HIV Prevention

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.

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.)

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.

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.

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.

Read the following HIVinfo fact sheets:

• HIV Medicines During Pregnancy and Childbirth
• Preventing Perinatal Transmission of HIV After Birth

From CDC:

• HIV and Perinatal Transmission

From the Department of Health and Human Services:

• Recommendations for the Use of Antiretroviral Drugs During Pregnancy and Interventions to Reduce Perinatal HIV Transmission in the United States: 
  • Introduction
  • General Principles Regarding Use of Antiretroviral Drugs During Pregnancy: Overview and Teratogenicity
  • Infant Feeding for Individuals with HIV in the United States
  • Management of Infants Born to People with HIV Infection: Antiretroviral Management of Newborns with Perinatal HIV Exposure or HIV Infection

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.

The person-to-person spread of HIV is called HIV transmission. People can get or transmit HIV only through specific activities, such as sex or injection drug use. HIV can be transmitted only in certain body fluids from a person who has HIV:

• Blood
• Semen
• Pre-seminal fluids
• Rectal fluids
• Vaginal fluids
• Breast milk

HIV transmission is only possible if these fluids come in contact with a mucous membrane or damaged tissue or are directly injected into the bloodstream (from a needle or syringe). Mucous membranes are found inside the rectum, the vagina, the opening of the penis, and the mouth.

In the United States, HIV is spread mainly by:

• Having anal or vaginal sex with someone who has HIV without using a condom or taking medicines to prevent or treat HIV
• Sharing injection drug equipment (works), such as needles, with someone who has HIV

HIV can also spread from a woman with HIV to her child during pregnancy, childbirth (also called labor and delivery), or breastfeeding. This is called perinatal transmission of HIV. Perinatal transmission of HIV is also called mother-to-child transmission of HIV.

You cannot get HIV from casual contact with a person who has HIV, such as a handshake, a hug, or a closed-mouth kiss. And you cannot get HIV from contact with objects, such as toilet seats, doorknobs, or dishes used by a person who has HIV.

Use the You Can Safely Share…With Someone With HIV infographic from HIVinfo to spread this message.

Anyone can get HIV, but you can take steps to protect yourself from HIV.

• Get tested for HIV. Talk to your partner about HIV testing and get tested before you have sex. Use the GetTested locator from the Centers for Disease Control and Prevention (CDC) to find an HIV testing location near you.
• Choose less risky sexual behaviors. HIV is mainly spread by having anal or vaginal sex without a condom or without taking medicines to prevent or treat HIV.
• Use condoms every time you have sex. Read this fact sheet from CDC on how to use condoms correctly.
• Limit your number of sexual partners. The more partners you have, the more likely you are to have a partner with poorly controlled HIV or to have a partner with a sexually transmitted disease (STD). Both of these factors can increase the risk of HIV.
• Get tested and treated for STDs. Insist that your partners get tested and treated, too. Having an STD can increase your risk of getting HIV or spreading it to others.
• Talk to your health care provider about pre-exposure prophylaxis (PrEP). PrEP is an HIV prevention option for people who do not have HIV but who are at risk of getting HIV. PrEP involves taking a specific HIV medicine every day to reduce the risk of getting HIV through sex or injection drug use. For more information, read the HIVinfo fact sheet on Pre-Exposure Prophylaxis (PrEP).
• Do not inject drugs. But if you do, use only sterile drug injection equipment and water, and never share your equipment with others.

Take HIV medicines daily. Treatment with HIV medicines (called antiretroviral therapy or ART) helps people with HIV live longer, healthier lives. ART cannot cure HIV, but it can reduce the amount of HIV in the body (called the viral load). One of the main goals of ART is to reduce a person's viral load to an undetectable level. An undetectable viral load means that the level of HIV in the blood is too low to be detected by a viral load test. People with HIV who maintain an undetectable viral load have effectively no risk of transmitting HIV to an HIV-negative partner through sex.

