HIV Prevention

Preventing Perinatal Transmission of HIV

Last Reviewed: January 31, 2023

This fact sheet is being revised to align with the recent updates to the Infant Feeding section of the Perinatal Guidelines.

Key Points

  • Perinatal transmission of HIV is when HIV is passed from a woman with HIV to her 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.
  • Women should get tested for HIV before they become pregnant or as early as possible during each pregnancy. The earlier HIV is detected, the sooner HIV medicines can be started.
  • 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. (HIV medicines are called antiretrovirals.)
  • Pregnant women with HIV should take HIV medicines throughout pregnancy and childbirth to prevent perinatal transmission of HIV. A scheduled cesarean delivery (sometimes called a C-section) can reduce the risk of perinatal transmission of HIV in women who have a high viral load (more than 1,000 copies/mL) or an unknown viral load near the time of delivery.
  • After birth, babies born to women with HIV should receive HIV medicines to reduce the risk of perinatal transmission of HIV. Several factors determine what HIV medicines babies receive and how long they receive the medicines.
  • 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 medication 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.

What is perinatal transmission of HIV?

Perinatal transmission of HIV is when HIV is passed from a woman with HIV to her 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.

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.)

Is HIV testing recommended for pregnant women?

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

All women 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 diseases (STDs). STDs can increase viral loads in people with HIV. If any partner has HIV, that partner should take HIV medicine as prescribed to stay healthy and prevent transmission.

How do HIV medicines prevent perinatal transmission of HIV?

Pregnant women with HIV should take HIV medicines to reduce the risk of perinatal transmission of HIV. When started early, HIV medicines can be more effective at preventing perinatal transmission of HIV. Women with HIV who are trying to conceive should start HIV medicines before they become pregnant to prevent perinatal transmission of HIV. Pregnant women with HIV should take HIV medicines throughout pregnancy and childbirth to prevent perinatal transmission of HIV. HIV medicines also protect the woman’s health.

HIV medicines, when taken as prescribed, prevent HIV from multiplying and reduce the amount of HIV in the body (called the 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 woman with HIV has an undetectable viral load. Maintaining an undetectable viral load also helps keep the mother-to-be healthy.

Some HIV medicines used during pregnancy that pass from the pregnant woman to her unborn baby through cesarean delivery  (sometimes called a C-section) can reduce the risk of perinatal transmission of HIV in women who have a high viral load (more than 1,000 copies/mL) or an unknown viral load near the time of delivery.

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

Are HIV medicines safe to use during pregnancy?

Most HIV medicines are safe to use during pregnancy. In general, HIV medicines do not increase the risk of birth defects. Health care providers discuss the benefits and risks of specific HIV medicines when helping women with HIV to decide which HIV medicines to use during pregnancy or while they are trying to conceive.

Are there other ways to prevent perinatal transmission of HIV?

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 medication 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 the Department of Health and Human Services:

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