Randomised trial of effects of vitamin supplements on pregnancy outcomes and T cell counts in HIV-1-infected women in Tanzania

Background In HIV-1-infected women, poor micronutrient status has been associated with faster progression of HIV-1 disease and adverse birth outcomes. We assessed the effects of vitamin A and multivitamins on birth outcomes in such women. Methods In Tanzania, 1075 HIV-1-infected pregnant women at between 12 and 27 weeksʹ gestation received placebo (n=267), vitamin A (n=269), multivitamins excluding vitamin A (n=269), or multivitamins including vitamin A (n=270) in a randomised, double-blind, placebo-controlled trial with a 2×2 factorial design. We measured the effects of multivitamins and vitamin A on birth outcomes and counts of T lymphocyte subsets. We did analyses by intention to treat. Results 30 fetal deaths occurred among women assigned multivitamins compared with 49 among those not on multivitamins (relative risk 0•61 [95% CI 0•39–0•94] p=0•02). Multivitamin supplementation decreased the risk of low birthweight (<2500 g) by 44% (0•56 [0•38–0•82] p=0•003), severe preterm birth (<34 weeks of gestation) by 39% (0•61 [0•38–0•96] p=0•03), and small size for gestational age at birth by 43% (0•57 [0•39–0•82] p=0•002). Vitamin A supplementation had no significant effect on these variables. Multivitamins, but not vitamin A, resulted in a significant increase in CD4, CD8, and CD3 counts. Interpretation Multivitamin supplementation is a low-cost way of substantially decreasing adverse pregnancy outcomes and increasing T-cell counts in HIV-1-infected women. The clinical relevance of our findings for vertical transmission and clinical progression of HIV-1 disease is yet to be ascertained.