Here are some other steps you can take to prevent HIV transmission:

• Use condoms correctly every time you have sex.
• Talk to your partner about taking PrEP.
• If you inject drugs, do not share your needles, syringes, or other drug equipment with your partner.

Yes, HIV medicines are also used for post-exposure prophylaxis (PEP) and to prevent perinatal transmission of HIV.

• Post-exposure prophylaxis (PEP)
  PEP means taking HIV medicines within 72 hours after a possible exposure to HIV to prevent HIV infection. PEP should be used only in emergency situations. It is not meant for regular use by people who may be exposed to HIV frequently. For more information, read the HIVinfo fact sheet on Post-Exposure Prophylaxis (PEP).
• Prevention of perinatal transmission of HIV
  Pregnant women with HIV take HIV medicines for their own health and to prevent perinatal transmission of HIV. After birth, babies born to women with HIV receive HIV medicine to protect them from infection with any HIV that may have passed from mother to child during childbirth. For more information, read the HIVinfo fact sheet on Preventing Perinatal Transmission of HIV.

From CDC:

• HIV Transmission
• HIV Prevention
• PrEP (Pre-Exposure Prophylaxis)
• PEP (Post-Exposure Prophylaxis)

From the Department of Health and Human Services:

• Recommendations for the Use of Antiretroviral Drugs in Pregnant Women with HIV Infection and Interventions to Reduce Perinatal HIV Transmission in the United States:
  • General Principles Regarding Use of Antiretroviral Drugs During Pregnancy: Overview 
  • o Management of Infants Born to Women with HIV Infection: Antiretroviral Management of Newborns with Perinatal HIV Exposure or HIV Infection

Also see the HIV Source collection of HIV links and resources.

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.

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.)

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.

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.

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.

Read the following HIVinfo fact sheets:

• HIV Medicines During Pregnancy and Childbirth
• Preventing Perinatal Transmission of HIV After Birth

From CDC:

• HIV and Perinatal Transmission

From the Department of Health and Human Services:

• Recommendations for the Use of Antiretroviral Drugs During Pregnancy and Interventions to Reduce Perinatal HIV Transmission in the United States: 
  • Introduction
  • General Principles Regarding Use of Antiretroviral Drugs During Pregnancy: Overview and Teratogenicity
  • Infant Feeding for Individuals with HIV in the United States
  • Management of Infants Born to People with HIV Infection: Antiretroviral Management of Newborns with Perinatal HIV Exposure or HIV Infection

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.

PrEP stands for pre-exposure prophylaxis. The word “prophylaxis” means to prevent or control the spread of an infection or disease.

PrEP is when people who do not have HIV but are at risk of getting HIV take HIV medicine every day to prevent HIV infection. PrEP is used by people without HIV who are at risk of being exposed to HIV through sex or injection drug use. Two HIV medicines are approved by the U.S. Food and Drug Administration (FDA) for use as PrEP: Truvada and Descovy. Which medicine to use for PrEP depends on a person’s individual situation.

If a person is exposed to HIV through sex or injection drug use, having the PrEP medicine in the bloodstream can stop HIV from taking hold and spreading throughout the body. However, if PrEP is not taken every day, there may not be enough medicine in the bloodstream to block the virus.

PrEP is for people who do not have HIV but are at risk of getting HIV through sex or injection drug use.

Specifically, the Centers for Disease Control and Prevention (CDC) recommends that PrEP be considered for people who are HIV negative and who have had anal or vaginal sex in the past 6 months and:

• have a sexual partner with HIV (especially if the partner has an unknown or detectable viral load), or
• have not consistently used a condom, or
• have been diagnosed with a sexually transmitted disease (STD) in the past 6 months.

PrEP is also recommended for people without HIV who inject drugs and:

• have an injection partner with HIV, or
• share needles, syringes, or other equipment to inject drugs.

PrEP should also be considered for people without HIV who have been prescribed non-occupational post-exposure prophylaxis (nPEP) and:

• report continued risk behavior, or
• have used multiple courses of PEP.

If you think PrEP may be right for you, talk to your health care provider.

