Effect of different doses of iron supplementation during pregnancy on maternal and infant health
Currently, there is no consensus regarding the optimum iron supplementation during pregnancy. The aim of this study is to evaluate the effect of different iron supplementation doses (including no supplementation) during pregnancy on the iron status of the mother and on the health of the neonate. A longitudinal study was conducted involving 358 pregnant women and their newborns. Mothers were classified as non-supplemented, low iron supplemented (<60 mg/day), moderate iron supplemented (between 60 and 100 mg/day) or high iron supplemented (>100 mg/day). General clinical and obstetric histories, haemoglobin (Hb), serum ferritin (SF) and transferrin saturation were evaluated in the first, second, third trimesters, and at partum. SF and Hb decreased less sharply in the iron-supplemented groups compared to the non-supplemented group. The higher the doses of iron supplementation, the lower the percentages of iron depletion at partum (p < 0.001), iron deficiency anaemia (p < 0.001) and preterm deliveries (p = 0.009) as well as a higher birth weight of the newborn. However, the group with high supplementation had a greater percentage (27.6 %) of women at risk of haemoconcentration at partum. Our Mediterranean women began gestation with iron stores close to deficit (SF, 28.1 μg/L; 95 % CI 27.9–28.4). With these iron stores, supplementation with iron at daily doses of between 60 and 100 mg appears to be the most beneficial for the health of mother and child. These findings need to be confirmed in further randomised clinical trials.
KeywordsDietary supplements Iron Premature birth Pregnancy Iron deficiency anaemia Haemoconcentration
This study was financially supported by a grant (PI052462) from the Health Research Fund of the Ministry of Health and Consumption (Madrid, Spain) [Instituto de Salud Carlos III, Fondo de Investigación Sanitaria, Ministerio de Sanidad y Consumo]. The authors would like to thank all the participating pregnant women for their enthusiastic collaboration. We thank the Clinical Chemistry Laboratories of the Hospital Sant Joan de Reus (Catalunya, Spain) for help with the blood analyses. We thank Fernando Viteri, iron expert, professor emeritus at the University of California, Berkeley, and research scientist at the Children’s Hospital Oakland Research Institute, for his expert assistance with the study and Ginny Gildengorin for the discussion of the analysis.
Conflict of interest
The authors declare that they have no conflict of interest.
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