Being diagnosed with human immunodeficiency virus (HIV) has been described as feeling like falling off a cliff — life changes in an instant. For example, if you’ve planned to have children, you might wonder if that hope has been dashed or if HIV and pregnancy can coexist. They can — thanks to modern treatment, many people with HIV live an average life span and can continue to pursue their goals, including to become pregnant.

The World Health Organization (WHO) says that every year around the globe, about 1.3 million women and girls who are HIV-positive become pregnant. Current approaches to pregnancy care and HIV prevention have improved the health of pregnant people who are HIV-positive and lowered the risk of transmission (passing the disease to their babies).

This article will review the current risk of HIV transmission during pregnancy and current methods for preventing it.

Transmission Risk

HIV transmission is possible at four points related to childbearing: in the second trimester, in the third trimester, during labor and delivery, and when breastfeeding.

Generally, the more virus in the blood and the more advanced the disease, the more likely HIV will be transmitted during pregnancy. Other factors that increase the risk of vertical transmission (passing the virus from parent to child) are:

• Coinfection (the presence of infection with other viruses or bacteria)
• Prolonged membrane rupture (the time between the parent’s water breaking and the baby’s delivery)
• Genetic differences affecting how viruses infect cells and the way the immune system responds

In people who have HIV but are not being treated, the risk of transmission during pregnancy or labor and delivery is about 15 percent to 30 percent. This risk increases by up to 15 percent in people whose HIV is untreated and who breastfeed, according to the WHO.

However, the risk of HIV transmission can be as low as 1 percent or less when prevention strategies are used. Therefore, getting proper treatment for HIV and using preventive measures can make a big difference in whether the virus is passed on to the baby.

Preventing Transmission

A range of medical interventions and strategies can help prevent HIV infection at each pregnancy-related stage that has a high risk of vertical transmission.

Antiretroviral Therapy

The most important tool for preventing HIV transmission in pregnancy is antiretroviral treatment (ART, sometimes called HAART for “highly active ART”). This is true for people currently pregnant and those who plan to become pregnant. ART reduces the amount of virus in the blood and other body fluids, optimally to undetectable levels. “Undetectable” means that the instrument used to test a blood sample can’t find enough virus to give a number value.

For people with well-controlled HIV prior to pregnancy, guidelines recommend continuing that treatment while pregnant. If you’re on ART with a viral load (amount of virus in the body) above 200 and less than 1,000 copies per milliliter of blood, you should undergo testing for drug resistance. If it seems your body may be resistant to current medications, speak with your health care provider about changing your treatment regimen.

Figuring out which ART regimen to use can be overwhelming. Discuss available options with with an HIV specialist and OB-GYN prior to starting treatment. Making this choice early in pregnancy — or before getting pregnant — gives the medications enough time to work.

The goal of ART is to reach an undetectable level of virus — ideally, before becoming pregnant. In pregnant people whose HIV is undetectable, the risk of passing HIV to their fetus can drop to less than 1 percent, according to HIVInfo, an online resource from the U.S. Department of Health and Human Services.

Occasionally, people are not able to reach undetectable levels despite HIV treatment. In these uncommon cases, treatment with ART is still important because any decrease in viral load can be helpful in lowering the risk of transmission.

Testing and Coinfection

For pregnant people who are HIV-negative, the American College of Obstetricians and Gynecologists (ACOG) recommends HIV testing early in the first trimester (first three months of pregnancy). Testing should be repeated early in the third trimester (before 36 weeks) in people at high risk of HIV. This screening helps identify HIV in people who don’t know they have it during the antepartum (pre-labor and delivery) period.

If a pregnant person is HIV-positive, regular blood tests to check viral load and immune system function can help guide treatment. ACOG also recommends testing for other sexually transmitted infections (STIs), including gonorrhea, hepatitis B, chlamydia, and syphilis.

Coinfection with other viruses or bacteria increases the risk of transmission. Abstaining from sex, getting vaccinated, and using condoms are the most effective ways to prevent coinfection during pregnancy. Early treatment of coinfection is needed in pregnant HIV-positive people to lower the likelihood of transmission.

Delivery

Recommendations for preventing transmission during labor and delivery vary based on a person’s HIV treatment status. Current guidelines place people in one of four categories (ideally based on HIV testing at 36 weeks of pregnancy):

• HIV-positive people who are undetectable on ART with a viral load of less than 50 copies per milliliter
• HIV-positive people whose viral load is between 50 and 1,000 copies per milliliter
• HIV-positive people whose viral load is higher than 1,000 copies per milliliter
• HIV diagnosis at labor in people who either are not on ART or may not be taking it as recommended

The guidelines for preventing transmission during labor and delivery can vary based on these categories. One common guideline is to continue ART during labor, with the exception of people who are diagnosed at labor. Regardless of viral load at the time of labor, ART should be continued in those who took it during pregnancy.

Treatment with zidovudine (an antiretroviral drug that may help lower transmission risk) during delivery depends on viral load. Zidovudine is not required in people with a viral load of less than 50 copies per milliliter, but some health experts recommend it for people with a viral load between 50 and 1,000. Vaginal delivery is also recommended for both of these categories.

People with a viral load of more than 1,000 copies per milliliter should also continue their ART in labor, even if they have not been taking it as recommended during pregnancy. Zidovudine treatment during labor is strongly recommended. Ideally, cesarean delivery at 38 weeks will be planned.

People who are diagnosed in labor or whose water breaks with a viral load above 1,000 copies per milliliter should be treated with zidovudine. The type of delivery (vaginal versus cesarean) depends on the individual situation.

Newborn Care

Preventing transmission extends into the postpartum (after-delivery) period. Recommendations for newborn care depend on the baby’s risk level:

• Low risk — A baby born to a person who had 10 weeks of appropriate ART during pregnancy and had an undetectable viral load at 36 weeks, with no acute HIV infection during pregnancy
• Medium risk — A baby born to a person with a viral load of less than 50 copies per milliliter but does not meet low-risk criteria
• High risk — A baby born to a person who was diagnosed at delivery, had acute HIV infection during pregnancy, or had a viral load greater than 50 copies per milliliter at the time of delivery

These risk levels and prevention guidelines apply to full-term babies (born at or after 37 weeks.

• Low risk — Zidovudine treatment for two weeks
• Medium risk — Zidovudine treatment for four to six weeks
• High risk — HIV therapy with three-drug treatment from birth for two to six weeks; if less than six weeks, continued use of zidovudine alone to complete six weeks of therapy

Breastfeeding

In the past, health experts did not recommend that an HIV-positive person breastfeed. Now that ART is widely available, these recommendations have changed.

For a parent who has undetectable HIV on ART, breastfeeding is an option. That being said, the risk of transmission is still about 1 percent, not zero. Deciding whether to breastfeed in this scenario requires a discussion between a new parent and their doctor.

A parent who is not on ART or does not have undetectable virus levels should feed their baby with formula or banked, pasteurized donor human milk. Importantly, their care team should ensure access to clean water, safe formula, and donor breast milk (if available).

If you have HIV and are pregnant or trying to become pregnant, the first step is to talk with a trusted HIV specialist and OB-GYN about treatment and preventing transmission to your baby. Together, you can come up with a plan that will allow you pursue your goals, including having children, while living with HIV.

Find Your Team

On myHIVteam, the social network for people with HIV and their loved ones, more than 37,000 members come together to ask questions, give advice, and share their stories with others who understand life with HIV.

Are you living with HIV and thinking of becoming pregnant? Have you discussed your plans with your health care provider? Share your tips and experiences in a comment below or on your Activities page.