Women's Health
FAQ502, June 2018

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Testing for Human Immunodeficiency Virus (HIV)

What is human immunodeficiency virus?

Human immunodeficiency virus (HIV) is the virus that causes acquired immunodeficiency syndrome (AIDS). Once HIV is in your body, it attacks the immune system. As the immune system weakens, it is less able to resist disease and infections. AIDS is diagnosed when a person with HIV develops diseases that the immune system normally would fight off, such as pneumonia, certain types of cancer, and harmful infections.

How do you get human immunodeficiency virus?

HIV is passed from one person to another through contact with an infected person’s body fluids, such as semen, vaginal fluid, or blood. This can happen during sex or by sharing needles used to inject illegal drugs. An HIV-positive woman who is pregnant can pass the virus to her fetus during labor. Women with HIV who breastfeed also can pass the virus to their babies.

Who should be tested for human immunodeficiency virus?

HIV testing is a routine part of health care. Women aged 13–64 years should be tested for HIV at least once in their lifetime. HIV testing also is recommended for women who are pregnant or who are thinking about getting pregnant.

Why should you get tested for human immunodeficiency virus?

Unless you are tested, you may not know you have HIV until you get sick. Knowing your HIV status is critical for your health and the health of others. Early diagnosis and treatment with anti-HIV drugs can help people with HIV stay healthy for a long time and can decrease the chance of passing the virus to others.

Why should pregnant women be tested for human immunodeficiency virus?

If you are pregnant and have HIV, the virus can be passed to your fetus. The good news is that treatment during pregnancy and treating the baby after birth can greatly reduce the chance of this happening. Treatment during pregnancy also can help you stay healthy.

When should pregnant women be tested for human immunodeficiency virus?

If you are pregnant, you will be given a routine test for HIV during your first prenatal visit. If you are at an increased risk of HIV infection, you should be retested in the third trimester of pregnancy. You are at increased risk if you have any of the following risk factors:

  • Have had a diagnosis of another sexually transmitted infection (STI) in the past year
  • Inject drugs or have a sex partner who injects drugs
  • Exchange sex for money or drugs
  • Have a new sex partner or more than one sex partner during this pregnancy
  • Have a sex partner who is HIV positive or at high risk of being HIV positive

Where can you get a test for human immunodeficiency virus?

You can get an HIV test from your obstetrician–gynecologist (ob-gyn) or other health care professional. You also can get an HIV test at special HIV clinics. You can find testing locations at https://gettested.cdc.gov/.

How does the screening test work?

The recommended HIV screening test looks for the presence of HIV antibodies and a specific HIV antigen called p24 in a sample of your blood. Antibodies are made by the immune system in response to HIV. An antigen is a part of the virus. The test can detect the p24 antigen about 3 weeks after you get HIV. It takes a few days to get the results of this test.

Can you get faster tests?

There also are “rapid” HIV screening tests. With a rapid HIV screening test, results are ready quickly, ideally within 1 hour. Your ob-gyn or other health care professional may offer rapid testing. Rapid tests also may be available at health clinics, local health department testing offices, hospitals, and community centers.

What is a home screening test?

Home HIV screening kits test either a sample of oral fluid or a sample of blood that you get by pricking your finger. It is important to only use the home tests that are approved by the U.S. Food and Drug Administration and to read the information that comes with the kit. You must perform the test correctly to get an accurate result. The test may not work until 3–6 months after you get HIV. Test results may be negative if you do the test before then.

Should you get tested more than once?

Retesting is recommended each year if you have done any of the following since your most recent HIV test:

  • Inject (shoot) illegal drugs
  • Have a sex partner who injects drugs or has HIV
  • Exchange sex for drugs or money
  • Have a male sex partner who has had sex with men
  • Have more than one sex partner

You can be tested for HIV again at any time, even if you do not have risk factors. If you are older than 64 years and you have risk factors for HIV, yearly retesting is recommended. It also is a good idea for you and your partner to be tested before starting a new sexual relationship.

