Is oral sex less risky than intercourse?

Be cautious with cold sores

Cold sores are pretty common. You know that slightly tingly, sore spot you get just at the top of your lip that lasts for a week or two? That's a cold sore. It's caused by a tiny virus called herpes simplex. But what's that got to do with oral sex?

Well, if you're a man receiving a blow job (fellatio) and your partner has a cold sore on their mouth, it can spread to your penis. And then every now and then, perhaps every few months, you might get really painful spots on your genitalia that last for a couple of weeks. That's called genital herpes.

Similarly if you're a woman and receiving oral sex (cunnilingus) from a partner who has a cold sore on their lip, it can spread to you too and give you really painful, dark spots on the outside of your vagina. The spots appear from nowhere every few months and last for a couple of weeks. That's genital herpes too.

Genital herpes is actually pretty common: about 1 in 10 people carry the virus inside them, sometimes without knowing. Of those 10%, about a third will have an outbreak of genital herpes every so often, but two thirds will never know they've got it - either because the symptoms are so mild or they never get an outbreak in the first place.

If you think you've got genital herpes (really painful spots on your penis or vagina) go to see a doctor. If your GP or sexual health clinic confirms the diagnosis there are good medications that can stop that current outbreak. But unfortunately there's no medicine yet that can eliminate the herpes virus entirely from your system.

What can you do to stop yourself getting genital herpes? Well, if you have a penis, use a condom (even for oral sex). That's right. Condoms. For oral sex. And if you have a vagina and you're going to receive oral sex from someone with a cold sore, just don't.

Cold sores are really contagious if the person has an active one on their lip; you're bound to catch it if you kiss them or if they give you oral sex. And unfortunately, even if they haven't got a cold sore right now, but have had one in the past, there's a small chance you can catch the virus from them.

Can you catch HIV from oral sex?

HIV is mainly spread through unprotected sexual intercourse. So use condoms. The risk of catching HIV from giving or receiving oral sex is very small, but isn't zero. Let's go through the facts:

If you're a man receiving oral sex from someone with HIV, there is a tiny risk of catching it if you have a cut on your genital area, or if the person giving you oral sex has a cut in their mouth. So it's pretty unlikely really.

If you're giving oral sex to a man who is HIV positive, don't let him ejaculate in your mouth: almost all cases of someone catching HIV from giving a blow job to a man with HIV have been when the man has ejaculated in the person's mouth.

If you're a woman receiving oral sex from someone who is HIV positive, there is only a tiny risk of catching it from them: mainly if they have cuts or abrasions on their mouth and you too have cuts or abrasions on your vaginal area. So it's pretty unlikely.

If you're giving oral sex to an HIV positive woman, the risks are again very small unless she is on her period. Then sometimes the blood from her period will contain the HIV virus and you could catch it if you have cuts or abrasions in your mouth.

Bear in mind that if the HIV positive person is on effective treatment and has what's called an 'undetectable viral load' then a recent study has shown that the risk of catching HIV from them is practically zero.

The mouth cancer link

Actor Michael Douglas, perhaps best known for his outstanding performance in the 1985 adventure The Jewel of the Nile, drew attention a few years ago: he was diagnosed with cancer at the back of his mouth (he's since been treated successfully and is entirely well). He made headlines when he suggested the cancer had been caused by giving oral sex to his famous and no less talented wife, Catherine Zeta-Jones.

Was did he mean? He was referring to a virus called human papillomavirus (HPV for short) which scientists have discovered can actually cause some kind of cancers: cervical cancer, penile cancer and oropharyngeal cancer. The theory is that he may have caught the virus from the genital area of a woman, which led to him developing cancer of the throat.

Nowadays, in the western world, teenage girls are offered a vaccination against the HPV virus which has cut the number of people who are developing those cancers.

In fact Michael Douglas later changed his story, confirming that he did in fact have tongue cancer (which is slightly different)! The good news is he's made a full recovery. But it's important to know the main causes of throat cancer and tongue cancer are smoking and drinking too much alcohol (oral sex is not a recognised risk factor).

In summary

All we're saying is, don't receive oral sex from someone who has a cold sore; the risk of catching HIV from oral sex is very low; and if in doubt ... use condoms.