If a pregnant woman is infected with HIV, she can transmit the virus to her baby during pregnancy, labour and delivery, or breastfeeding. Without treatment, around 15-30% of babies born to HIV-infected women will become infected with HIV during pregnancy and delivery. A further 5-20% will become infected through breastfeeding.

Modern drugs are highly effective at preventing mother-to-child transmission of HIV. When combined with other interventions, including formula feeding, a complete course of treatment can cut the risk of transmission to below 2%. Even where resources are limited, a single dose of medicine given to mother and baby can cut the risk in half.

What drugs should I take?

The drugs that can reduce the risk of HIV transmission from a mother to her baby are called antiretroviral (ARV) drugs. ARVs are the drugs that are taken by people living with HIV to prevent them from becoming ill.
The most important time for an HIV positive pregnant woman to take ARVs to prevent her baby becoming infected is during labour. Depending on your particular circumstances it may be suggested that you take ARVs at other times as well. Deciding exactly which ARVs to take and when to take them can be quite difficult, because there is a need to balance a number of different things, including:

1. Your health as an HIV positive pregnant woman
2. Reducing the risk of HIV being passed to your baby
3. The possibility of developing ARV side effects
4. The possibility of drugs causing harm to your baby.

There may also be a difference between which drugs you would ideally take and which ones it is actually possible for you to take, as there is considerable variation worldwide in the cost of ARVs and their availability.

Should I breastfeed?

HIV is found in breast milk, and if you breastfeed there is a significant chance of passing HIV to your baby. So if you have access to safe breast milk substitutes (formula) then you are advised not to breastfeed.