School-based iron and folic acid supplementation for adolescent girls: findings from Manica Province, Mozambique

Abstract

Background: The 1997 Demographic and Health Survey in Mozambique shows that 47% of girls 15 to 19 years old living in Manica province (west-central Mozambique) are pregnant or have already had a child. A recent survey also shows that 45% of girls 10 to 18 years old attending school are anemic. Strategies are needed to build iron stores before pregnancy and to control seasonal and chronic iron deficiency and anemia in school-aged girls.

Objective: To assess the program effectiveness of two school-based weekly iron and folic acid (IFA) supplementation regimes (5-month supplementation vs. 8-month supplementation) in girls 10 to 18 years old attending school in Manica province.

Methods: Twelve schools were included in the study. Schools were ordered by descending mean hemoglobin concentration, and assigned alternately to study group 5 (six schools; 5-month supplementation) or study group 8 (six schools; 8-month supplementation). In both study groups, the weekly supplement contained 60 mg of elemental iron and 400 microg of folic acid. All girls received a single dose of mebendazol (500 mg) twice--once at the beginning of the study (T0) and once six months later (T6). Supplementation was implemented and supervised by the teachers of the schools included in the study. Between T0 and T3, girls in study group 8 received IFA supplements weekly whereas girls in study group 5 did not. Between T3 and T8, all girls in both groups received weekly IFA supplements.

Results: At T0, mean hemoglobin concentration and anemia prevalence were comparable in study groups 8 and 5 (125.3 +/- 12.6 g/L vs. 123.8 +/- 12.8 g/L; 28% vs. 29%, respectively). At T3, the mean hemoglobin concentration in study group 8 was significantly higher (126.3 +/- 14.3 g/L vs. 121.5 g/dL +/- 11.9 g/L, p < .001) and the prevalence of anemia was lower (28% vs. 35%, p = .076) than in study group 5. At T8, after an additional 5-month supplementation period in both study groups, mean hemoglobin concentration and anemia prevalence in study groups 8 and 5 were not significantly different (126.5 +/- 12.6 g/L vs. 124.9 +/- 12.3 g/L; 23% vs. 27%, respectively).

Conclusion: In Manica Province, school-based weekly IFA supplementation is a feasible and effective intervention to prevent seasonal drops in hemoglobin concentration and increases in anemia prevalence. Short supplementation periods can have an important impact on girls' hematological status. However, the size of girls' hematological response in this study was significantly lower that that observed in studies with similar population groups, initial anemia prevalence, supplement dosing, and/or supplementation regime.