HIV Prevention

Preventing Perinatal Transmission of HIV

Last Reviewed: July 26, 2023

Key Points

  • People should get tested for HIV before they become pregnant or as early as possible during each pregnancy and during the third trimester. The earlier HIV is detected, the sooner HIV medicines (also known as antiretrovirals) can be started.
  • Perinatal transmission of HIV is when HIV is passed from a person with HIV to their child during pregnancy, childbirth (also called labor and delivery), or breastfeeding (through breast milk). Perinatal transmission of HIV is also called mother-to-child transmission of HIV.
  • Pregnant people with HIV should take antiretroviral therapy (ART) throughout pregnancy and childbirth to prevent perinatal transmission of HIV. ART is the use of a combination of HIV medicines (antiretrovirals) to treat HIV. The use of HIV medicines and other strategies have helped lower the rate of perinatal transmission of HIV to 1% or less in the United States and Europe.
  • Most pregnant people with HIV can have vaginal deliveries.  If someone has a high viral load (more than 1,000 copies/mL) or an unknown viral load near the time of delivery, a scheduled cesarean delivery (sometimes called a C-section) can reduce the risk of perinatal transmission of HIV.
  • After birth, babies born to people with HIV should receive HIV medicines to reduce the risk of perinatal transmission. Several factors determine what HIV medicines babies receive and how long they receive the medicines.
  • Although HIV can be transmitted through breastfeeding, taking HIV medicines and having an undetectable viral load during pregnancy and throughout breastfeeding lower the risk of passing HIV to less than 1%. Pregnant people with HIV should talk to their health care provider about options for feeding their baby.

Is HIV testing recommended for pregnant people?

The Centers for Disease Control and Prevention (CDC) recommends that all people get tested for HIV before they become pregnant and as early as possible during each pregnancy and in the third trimester. The earlier HIV is detected, the sooner HIV medicines can be started.

All people who are pregnant or trying to get pregnant should encourage their partners also to get tested for HIV and, if possible, screened for other sexually transmitted infections (STIs). STIs can increase the amount of HIV in the body (viral load) in people with HIV. If any partner has HIV, that partner should take HIV medicine as prescribed to stay healthy and prevent transmission.

What is perinatal transmission of HIV?

Perinatal transmission of HIV is when HIV is passed from a person with HIV to their child during pregnancy, childbirth (also called labor and delivery), or breastfeeding (through breast milk). Perinatal transmission of HIV is also called mother-to-child transmission of HIV and vertical transmission of HIV.

The use of HIV medicines and other strategies have helped to lower the rate of perinatal transmission of HIV to 1% or less in the United States and Europe. (HIV medicines are called antiretrovirals.)

How do HIV medicines prevent perinatal transmission of HIV?

Antiretroviral therapy (ART) is the use of HIV medicines to treat HIV infection. Pregnant people with HIV should take HIV medicines to reduce the risk of perinatal transmission of HIV. The earlier HIV medicines are started, the more effective they are at preventing perinatal transmission of HIV. People with HIV who are trying to conceive should start HIV medicines before they become pregnant to prevent perinatal transmission. Pregnant and breastfeeding people with HIV should take HIV medicines throughout pregnancy, childbirth, and breastfeeding to prevent perinatal transmission. HIV medicines also protect the birthing parent’s health.

HIV medicines, when taken as prescribed, prevent HIV from multiplying and reduce viral load. An undetectable viral load is when the level of HIV in the blood is too low to be detected by a viral load test. The risk of perinatal transmission of HIV during pregnancy and childbirth is lowest when a person with HIV has an undetectable viral load. Having an undetectable viral load during pregnancy and throughout breastfeeding lowers the risk of perinatal transmission of HIV to less than 1%. Maintaining an undetectable viral load also helps keep the parent-to-be healthy.

After birth, babies born to people with HIV receive medicines to reduce the risk of transmission of HIV. Several factors determine what medicines babies receive and how long they receive the medicines.

Are HIV medicines safe to use during pregnancy?

HIV medicines are safe to use during pregnancy. HIV medicines do not increase the risk of birth defects. Health care providers discuss the benefits and risks of specific HIV medicines when helping people with HIV decide which medicines to use during pregnancy or while they are trying to conceive. If an individual gets pregnant while on HIV medication, they should stay on that medication unless instructed to change by their health care provider.

Are there other ways to prevent perinatal transmission of HIV?

In people who have a high HIV viral load (more than 1,000 copies/mL) or an unknown viral load near the time of delivery, a cesarean delivery (sometimes called a C-section) can reduce the risk of perinatal transmission.

Pregnant people with HIV are encouraged to talk to their medical team about options for feeding their baby after birth. With consistent use of HIV medicine and an undetectable viral load during pregnancy and throughout breastfeeding, the risk of transmission to a breastfed baby is low: less than 1%, but not zero. Alternatively, properly prepared formula and pasteurized donor human milk from a milk bank are options that eliminate the risk of transmission to a baby after birth. Pregnant people with HIV can speak with their health care provider to determine what method of feeding their baby is right for them.

Additionally, babies should not eat food that was pre-chewed by a person with HIV.

This fact sheet is based on information from the following sources:

From CDC:

From the Department of Health and Human Services:

Also see the HIV Source collection of HIV links and resources. For more information regarding infant feeding for people with HIV, see HIVE and the Well Project.