RESUMO
OBJECTIVE: To evaluate the efficacy of a multiple micronutrient fortified beverage containing eleven nutrients at physiological levels in prevention of anaemia and improving iron and vitamin A status during pregnancy. DESIGN: A randomised double blind placebo controlled study. SETTING: Mpwapwa and Kongwa Districts in Dodoma Region of Tanzania. SUBJECTS: Five hundred and seventy nine pregnant women were screened for entry into the study and 439 women who met the study criteria were enrolled. INTERVENTIONS: Study participants received either a fortified (F) or non-fortified (NF) orange flavoured drinks identical in appearance, provided in two self administered servings per day for an eight week period. MAIN OUTCOME MEASURES: Comparison of haemoglobin (Hb), serum ferritin (SF) and serum retinol (SR) at baseline and follow up. RESULTS: After eight weeks of supplementation, the F group (n=129) had a significantly higher Hb increase of 0.86 g/dL compared to 0.45 g/dL in the NF group (n=130) p<0.0001. Gestational age at entry into the study, moderated the effect on Hb of the fortified drink. Women at earlier gestational age upon entry, had a higher rise in Hb than women of late gestational age (0.8 g/dL versus 0.04 g/dL rise respectively, p=0.038, n=188). The risk of being anaemic at the end of the study for those in the F group was reduced by 51% (RR=0.49, CI=0.28 to 0.85). Iron stores (by serum ferritin levels) increased by 3 microg/L in the F group (p=0.012) and a decrease of 2 microg/L in the NF group (p=0.115). The follow up ferritin concentration depended on initial ferritin level. Regardless of treatment group, serum retinol concentrations were significantly higher in mothers who had delivered. Mothers who had adequate levels at entry benefited more from the supplement than those with low levels (0.26 micromol/L versus no significant difference). CONCLUSIONS: The multiple micronutrient-fortified beverage given for eight weeks to pregnant women improved their haemoglobin, serum ferritin and retinol status. The risk for anaemia was also significantly reduced. The important predictors of Hb increase at follow up were the fortified beverage, baseline Hb, serum retinol, baseline ferritin and gestational age at entry into study. Anthropological research showed that the beverage was highly acceptable and well liked.