PrEP is most effective when taken consistently each day. CDC reports that studies on PrEP effectiveness have shown that consistent use of PrEP reduces the risk of getting HIV from sex by about 99% and from injection drug use by at least 74%. Adding other prevention methods, such as condom use, along with PrEP can further reduce a person’s risk of getting HIV.

In some people, PrEP can cause side effects, such as nausea. These side effects are not serious and generally go away over time. If you are taking PrEP, tell your health care provider if you have any side effect that bothers you or that does not go away.

If you think PrEP may be right for you, see a health care provider. PrEP can be prescribed only by a health care provider. If your health care provider agrees that PrEP may reduce your risk of getting HIV, the next step is an HIV test. You must be HIV negative to start PrEP.

Once you start PrEP, you will need to take PrEP every day. PrEP is much less effective when it is not taken every day.

Continue to use condoms while taking PrEP. Even though daily PrEP can greatly reduce your risk of HIV, it does not protect against other STDs, such as gonorrhea and chlamydia. Combining condom use with PrEP will further reduce your risk of HIV, as well as protect you from other STDs.

You must also take an HIV test every 3 months while taking PrEP, so you will have regular follow-up visits with your health care provider. If you are having trouble taking PrEP every day or if you want to stop taking PrEP, talk to your health care provider.

From CDC:

• Pre-Exposure Prophylaxis (PrEP)
• PrEP Effectiveness
• HIV Basics: PrEP (Pre-Exposure Prophylaxis)
• PrEP Resources

Also see the HIV Source collection of HIV links and resources.

PEP stands for post-exposure prophylaxis. The word “prophylaxis” means to prevent or control the spread of an infection or disease. PEP means taking HIV medicines within 72 hours (3 days) after a possible exposure to HIV to prevent HIV infection.

PEP should be used only in emergency situations. It is not meant for regular use by people who may be exposed to HIV frequently. PEP is not intended to replace regular use of other HIV prevention methods, such as consistent use of condoms during sex or pre-exposure prophylaxis (PrEP). PrEP is different than PEP, in that people at risk for HIV take a specific HIV medicine daily to prevent getting HIV.

For more information, see the HIVinfo fact sheets on The Basics of HIV Prevention and Pre-Exposure Prophylaxis (PrEP).

PEP may be prescribed for people who are HIV negative or do not know their HIV status, and who in the last 72 hours:

• May have been exposed to HIV during sex
• Shared needles or other equipment (works) to inject drugs
• Were sexually assaulted
• May have been exposed to HIV at work

If you think you were recently exposed to HIV, talk to your health care provider or an emergency room doctor about PEP right away.

A health care worker who has a possible exposure to HIV should seek medical attention immediately.

PEP must be started within 72 hours (3 days) after a possible exposure to HIV. The sooner PEP is started after a possible HIV exposure, the better. According to research, PEP will most likely not prevent HIV infection if it is started more than 72 hours after a person is exposed to HIV.

If you are prescribed PEP, you will need to take the HIV medicines every day for 28 days.

The Centers for Disease Control and Prevention (CDC) provides guidelines on recommended HIV medicines for PEP. The CDC guidelines include recommendations for specific groups of people, including adults and adolescents, children, pregnant women, and people with kidney problems. The most recent PEP recommendations can be found on CDC’s PEP resources webpage.

Your health care provider or emergency room doctor will work with you to determine which medicines to take for PEP.

PEP is effective in preventing HIV infection when it is taken correctly, but it is not 100% effective. The sooner PEP is started after a possible HIV exposure, the better. Every hour counts. While taking PEP, it is important to keep using other HIV prevention methods, such as using condoms with sex partners and using only new, sterile needles when injecting drugs.

The HIV medicines used for PEP may cause side effects in some people. The side effects can be treated and are not life-threatening. If you are taking PEP, talk to your health care provider if you have any side effect that bothers you or that does not go away.

From CDC:

• About PEP
• HIV Basics: PEP
• PEP Resources
• PEP and Workplace Exposures

Also see the HIV Source collection of HIV links and resources.