women:
Can cause pelvic inflammatory disease (PID), which can lead to chronic pelvic pain, infertility, and ectopic pregnancy (a pregnancy in the fallopian tube or elsewhere outside of the womb).
In pregnant women:
Might result in premature birth or low birth weight in babies.
Can be spread to the baby during delivery, and can cause chlamydia infection in the eyes or infection of the respiratory tract that can develop into pneumonia.
In men:
Can cause epididymitis, a painful condition of the ducts attached to the testicles that may lead to ductal scarring.
In both men and women:
May increase risk of getting HIV infection.
Might increase risk of spreading HIV to sex partners.
May cause a reaction (reactive arthritis) throughout the body that can lead to arthritis (joint pain), conjunctivitis (pink eye), and/or a rash on the soles of the feet or elsewhere.
In addition to the STIs above, other infections such as hepatitis A virus, Shigella and intestinal parasites (amebiasis) can be spread through giving oral sex on the anus.

Is Oral Sex Safer than Vaginal or Anal Sex?

Many STIs can be spread through oral sex. However, it is difficult to compare the exact risks of getting specific STIs from specific types of sexual activity. This is partly because most people who have oral sex also have vaginal or anal sex. Also, few studies have looked at the risks of getting STIs other than HIV from giving oral sex on the vagina or anus, compared to giving oral sex on the penis.
Studies have shown that the risk of getting HIV from having oral sex with an infected partner (either giving or getting oral sex) is much lower than the risk of getting HIV from anal or vaginal sex with an infected partner. This may not be true for other STIs – in one study of gay men with syphilis, 1 out of 5 reported having only oral sex.
Getting HIV from oral sex may be less likely than vaginal or anal sex, but it still carries risk. If you are having oral sex you should still protect yourself. Repeated unprotected oral sex exposure to HIV may represent a considerable risk for spread of HIV, as well as other STIs for which the risk of spread through oral sex has not been as well studied.
It is possible that getting certain STIs, such as chlamydia or gonorrhea, in the throat may not pose as great a threat to an infected person’s health as getting an STI in the genital area or rectum. Having these infections in the throat might increase the risk of getting HIV. Having gonorrhea in the throat also may lead to spread of the disease throughout the body. In addition:
Having infections of chlamydia and gonorrhea in the throat may make it easier to spread these infections to others through oral sex. This is especially important for gonorrhea, since throat infections are harder to treat than urinary, genital or rectal infections.
Infections from certain STIs, such as syphilis and HIV, spread throughout the body. Therefore, infections that are acquired in the throat may lead to the same health problems as infections acquired in the genitals or rectum.
Mouth and throat infections by certain types of HPV may develop into oral or neck cancer.
What May Increase the Chances of Giving or Getting an STI through Oral Sex?
It is possible that certain factors may increase a person’s chances of getting HIV or other STIs during oral sex if exposed to an infected partner, such as:

Having poor oral health which can include tooth decay, gum disease or bleeding gums, and oral cancer.
Having sores in the mouth or on the genitals.
Being exposed to the “pre-cum” or “cum” (also known as pre-ejaculate or ejaculate) of an infected partner.
However, no scientific studies have been done to show whether or not these factors actually do increase the risk of getting HIV or STIs from oral sex.

What Can You Do to Prevent STI Transmission During Oral Sex?
You can lower your chances of giving or getting STIs during oral sex by using a condom, dental dam or other barrier method each and every time you have oral sex.

For oral sex on the penis:
Cover the penis with a non-lubricated latex condom.
Use plastic (polyurethane) condoms if you or your partner is allergic to latex.
For oral sex on the vagina or anus:
Use a dental dam.
Cut open a condom to make a square, and put it between the mouth and the partner’s vagina or anus.
The only way to avoid STIs is to not have vaginal, anal, or oral sex.

If you are sexually active, you can do the following things to lower your chances of getting an STI:

Being in a long-term mutually monogamous relationship with a partner who is not infected with an STI (e.g., a partner who has been tested and has negative STI test results).
Using latex condoms the right way every time you have sex.
It’s important to remember that many infected individuals may be unaware of their infection because STIs often have no symptoms and are unrecognized.

If you are sexually active, you should get tested regularly for STIs and HIV and talk to your partner(s) about STIs. If you think you might have an STI, stop having sex and visit your doctor or clinic to get tested. There are free and low-cost options for testing in your area. External It is important that you talk openly with your health care provider about any activities that might put you at risk for an STI, including oral sex.