If a woman has HIV, it is possible for it to be passed on to her baby during pregnancy or delivery or through breastfeeding. For this reason, in the UK, all pregnant women have an HIV test as part of routine antenatal care. Once a woman and her healthcare team know that she has HIV, steps can be taken to prevent HIV being passed on to her baby.

HIV treatment is very effective at preventing mother-to-child transmission of HIV. If you are pregnant, your doctor will discuss your HIV treatment options with you. If you are thinking about becoming pregnant, it is important to start discussing this with your healthcare team as soon as possible, as they can give you advice on conception and care and treatment during your pregnancy.  

If you have an undetectable viral load (see Viral load) while you are pregnant and at the time of delivery, then the risk of you passing on HIV to your baby is very low, but it is very important that your health and viral load are monitored while you are pregnant, and that you and your baby receive the right treatment and care during your pregnancy and after you have given birth.

You may have more frequent CD4 cell counts (see CD4 cell counts), including one just before the baby is born, to help plan your baby’s delivery. You are also likely to have more frequent viral load tests during your pregnancy, especially if you are starting treatment for the first time, to help prevent passing on HIV to your baby.

In addition to your HIV monitoring and antenatal care, you should have a sexual health screen in both your first and your third trimester of pregnancy. This is because some sexually transmitted infections can increase the risk of mother-to-child transmission. You will also be tested for the hepatitis B virus at this screening.

In the UK, it is recommended that women with HIV do not breastfeed their babies. HIV is present in breast milk and HIV can be passed on from mother to child through breastfeeding. Feeding with formula milk is safe and there is practical and financial support available to help you do this. Talk to your doctor, midwife, or someone else in your healthcare team, about feeding your baby, especially if you have concerns or questions.

If you decide to breastfeed, the risk of passing on HIV to your baby is lower if your viral load has been undetectable at every test. You should talk to your healthcare team about your decision, have a viral load test every month while you are breastfeeding and your baby should be tested for HIV each month. Your healthcare team will talk to you about the safest way to breastfeed your baby. Breast feeding if you have a detectable viral load puts your baby at significant risk of HIV infection.

Your baby will have HIV tests the day after he or she is born, and at six and twelve weeks after birth. If these tests are negative, your baby is very likely to be HIV-negative. He or she will have a final HIV antibody test at 18 months to confirm his/her status.

With the right treatment and care during pregnancy, delivery and after the birth, the risk of passing HIV on to your baby is very low – under 1%.