Moving Closer to What Women Want?

A Review of Breastfeeding and Women Living With HIV in the UK and High-Income Countries

N Freeman-Romilly; F Nyatsanza; A Namiba; H Lyall


HIV Medicine. 2020;21(1):1-8. 

In This Article

Risk of HIV Transmission Through Breastfeeding

Breastfeeding, in HICs, by women living with HIV remains a contentious issue. There is a dichotomy of advice regarding infant feeding and HIV in the UK. The World Health Organization advocates that all new mothers should breastfeed regardless of their status,[13] while The British HIV Association (BHIVA) continues to recommend formula feeding by mothers living with HIV to eliminate the risk of postnatal transmission.[11]

Research conducted in low-income countries (LICs) in the 1990s showed that, without maternal or infant antiretroviral therapy (ART) or other interventions (such as elective caesarean), vertical transmission of HIV can occur in 15–25% of pregnancies during gestation or delivery, with an additional 4–20% of infants acquiring HIV during breastfeeding.[14,15]

At an individual level, the risk of HIV transmission through breastfeeding varies depending on maternal and infant factors. The risk of postnatal vertical transmission increases with reduced adherence to ART and the associated rise in levels of maternal HIV RNA in breastmilk.[16,17] However, maternal plasma viral load does not perfectly correlate with that of breastmilk, and breastmilk viral load is variable over time and between each breast.[16,18] There is evidence that postnatal vertical transmission can occur even when the mother has an undetectable plasma viral load.[3] Other factors that affect the risk of postnatal vertical infection are the duration of breastfeeding, presence of mastitis, and gastrointestinal health of the mother and infant.[13,19,18]

The studies noted in Table 1 were all conducted in resource-limited settings. There are no clinical trials on vertical HIV transmission risk through breastfeeding in resource-rich countries. The most recent data on breastfeeding from the Promoting Maternal and Infant Survival Everywhere (PROMISE) trial, a randomized clinical trial (RCT) of ART given to the mother versus pre-exposure prophylaxis given to the infant, where exclusive breastfeeding was advised to 6 months of age with subsequent introduction of complementary foods with on-going breastfeeding, as per WHO guidance, did not demonstrate any difference between arms.[10] The overall transmission rate at 1 year was 0.7% [95% confidence interval (CI) 0.3–1.4].[10]