October 25, 2002
As to why vitamin A supplements may increase the risk of children acquiring the virus from their mothers, Fawzi noted that past studies have shown the same result. Previous research found that vitamin A may increase the replication of HIV in infected cells, while another study reported that people with low levels of vitamin A in their blood were less likely than others to transmit the virus via heterosexual sex.
Half of the 1,078 pregnant HIV-positive women in the study received vitamin A supplements, while the others were given multivitamins without vitamin A. The researchers followed the women and their children from when they were 20 weeks along in the pregnancy through breast-feeding. Women who took vitamin A supplements were 38 percent more likely to transmit HIV to their children than women who received multivitamins. Multivitamins appeared to offer no benefit in preventing mother-to-child HIV transmission, except in women with low levels of white blood cells -- an indication of advanced disease -- who were 60 percent less likely to infect their children while breast feeding than women with low levels of the cells who were not given multivitamins.
In addition, mothers given multivitamins who had relatively low hemoglobin and gave birth to low-weight babies -- both signs of poor maternal nutrition -- were also less likely to transmit the virus to their babies. Children born to multivitamin-treated women with relatively weak immune systems and poor nutrition also appeared more likely to survive past two years of age and, if infected, live longer with the virus. Fawzi explained that vitamins B, C and E may have reduced the risk of HIV transmission by boosting the immune system in both mothers and babies.
In an interview, Fawzi said that providing pregnant HIV- positive women with multivitamins throughout their pregnancy could potentially be a cost-effective means of keeping their children healthy. "Prices of vitamins would be driven to a low level if mass production is undertaken for all women at risk," Fawzi said.