How much Antenatal Supplemental Iron is Required to Preserve Maternal Iron Status? The MINIMat Intervention trial in Bangladesh
Shirin Ziaei *
International Maternal and Child Health Unit (IMCH), Department of Women's and Children's Health, University Hospital, Uppsala, Sweden.
Anisur Rahman
International Centre for Diarrhoeal Disease Research(ICDDR), Dhaka, Bangladesh.
Shams El Arifeen
International Centre for Diarrhoeal Disease Research(ICDDR), Dhaka, Bangladesh.
Eva-Charlotte Ekström
International Maternal and Child Health Unit (IMCH), Department of Women's and Children's Health, University Hospital, Uppsala, Sweden.
*Author to whom correspondence should be addressed.
Abstract
Objectives: To prevent iron deficiency in pregnancy universal iron folic acid supplementation is recommended by WHO. We aimed to compare the effect of multiple micronutrients supplements with two different dosages of iron/folic acid supplements on maternal iron status.
Methods: In the MINIMat intervention trial in Bangladesh, pregnant women were randomized into three micronutrient supplementation groups: 30 mg iron/400 ugfolic acid (Fe30 F), 60 mg iron/400 ugfolic acid (Fe 60 F) and multiple micronutrients +30 mg iron/400 ugfolic acid (MM). Adherence was electronically monitored by use of eDEM-pillbottles. Plasma-ferritin (p-Ft) was assessed at start of supplementation (week 14) and at week 30 at gestation in random subset. Intent to treat and multivariate regression analyses were performed (n=561).
Results: Iron deficiency (ID) was 7% at start of supplementation. At wk 30 ID was 29% and mean p-Ft 20.0 ug/L with no differences according to supplementation type. Within each type there was a significant dose-effect per capsule on p-Ft that did not differ between types when amount of iron in the supplements was taken into consideration. There was no further dose-effect on p-Ft of iron intake exceeding 4 g. Using lowest tertile of iron intake as reference, middle and highest intake tertile increased p-Ft and showed a protective effect on ID at wk30 but did not differ between each other.
Conclusions: Despite no further effect on p-Ft of higher iron intake than 4 g, ID developed to become prevalent at wk 30 suggesting that iron intake exceeding 4 g contributes to limited extent to reduce ID in pregnancy. Supplement with multiple micronutrients did not provide any additional effect.