Transmission from breastfeeding

HIV is present in breast/chest milk – a bit like viral load in blood.

The risk of transmission comes from HIV in the milk gets through the lining of the baby’s stomach and intestines.

The gut (stomach/belly) in a young baby is new and more fragile. It is much easier for HIV to get through compared to an adult. (So breat/chest milk is not a risk for adults).

It is unclear whether damage to the gut of the baby increases this risk. This might happen with the early introduction of other foods, particularly solid foods, or water. However, this research was done in women who were not on ART.

In the UK, women living with HIV are mostly recommended to formula feed. This is the best way to protect babies from HIV. But, women living with HIV who wish to breastfeed, can now be supported to do so safely.

Please speak to your doctor if you are thinking of or planning to breastfeed so they can advise and support you. 

The most important thing about vertical transmission is not how it happens, but how we can stop it.

Last updated: 1 November 2023.