Are positive test results ever wrong?

A “reactive” or positive screening test result does not necessarily mean you have HIV. No matter what kind of screening test you have, a confirming test must be done if you have a reactive or positive screening test result. Confirming test results take about 2 weeks. If the confirming test result is positive, you have HIV.

What should you do if the confirming test result is positive?

If your HIV test is confirmed and you have the virus, you can pass the virus to others if you have unprotected sex or share needles to inject drugs. A positive test result does not tell you whether you have AIDS or if you will get sick. If you have HIV, you should see a health care professional, even if you do not feel sick.

How is human immunodeficiency virus treated?

Many drug therapies can help people with HIV stay healthy for a long time. The earlier you start treatment, the better for your long-term health. Early treatment also reduces your risk of passing the virus to uninfected sex partners.

How can women avoid passing human immunodeficiency virus to their babies?

Women can take the following steps:

  • Take anti-HIV drugs during your pregnancy as prescribed.
  • Have a cesarean birth if lab tests show that your level of HIV is high.
  • Take anti-HIV drugs during labor and delivery as needed.
  • Give an anti-HIV drug to your baby after birth.
  • Do not breastfeed.

By following these guidelines, 99% of women with HIV will not pass HIV to their babies.

What if a pregnant woman was not tested for human immunodeficiency virus before labor?

If you were not tested for HIV during pregnancy, you should have a rapid HIV test when you go into labor. If this result is positive, you will need to have a confirming HIV test. While you are waiting for these results, you can receive anti-HIV drugs during labor, and the baby can be given anti-HIV drugs in the first few days after birth.

Who should know that you tested positive for human immunodeficiency virus?

Your health care professional will report your positive test results (but not your name) to your state health department. This is done to keep track of how many people in the United States have HIV. All of your sexual partners and needle-sharing partners should know your HIV status so they can be tested and begin treatment if they are HIV positive. You can tell your partners yourself, or you can have the health care department in your state do it. If you choose to have the health department tell your partners, your name will not be used when the partner is told. Many states have laws that require you to tell your sexual partners and needle-sharing partners that you are HIV positive. You can learn more about sharing your HIV status at https://www.hiv.gov/hiv-basics/hiv-testing/just-diagnosed-whats-next/talking-about-your-hiv-status.


Acquired Immunodeficiency Syndrome (AIDS): A group of signs and symptoms, usually of severe infections, in a person who has human immunodeficiency virus (HIV).

Antibodies: Proteins in the blood that the body makes in reaction to foreign substances, such as bacteria and viruses.

Antigen: A substance that can trigger an immune response and cause the body to make an antibody.

Cesarean Birth: Birth of a fetus from the uterus through an incision made in the woman’s abdomen.

Human Immunodeficiency Virus (HIV): A virus that attacks certain cells of the body’s immune system. If left untreated, HIV can cause acquired immunodeficiency syndrome (AIDS).

Immune System: The body’s natural defense system against viruses and bacteria that cause disease.

Screening Test: A test that looks for possible signs of disease in people who do not have signs or symptoms.

Sexually Transmitted Infection (STI): An infection that is spread by sexual contact. Infections include chlamydia, gonorrhea, human papillomavirus (HPV), herpes, syphilis, and human immunodeficiency virus (HIV, the cause of acquired immunodeficiency syndrome [AIDS]).

If you have further questions, contact your obstetrician–gynecologist.

FAQ502: This information was designed as an educational aid to patients and sets forth current information and opinions related to women’s health. It is not intended as a statement of the standard of care, nor does it comprise all proper treatments or methods of care. It is not a substitute for a treating clinician’s independent professional judgment. Please check for updates at www.acog.org to ensure accuracy.

Copyright June 2018 by the American College of Obstetricians and Gynecologists

American College of Obstetricians and Gynecologists
409 12th Street SW, Washington, DC  20024-2188
Mailing Address: PO Box 96920, Washington, DC 20024-9998