Effect of multivitamin and vitamin A supplements on weight gain during pregnancy among HIV-1-infected women1–3

Background: The pattern of weight gain during pregnancy among HIV-infected women is largely unknown. Multivitamin supplementation was shown to be effective in preventing adverse pregnancy outcomes among HIV-positive women. These protective effects could be mediated in part by an improvement in the pattern of gestational weight gain. Objective: We examined the effects of multivitamin and vitamin A supplements on weight gain during the second and third trimesters of pregnancy among HIV-infected women. Design: We enrolled 1075 pregnant, HIV-1-positive women from Dar es Salaam, Tanzania, in a randomized, placebo-controlled trial. Using a 2-by-2 factorial design, we assigned each woman to 1 of 4 regimens: multivitamins (thiamine, riboflavin, niacin, folic acid, and vitamins B-6, B-12, C, and E), vitamin A, multivitamins including vitamin A, or placebo. The women took these oral supplements daily and were weighed monthly until the end of pregnancy. Results: The mean rate of weight gain was 306 g/wk during the second trimester and 247 g/wk during the third trimester. During the third trimester, average weight gain was significantly greater (by 304 g; 95% CI: 17, 590; P = 0.04) and the risk of low rate of weight gain (≤ 100 g/wk) was significantly lower (relative risk: 0.73; 95% CI: 0.58, 0.93) in women who received multivitamins than in women who did not. Multivitamins including vitamin A were protective against low weight gain during the second trimester compared with multivitamins alone. Conclusion: Multivitamin supplementation during pregnancy improves the pattern of weight gain among HIV-infected women. Am J Clin Nutr 2002;76:1082–90.