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Chances of Getting an STD: Separating Myths from Facts

Sexually transmitted diseases (STDs) are diseases that result from sexually transmitted infections (STIs). The terms are often used interchangeably, but technically speaking, the virus or condition that is spread from person to person is typically an STI. If the infection (STI) leads to symptoms, which doesn’t always happen, it becomes an STD. 

Although STIs are fairly common and widely discussed, there’s also a lot of misinformation out there. Because of that, it can be hard to get the real facts about STIs. This article provides clear answers about the chances of getting an STD from different types of sexual encounters.

Chances of getting an STD from oral sex

Oral sex involves using the mouth, tongue, or lips to sexually stimulate a partner’s vagina, anus, or penis. Oral sex is common among sexually active people of all genders and orientations. 

Many STIs and other infections can be spread through oral sex. Sexual contact with a partner who has an STI can lead to an infection in the throat, mouth, rectum, or genitals. 

The chances of getting an STD from oral sex depend on a variety of factors including:

  • The specific type and severity of the STI
  • The prevalence of STIs in the population
  • The use of protection

In general, there are some key things to remember about oral sex and the risk for STIs. It’s possible to contract certain STIs in the throat or mouth from giving oral sex to a partner if they have an anal/rectal or genital infection.

It’s also possible to contract some STIs in the vagina, rectum, or anus while getting oral sex from a partner who has a throat or mouth infection. STIs aren’t limited to one area of the body, either, so an infection is possible in more than one region at the same time (e.g., in the genitals and in the throat).

It’s important to remember that if the other person has an STI, there is a chance of getting an STD from oral sex even if they aren’t showing any signs or symptoms of an active infection. In some cases, symptoms just don’t present themselves. And since several STIs transmitted through oral sex can spread to other parts of the body if left untreated, regular STI testing is essential.

STIs that can be spread through oral sex are:

  • Chlamydia
  • Gonorrhea
  • Syphilis
  • Herpes
  • Human immuno-deficiency virus (HIV)
  • Human papillomavirus (HPV)
  • Trichomoniasis

Apart from these STIs, other infections including hepatitis A, intestinal parasites like amebiasis, and shigella may spread through oral–anal contact.  

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Factors that increase the chances of getting an STD from oral sex

The factors that may increase the chances of getting an STD from oral sex include:

  • Poor oral health, including bleeding gums or gum disease, tooth decay, and oral cancer 
  • Sores on the genitals or in the mouth can increase the chances of getting an STD from oral sex, as they are open wounds.
  • Exposure to ejaculate or pre-ejaculate of a partner who is infected with an STI 

How to prevent transmission of an STI during oral sex

Using a dental dam, condom, or any other barrier method can reduce the chances of getting an STD from oral sex. 

  • Fully covering the penis with a latex condom (or polyurethane in case of a latex allergy) during oral sex can help prevent the transmission of an STI. 
  • For oral sex on the anus or the vagina, using a dental dam can help prevent the transmission of an STI. It’s possible to make a dental dam by simply cutting a square out of a condom and placing it between the mouth and the partner’s anus or vagina.

Chances of getting an STD from a one-night stand

The chances of getting an STD from a one-night stand depend on whether it was protected or unprotected sex. The chances of getting an STD from one unprotected encounter with a partner who is infected with syphilis, gonorrhea, or chlamydia are about 30 percent. Since these infections can lead to serious health concerns if not treated promptly, it’s important to understand the risk that unprotected sex poses. To reduce the risk of transmission, always use a reliable form of sexual protection like latex condoms.

Do condoms prevent STDs 100 percent?

When used correctly and consistently, condoms are highly effective at preventing STIs that are transmitted through bodily fluids, including chlamydia and gonorrhea. They also effectively prevent the spread of HIV. They provide less protection against infections spread through skin-to-skin contact, such as herpes, HPV, and syphilis.

So, can you catch an STD with a condom? Yes. Abstinence is the only method that is 100 percent effective at preventing all STIs. But among people who use condoms for protection, the chances are greatly reduced.

Here are some tips for getting the most protection from using condoms:

  • Read the package label of the condom before using it.
  • Choose condoms with a label that says they prevent disease.
  • Use a new condom each time you have sex.
  • Store condoms in a cool, dry place, as heat may weaken them and reduce their effectiveness.
  • When using lubricant with condoms, always choose a water-based one; oil-based lubricants like baby oil, petroleum jelly, and cold cream can weaken the condom.

Choosing the right type of condom to prevent STIs

Always read the package label and look for the following two things:

  1. The condoms must be made of latex (or polyurethane in case of a latex allergy). Tests show that both polyurethane and latex condoms (including female condoms) may prevent the transmission of hepatitis and HIV. Condoms made of lambskin may not offer the same protection. Organic condoms are not fit for this purpose as they have pores wide enough for the viruses to pass through and enter the body. 
  2. The package label must say that the condoms can prevent disease. If there is nothing mentioned on the package about prevention of disease, the condoms may not be tested to prevent the spread of STIs.

STI testing: When do you need it?

It’s a good idea for anyone who is sexually active to get tested for STIs. This is particularly important in the following scenarios:

  • When entering into a new relationship
  • When not using a barrier method, such as condoms, while having sex
  • If either partner is having sex with multiple partners
  • If either partner is experiencing symptoms and signs that suggest they may have an STI
  • In cases of sexual assault

Anyone who is pregnant or may become pregnant needs to be tested for STIs, as they can affect the fetus. The health care provider may provide screening for STIs at the initial prenatal visit

At the end of the day, it’s important to remember that the only way to be completely protected from STIs is to abstain from sex. Any kind of sexual encounter with another person carries a chance of getting an STD. 

Many STIs including chlamydia, gonorrhea, syphilis, herpes, HIV, HPV, and trichomoniasis can be spread through oral sex. Using a dental dam or condom can reduce the chances of getting an STD from oral sex. The chances of getting an STD from a one-night stand are also high if protection isn’t used. Condoms are effective at preventing many of the most common STIs.

“STD Risk and Oral Sex.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 27 Feb. 2020, www.cdc.gov/std/healthcomm/stdfact-stdriskandoralsex.htm.

“Prevention - STD Information from CDC.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 30 Mar. 2020, www.cdc.gov/std/prevention/default.htm.

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