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Ask Dr. K

I have three questions. I hope you can help. How dangerous is cumming in the mouth for both the receiver and giver? What about anal sex without a condom, but taking out your penis before cumming? And thirdly, if you are cured of an STD, can you still get infected in the future?

Okay, let's answer your questions one by one. Oral sex and semen swallowing carry a very, very low risk of HIV infection. While some recent studies have suggested it may be zero, there are definitely case reports and individual experiences that support that HIV can be transmitted through oral sex, although it seems to be rare. It may be possible to take this concept further and reduce an already low risk activity to a lower risk one, the thinking would be that no semen would be safer than some, but truthfully there is no scientific proof in this area yet. There seems to be even a lower risk of transmission in people who receive oral sex and I am not aware of any case reports that document getting oral sex as a way to get HIV.

On to your next question. Receptive anal sex is the riskiest form of sex. HIV is in pre-cum -- the fluid before ejaculation, so even if the inserter pulls out, infection is possible. Men do get infected from both anal receptive and anal insertive sex but anal receptive sex is about 10 times more risky. Some numbers that some folks quote is 1 in 50 vs. 1 in 500 chance of infection from receptive vs. insertive anal intercourse.

Condoms work very well to reduce the risk of transmission from an infected partner to an uninfected one. Of course if both partners have recently tested negative and had not had any new partners since their tests, then the risk of transmission is very, very low.

And lastly, if you are treated once for an STD like gonorrhea, syphilis or chlamydia, it does NOT protect you from future infections. We see patients every day with new STDs that they have had before. Each germ is a little different and your immune system does not protect you from future infections.

To your health,
Dr. K

Last modified on Tuesday, June 03, 2008.
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