by Ann Ashworth.
The HIV virus can be passed from an HIV-infected mother to her baby. This is called mother-to-child transmission (MTCT). It can occur during pregnancy, labour and delivery, and through breast-feeding. Antiretroviral drugs such as Nevirapine reduce the risk of MTCT.
Risk through breast-feeding
The risk of passing the virus through breast-feeding depends on:
- breast-feeding duration The longer breast-feeding continues, the greater the risk of MTCT. The risk is thought to be about 5% in the first six months, 10% over the first 12 months, and 15–20% if the baby is breast-fed for 24 months.
- pattern of breast-feeding The risk is lower if the baby is fed only breast milk.
breast health The risk is higher if nipples are cracked or bleed, or if the breast is sore or inflamed (mastitis, breast abscess).
- timing of the mother’s HIV infection The risk of MCTC is higher if the mother becomes infected during pregnancy or while breast-feeding.
- mother’s immune status The risk is greater if the mother’s immunity is low, for example, due to malnutrition or because she is in the advanced stages of HIV disease.
Mothers with HIV have a difficult choice, especially if they live in poor conditions. Choosing not to breast-feed may prevent some infants becoming infected with HIV but can greatly increase the risk of death from other causes. UNICEF estimates that for every child dying from HIV through breast-feeding, many more die because they are not breast-fed.
It is important to discuss with HIV-positive mothers the feeding options available to them so they can make an informed choice. In most situations the options will be to breast-feed or to give replacement feeding (such as powdered milk). In some cities in Brazil, mothers with HIV may express their breast milk and have it made safe by heat treatment at a breast milk bank.
Babies benefit from the immune factors in breast milk and its high nutritional value. They are less likely to die from diarrhoea and pneumonia but they risk getting the HIV virus. This risk is small if the mother:
- breast-feeds exclusively – this means the mother and others in the house-hold must not give the baby water or other fluids or food
- maintains healthy breasts through good breast-feeding practices, such as breast-feeding on demand and having the baby correctly attached on the breast
- seeks help promptly for nipple or breast problems, and for thrush in the child’s mouth or on her nipples
- avoids becoming infected, or re-infected, with HIV while breast-feeding
- starts complementary feeding at six months (see pages 1–3 ) and stops breast-feeding as soon as is practical.
The risks of HIV through breast-feeding
One in every 20 babies will become infected if breast-fed for six months. Three in every 20 will become infected if breast-feeding continues for two years.
There is no risk of transmitting the virus but there is a risk of death by losing breast milk’s protective immunity and from unhygienic or incorrectly prepared feeds. This risk is high if a mother cannot afford sufficient milk, has an untreated water supply, poor sanitation, scarce fuel, no fridge, feeds by bottle or is poorly educated. In communities where breast-feeding is the usual practice, mothers who choose replacement feeding will ‘stand out’ and may be alienated. Mothers may find it difficult to give only replacement feeding. For example, they may want to breast-feed at night when it is inconvenient to prepare a feed. Mixing breast-feeding with other ways of feeding is more risky in transmitting the virus than exclusive breast-feeding.
Replacement feeding should only be chosen if it is acceptable, affordable, sustainable and safe. Mothers must be told the danger of mixing artificial and breast-feeding. Breast-feeding is the best choice for HIV-negative women and for women whose HIV status is unknown.
Professor Ann Ashworth is a nutritionist at the London School of Hygiene and Tropical Medicine with many years of experience in young child feeding. E-mail: firstname.lastname@example.org. Public Health Nutrition Unit, London School of Hygiene and Tropical Medicine, 49–51 Bedford Square, London, UK, WC1B 3DP