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Sexually transmitted infections (STIs)

A sexually transmitted infection, or STI, is an infection passed from person to person through sexual contact. You can get and pass STIs through vaginal, anal, or oral sex or during genital touching. You or your partner can have an STI and not know it because you may have no symptoms. If you do have symptoms, they might include a discharge from your penis, sores on your penis, pain and swelling in your testicles, and burning in your urethra.

STI rates are very high in the United States, where there are an estimated 19 million new cases each year. HIV is an STI that is especially dangerous. Syphilis, another STI, has been spreading more in recent years, and if untreated, can harm your brain, heart, and other parts of your body.

Certain STIs are more common among men who have sex with men. If you have sex with men, talk to your doctor about steps you can take to protect your health, including getting vaccinated for hepatitis A and hepatitis B.

How to use a condom correctly

  1. Keep condoms in a cool, dry place.
  2. Check to make sure the wrapper isn't torn. Check the date to make sure the condom is not too old. Open carefully.
  3. Examine condom: Don't use if it is gummy, brittle, or discolored, or has a tiny hole.
  4. Put on the condom as soon as the penis is erect, but before it touches the vagina, mouth, or anus.
  5. Don't use oil-based lubricants like baby oil, lotions, or petroleum jelly because they can weaken the condom.
  6. After sex, pull out your penis while still erect, holding the condom firmly at the base of the penis so it does not slip off.
  7. Use a new condom if you want to have sex again or in a different way.

All men should take steps to lower their risk of STIs. You can:

  • Avoid having sex. Abstain from having vaginal, oral, or anal sex.
  • Be faithful. Having sex with one uninfected partner who has had sex only with you will keep you safe from STIs.
  • Use condoms correctly and every time you have sex. Use male latex condoms for vaginal, anal, or oral sex. Use polyurethane if you or your partner is allergic to latex. "Natural" or lambskin condoms don't protect against STIs. Male condoms are highly protective when used correctly. Female condoms also may offer protection, but more research is necessary. For oral sex, dental dams also might offer some protection.
  • Know that certain birth control methods don't protect against STIs. Birth control methods including the pill, shots, implants, IUDs, diaphragms, and spermicides will not protect you from STIs. If your partner uses one of these methods, be sure to also use a latex condom or dental dam correctly every time you have sex.
  • Talk with your sex partner(s) about STIs and using condoms before having sex. Setting the ground rules about testing and condom use will avoid future misunderstandings. It's up to you to make sure you are protected.
  • Get tested. If either you or your partner has now or has had other sexual partners in the past, get tested for STIs before having sex. If you have an STI, let your sexual partner(s) know so you and your partner(s) can get treatment. Otherwise, the STI can get passed to others or back to you. You can learn more about specific STIs at the Centers for Disease Control and Prevention website.

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Content last updated: January 10, 2011.

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