Iron deficiency in pregnancy and perinatal outcome

Abstract

Background: Iron deficiency (ID) is highly prevalent in pregnant women worldwide. While iron deficiency anemia (IDA) has been associated with preterm birth (PTB) and low birth weight (LBW), there is uncertainty about the possible effects of non-anemic ID on birth outcomes. Aim: The objective of this thesis was to investigate whether ID in pregnancy is an independent factor in contributing to LBW and PTB. Methods: A systematic search of the databases PubMed and Embase identified relevant articles published in the last ten years. Studies were considered eligible for inclusion if they addressed ID in pregnant women, using serum ferritin (SR) or soluble transferrin receptor (sTfR) as biomarkers, and possible associations with LBW or PTB. Studies were excluded if they were carried out in malaria endemic areas, included women with HIV or examined the effect of iron supplementation in pregnancy. Articles written in other languages than English were excluded. Titles and abstracts were screened for eligibility, and the articles considered relevant were read full text. Results: Of 694 individual articles identified from the database search, 15 were read full text and seven were included in the review. All included articles were observational studies. The results were inconsistent. Only one study reported significant correlation between first trimester maternal ID and lower birth weight. First trimester ID correlated with a higher risk of an LGA infant in another study. A third trimester study found that maternal ID was associated with a decreased risk of LWB and PTB. Conclusion: This literature has not found strong evidence of an isolated effect of maternal ID on LBW or PTB, but the possibility of effects cannot be dismissed based on the current evidence. The observational studies included have important differences in populations and study design, making comparisons problematic.