Mothers with well-controlled HIV have a low likelihood of transmitting the virus to their infants through breastfeeding, and revised U.S. guidelines state that HIV-positive people should receive patient-centered counseling to support shared decision-making about infant feeding. The same considerations apply to transgender men and nonbinary people who wish to chestfeed.

The new thinking about infant feeding was the topic of a special session at the 30th Conference on Retroviruses and Opportunistic Infections (CROI) last month in Seattle. In this video, which you can watch at the top of this article, Laura Cheever, MD, the Health Resources and Services Administration’s associate administrator for the HIV/AIDS Bureau and head of the Ryan White HIV/AIDS Program, discusses the CROI presentation and the new recommendations. (Cheever also discusses another study showing that long-acting injectable treatment may be feasible for some people without viral suppression.)

Traditionally, women with HIV in the United States have been advised not to breastfeed because of the risk of mother-to-child transmission. However, in low-income countries where people do not have reliable access to clean water and safe formula, the risk/benefit equation favors breastfeeding.

But things have changed in the era of U=U (Undetectable Equals Untransmittable). Studies have definitively shown that people who take antiretroviral therapy consistently and maintain an undetectable viral load do not transmit HIV via sex. There is less evidence about whether U=U also applies to breastfeeding.

The threshold for sexual transmission of HIV is usually given as a viral load below 200 copies for at least six months. The viral load threshold for reducing perinatal HIV transmission during gestation or delivery is thought to be 50 copies. The lower limit for transmission via breastfeeding is unknown. There are a couple of known cases of transmission from breastfeeding mothers with a viral load below 50, but this is rare, occurring less than 1% of the time. For example, findings from the DolPHIN-2 trial, presented at CROI 2021, found that among 242 infants born to HIV-positive women in Uganda and South Africa who were on antiretroviral therapy and exclusively breastfed for six months, only one baby acquired the virus.

Women living with HIV in the United States and other high-income countries have advocated for more autonomy in decisions about infant feeding. While breastfeeding comes with a small risk of transmission, it also offers many benefits, including better infant nutrition, improved health, lower cost, cultural acceptability, reduced stigma and mother-child bonding. (The Well Project has summarized the discussion and supporting evidence.) In 2020, experts in the United States and Canada issued a consensus statement affirming the need for parents living with HIV “to have access to the information, support and tools necessary to make informed infant-feeding decisions.” 

In January 2023, the Department of Health and Human Services (HHS) revised its Recommendations for the Use of Antiretroviral Drugs During Pregnancy and Interventions to Reduce Perinatal HIV Transmission in the United States to say that people with HIV should “receive evidence-based, patient-centered counseling to support shared decision-making about infant feeding.” This counseling should begin prior to conception or as early as possible in pregnancy and continue during pregnancy and after delivery.

The guidelines state that feeding properly prepared formula or donor human milk from a milk bank eliminates the risk of HIV transmission to the infant. Achieving and maintaining viral suppression during pregnancy and postpartum “decreases breastfeeding transmission risk to less than 1%, but not zero.” Replacement feeding with formula or donor milk is recommended for people who are not on treatment or have not maintained viral suppression for at least the third trimester and during delivery.

“Individuals with HIV who are on [antiretroviral therapy] with a sustained undetectable viral load and who choose to breastfeed should be supported in this decision,” the guidelines continue. “Individuals with HIV who choose to formula feed should be supported in this decision. Providers should ask about potential barriers to formula feeding and explore ways to address them.” Importantly, the guidelines emphasize that engaging child protective services or similar agencies “is not an appropriate response to the infant feeding choices of an individual with HIV.”


In this video, Harold Phillips, director of the White House Office of National AIDS Policy, discusses the new guidance with Commander Michelle Sandoval-Rosario, DrPH, MPH, of the HHS Office of the Assistant Secretary for Health.


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