Sperm washing

Visit the Assisted Conception Unit (ACU) at Chelsea and Westminster Hospital for Sperm washing - you can ask your GP to refer you to us.

This service has been developed for couples who wish to have a child where the male partner is HIV positive but the female is HIV negative (referred to as HIV discordant status). The aim is to reduce the risk of HIV transmission by attempting to achieve pregnancy through insemination of sperm washed free of HIV rather than through unprotected intercourse.

The technique used to do this is called sperm washing and rests on the observation that HIV infective material is carried in the fluid around the sperm (seminal fluid) rather than by sperm itself. The technique involves separating the HIV infected seminal fluid from the sperm by centrifugation and ‘washing’. The ‘washed’ sperm is then combined with nutritional fluid, tested for HIV using a sensitive test called a 'PCR' assay and, provided this is negative, inseminated into the female partner when she is ovulating and most likely to become pregnant. In couples with fertility problems washed sperm can be used in other fertility treatments such as IVF.

We were the first clinic in the UK able to offer sperm washing to couples. There are more than 25 clinics worldwide now offering the treatment. The combined results from all these clinics indicates that in more than 5,000 inseminations or other fertility treatments carried out using washed sperm (prepared according to published guidelines), there have been no reported cases of HIV transmission to the female partner or resulting child.

The medication used to treat HIV is now highly effective which has led some couples to ask about the safety of conceiving naturally. Unfortunately, even in men with negative viral loads, semen can still carry HIV, and therefore potentially infect the female partner. The risk of HIV transmission per act of unprotected intercourse from man to woman is still there and it is estimated to be 0.2% or 1 in 500 in couples, even when intercourse is restricted to the time of the month when the woman is ovulating.

We therefore strongly recommend that couples wishing to conceive safely continue to have protected intercourse and use sperm washing as a safer alternative. We do stress however that, despite an excellent safety record for all the clinics using the technique, the method should still be regarded as a risk-reduction treatment and not risk-free as in theory some HIV can still remain in the sperm preparation after washing. We minimise any risk by testing every single sample of sperm we wash for HIV before using it in treatment. The HIV test used however cannot detect extremely low levels of HIV but these levels of HIV are thought to be insufficient to infect the female partner.

If you feel that you do not want to take any risk, no matter how minimal, then you should not consider sperm washing. You may prefer to find out more about artificial insemination by donor sperm, which is a risk-free alternative.

Contact us

General enquiries
020 3315 8585


"My overall experience at the clinic was very good. The staff are welcoming, thorough in their explanations and understanding. They made a scary process more bearable and I would not change clinics for any reason."

"It is a highly professional and developed unit. We are grateful for your dedication and commitments towards a great cause - Thanks."