title: Reduced risk for placental malaria in iron deficient women.
abstract: BACKGROUND
  Nutritional iron deficiency may limit iron availability to the malaria parasite reducing infection risk, and/or impair host immunity thereby increasing this risk. In pregnant women, there is evidence of an adverse effect with iron supplementation, but the few reported studies are strongly confounded.
  
  
  METHODS
  A case control study in pregnant Malawian women was undertaken in Chikhwawa southern Malawi in order to describe iron status in relation to placental malaria controlling for several confounding factors. Pregnancy characteristics were obtained and a blood sample at delivery. A full blood count was performed and serum ferritin and transferrin receptor quantified by enzyme-linked immunoassay. DNA analysis was used to identify genetic polymorphisms for ABO phenotype, hemoglobin HbS, and glucose -6 phosphate dehydrogenase deficiency. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection.
  
  
  RESULTS
  112 cases with placental malaria were identified and 110 women with no evidence of placental infection. Iron deficiency was less frequent in women with placental Plasmodium falciparum infection. In those with acute, chronic or past placental infections the odds ratio for iron deficiency was 0.4, 95% CI 0.2-0.8, p = 0.01; for acute and chronic infections 0.4, 0.2-0.8, p = 0.006; for acute infection 0.3, 0.1-0.7, p = 0.001. The association was greater in multigravidae.
  
  
  CONCLUSIONS
  Women with either acute, or acute and chronic placental malaria were less likely to have iron deficiency than women without placental malaria infection There is a priority to establish if reversing iron deficiency through iron supplementation programs either prior to or during pregnancy enhances malaria risk.
authors.affiliation: University of Malawi College of Medicine, Biochemistry Department, Blantyre, Malawi.
authors.forename: Edward L
authors.initials: EL
authors.lastname: Senga
authors.forename: Gregory
authors.initials: G
authors.lastname: Harper
authors.forename: Gibby
authors.initials: G
authors.lastname: Koshy
authors.forename: Peter N
authors.initials: PN
authors.lastname: Kazembe
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Brabin
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics; D001772:Blood Cell Count; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005293:Ferritins / Q000097:blood; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics; D006451:Hemoglobin, Sickle / Q000235:genetics; D006801:Humans; D000090463:Iron Deficiencies; D016778:Malaria, Falciparum / Q000453:epidemiology*; D008295:Malawi / Q000453:epidemiology; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology*; D011990:Receptors, Transferrin / Q000097:blood; D018570:Risk Assessment
chemical_list: D000017:ABO Blood-Group System; D006451:Hemoglobin, Sickle; D011990:Receptors, Transferrin; D005293:Ferritins; D005954:Glucosephosphate Dehydrogenase