Recently diagnosed with HIV: sex

Mareike Günsche |

Key points

  • Most people living with HIV continue to have sex and form relationships.
  • If you use condoms properly, you will not pass HIV on to a sexual partner.
  • If you are taking HIV treatment and have an undetectable viral load, you will not pass HIV on to a sexual partner.
  • People living with HIV can have children who don’t have HIV.

Sex when you have HIV

Having HIV can affect people’s feelings about sex in many different ways.

Some people become anxious about passing HIV on, or feel less desirable. While some people go off sex altogether, others need it more. It may be more important than ever to feel wanted or to have moments of intimacy and pleasure.

It’s worth knowing that most people living with HIV continue to have sex and form relationships. If you use condoms properly or take treatment and have an undetectable viral load, you will not pass HIV on to a sexual partner.

Undetectable = untransmittable

Effective HIV treatment prevents the sexual transmission of HIV.

Several large studies have proven that people living with HIV who take HIV treatment and have an undetectable viral load do not pass on HIV to their sexual partners, even when condoms aren’t used.

This is because HIV treatment reduces the amount of HIV in the body. If you have an ‘undetectable viral load’, this means that there is not enough HIV to pass it on to someone else.

This is what is meant when people say that 'undetectable = untransmittable'. This is sometimes shortened to U=U.

When you have had an undetectable viral load for at least six months you can rely on this to protect your sexual partners. Before this, other prevention methods (like condoms) should be used. This is because during the first few months of taking treatment you may still be able to pass HIV on.

Medical experts and organisations around the world agree that U=U. This includes the British HIV Association (BHIVA), which is the professional association for HIV doctors in the UK.

BHIVA says that all people with a sustained undetectable viral load (for at least six months) and good adherence to HIV treatment can be advised that there is no risk of onward transmission of HIV to their sexual partners.

Putting U=U into practice

The good news about 'undetectable = untransmittable' applies equally to men and women, whether cisgender or transgender, to heterosexuals and gay people.

Dr Vanessa Apea shares facts about 'Undetectable equals Untransmittable' (U=U).

It is as relevant for anal sex as it is for vaginal sex. It applies whether or not condoms are being used.

It’s also relevant if you’d like to have a child with a partner who does not have HIV. Once you’ve been undetectable for six months, you can have unprotected sex in order to conceive, without worrying about passing HIV on.

Many people living with HIV say that learning about 'undetectable = untransmittable' is very powerful. It can make sex more relaxed and enjoyable. It might make a difference to how you feel about yourself.

But it might be new information for your sexual partners. You could help by showing them this booklet. It may take some time for them to understand and trust what they are being told.

Condoms and contraception

Using condoms is also a good way to stop HIV from being passed on. Condoms prevent body fluids containing HIV from passing from one person to another. Using a water- or silicone-based lubricant makes condoms even safer.

Find out more about U=U in our video we made with animation studio Animade.

When condoms are used consistently and correctly, they are very effective. Nonetheless, the most reliable way to prevent HIV from being passed on is having an undetectable viral load.

Condoms will also protect you from other sexually transmitted infections, which an undetectable viral load cannot do. Using condoms and having an undetectable viral load is a good way to take care of both your health and that of your partners. You can also ask your clinic to give you a regular sexual health check-up.

If you need contraception, you need to tell your doctor about your HIV treatment. Some anti-HIV drugs can interact with the pill and other hormonal contraceptives. Your doctor can help you choose a contraceptive which you can use alongside your HIV treatment.

Transmission facts

If you are taking HIV treatment and have had an undetectable viral load for at least six months, you don’t need to worry about passing HIV on.

But if you’re not yet at that stage or sometimes forget to take your pills, it’s good to be clear about when there is and when there isn’t a risk of passing HIV on to someone else.

Anal and vaginal sex are the most common ways that HIV is passed on.

The risk of transmitting HIV during other sexual activities is much, much lower. Oral sex is considered to be very low risk.

It's impossible for HIV to be passed on through kissing, cuddling or stroking.

There is no risk of passing on HIV during normal social contact. No-one has ever caught HIV from:

  • sharing household items like cups, plates or cutlery,
  • using the same toilet, or
  • breathing the same air as someone with HIV.

PEP (post-exposure prophylaxis)

If you’re worried that you might have just exposed someone to HIV, an emergency treatment called PEP may be available.

This could be useful if you had sex without a condom or if a condom broke. But PEP won’t be necessary if you are taking HIV treatment and your viral load has been undetectable for at least six months.

PEP is a course of anti-HIV drugs that must be started very soon after the risk has been taken – the sooner the better and definitely within 72 hours (three days). It can prevent HIV from being passed on.

PEP is usually available from HIV clinics, sexual health clinics and Accident & Emergency departments.

HIV and the law

You might have already heard about people going to prison for passing on HIV. While it’s important to be aware of this, you should know that the law is only involved in very specific circumstances. So far only around 30 people have been convicted of this in the UK.

In England and Wales, you could be convicted if, at the time you had sex:

  • you knew you had HIV,
  • and you understood how HIV is transmitted,
  • and you had sex with someone who didn’t know you had HIV,
  • and you had sex without a condom,
  • and you definitely transmitted HIV to that person.


undetectable viral load

A level of viral load that is too low to be picked up by the particular viral load test being used or below an agreed threshold (such as 50 copies/ml or 200 copies/ml). An undetectable viral load is the first goal of antiretroviral therapy.

viral load

Measurement of the amount of virus in a blood sample, reported as number of HIV RNA copies per milliliter of blood plasma. Viral load is an important indicator of HIV progression and of how well treatment is working. 


Undetectable = Untransmittable (U=U)

U=U stands for Undetectable = Untransmittable. It means that when a person living with HIV is on regular treatment that lowers the amount of virus in their body to undetectable levels, there is zero risk of passing on HIV to their partners. The low level of virus is described as an undetectable viral load. 

post-exposure prophylaxis (PEP)

A month-long course of antiretroviral medicines taken after exposure or possible exposure to HIV, to reduce the risk of acquiring HIV.


How well something works (in real life conditions). See also 'efficacy'.

However, the law doesn’t require you to always use a condom or to tell all sexual partners that you have HIV.
A conviction can only happen when HIV is passed on. If you have an undetectable viral load or use condoms, HIV won’t be passed on and there shouldn’t be any problems with the law.

In Northern Ireland, the law is similar to that in England and Wales.

But Scottish law is different – a conviction is possible even if HIV was not passed on.

Sometimes, the police have launched investigations when no-one has done anything wrong. If the police start to ask you questions, it’s essential to get expert advice. Call THT Direct on 0808 802 1221.

Thinking about going to the police?

If you are thinking of making a police complaint about the person you think gave you HIV, it’s important to be aware of the possible consequences for you. It’s worth getting advice from an organisation that has experience of these situations. You should give yourself time to think through what’s best for you.

If you do go to the police, they will closely examine your sex life and may contact your previous partners. This may lead to other people finding out that you have HIV. The process can take a lot of time, and it can become difficult to withdraw a complaint.

For more information and advice, call THT Direct on 0808 802 1221.

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