Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, Massachusetts 02115, USA
Transmission of HIV from mothers to children may occur through
the transplacental, intrapartum, or breastfeeding routes. Adequate
nutritional status may reduce vertical transmission by affecting
several maternal or fetal and child risk factors for transmission
including enhancing systemic immune function in the mother or
fetus/child; reducing the rate of clinical, immunological, or
virological progression in the mother; reducing viral load or
the risk of viral shedding in lower genital secretions or breast
milk; reducing the risks of low birth weight or prematurity;
or by maintaining the integrity of the fetus/child gastrointestinal
integrity. In prospective observational studies, low plasma
vitamin A levels were associated with higher risks of vertical
transmission. However, findings from randomized, controlled
trials suggest that supplements of vitamin A or other vitamins
are unlikely to have an effect on vertical transmission during
pregnancy or the intrapartum period. The effect of other nutrient
supplements, such as zinc and selenium, is unknown. Similarly,
whether nutrition supplements of mothers during the breastfeeding
period has an effect on transmission is unknown. The potential
benefits of direct supplementation of children born to HIV-infected
women on transmission of HIV, as well as on the risk and severity
of childhood infections and mortality, are also important to
examine.
