HIV can travel across the placenta (the tissue that provides blood and nutrients to the baby from its mother and takes its waste away) during pregnancy and infect an unborn baby. A newborn baby can also get HIV during childbirth when it is exposed to its mother’s blood or other HIV-containing bodily fluids. HIV may also be transmitted through breastfeeding.1,2 However, with advances in HIV care, specifically antiretroviral therapy (ART, medications used to treat HIV), the risk of a pregnant woman transmitting the virus to her baby can be extremely low.
Risk of HIV transmission during pregnancy
If an HIV-positive pregnant woman takes no steps to prevent HIV transmission, such as taking medications, there is about a 15-45 percent chance that she will pass the virus to her baby.3 However, with appropriate management, this number can become 5 percent or less across the world, and less than 1 percent in the United States.3,4 The rate is the lowest for women who are taking ART prior to pregnancy, and increases as time between the start of pregnancy and ART increases. This is why it is important to start ART as soon as possible when pregnant, or as soon as the virus is detected.
HIV testing in pregnancy
Current guidelines from the American College of Obstetricians and Gynecologists (ACOG) indicate that women be tested for HIV as a part of their initial prenatal work-up when they first find out they are pregnant. A second HIV test may be recommended later in pregnancy, during the third trimester.
If a woman’s HIV status is unknown at the time of delivery, a rapid HIV test may be ordered. Knowing HIV status can help lead to earlier treatment, which reduces the risk of transmission.5
HIV treatment during pregnancy
If a woman is found to have HIV or knows she already has HIV, it’s important for her to start or continue treatment for the virus. This includes taking ART every day, exactly how it is prescribed. A doctor or healthcare provider will help determine the best treatment regimen and can help manage side effects if they arise. It’s important to check-in regularly with a healthcare provider throughout pregnancy and while taking ART. These medications should be taken through pregnancy, childbirth, and beyond.2,4
The exact treatment regimen used for HIV-positive women during pregnancy may vary based on a variety of factors. Drug resistance testing will be performed to determine what medications might work the best in suppressing the virus. Other factors considered when creating a treatment plan include, but are not limited to: whether or not the woman has had treatment before, how far along in her pregnancy she is, the side effects of treatment, her ability to adhere to treatment (take her treatment exactly as prescribed), what her current viral load is, and what medications she has used in the past (if any).
A backbone treatment of two NRTI medications (nucleoside reverse transcriptase inhibitors), including tenofovir disoproxil fumarate and emtricitabine, tenofovir disoproxil fumarate and lamivudine, or abacavir and lamivudine is often used. Additional drugs that can be added onto this may depend on a variety of factors and include boosted protease inhibitors (such as atazanavir and ritonavir or darunavir and ritonavir) or integrase inhibitors (such as dolutegravir or raltegravir).
Everyone’s treatment regimen may vary and will be determined by a healthcare provider. Some HIV medications are not indicated for use during pregnancy, and a woman’s previously used ART regimen may need to be adjusted when she finds out she’s pregnant.6
Birth and beyond
Giving birth via a vaginal delivery is safe in many situations where the mother has HIV. However, if an HIV-positive pregnant woman has a high viral load (meaning she has a lot of active HIV in her body and is not well-controlled), she may need to have a cesarean delivery (C-section). A doctor or healthcare provider will determine the safest method of delivery in your situation.
HIV can be passed through breastmilk, so HIV-positive women are encouraged to avoid breastfeeding and use formula.2,4 Babies born to HIV-positive mothers will receive prophylactic, or preventative, treatment for HIV, and will be tested several times for the virus.