title: Pre-pregnancy iron reserves, iron supplementation during pregnancy, and birth weight.
abstract: BACKGROUND
  Early iron supplementation in women with sufficient reserves could provoke iron excess resulting in haemoconcentration and low infant birth weight (IBW).
  
  
  OBJECTIVE
  To clarify the influence of early iron supplementation on maternal iron status and the IBW, taking into account pre-pregnancy iron deposits.
  
  
  METHODS
  Longitudinal, prospective study.
  
  
  METHODS
  Healthy women volunteers (n=82) intending to become pregnant.
  
  
  METHODS
  Women were grouped as a function of their pre-pregnancy (low or present) iron stores (serum ferritin (SF)<or≥20μg/L) and time of commencement of iron supplementation during pregnancy; "early" (<20weeks) or "late" (≥20weeks). Obstetric and clinical history, smoking habit, dietary intake and iron biochemical parameters were obtained at pre-pregnancy as well as at 1st, 2nd and 3rd trimesters. Haemoglobin, MCV, SF and transferrin saturation (TS) were measured.
  
  
  RESULTS
  Overall, 36% of the women had low iron stores at pre-pregnancy. The mean early supplementation with iron was 140.7mg/d and the mean of late supplementation was 99.01mg/d. Early supplementation improves the biochemical status of the mother and does not provoke a significant increase in haemoconcentration relative to late supplementation independently of the pre-pregnancy iron levels. Supplemental iron had a positive effect on birth weight among women with pre-pregnancy low iron stores (β=4.37; SE=1.8; p=0.038) and did not affect birth weight among women with present iron stores (β=-0.008; SE=3.03; p=0.998).
  
  
  CONCLUSIONS
  Early iron supplementation with doses ~100mg/d improves the biochemical status of the mother independently of her pre-pregnancy iron status. Supplementation with iron improves newborn birth weight in those women who start pregnancy with iron deficiency, and makes no significant difference to those women who are not iron deficient.
authors: IISPV, Departament de Ciències Mèdiques Bàsiques, Universitat Rovira i Virgili (URV), Spain.
authors: Nuria
authors: N
authors: Aranda
authors: Blanca
authors: B
authors: Ribot
authors: Elena
authors: E
authors: Garcia
authors: Fernando E
authors: FE
authors: Viteri
authors: Victoria
authors: V
authors: Arija
mesh_terms: D000740:Anemia / Q000453:epidemiology; D001724:Birth Weight; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007501:Iron / Q000097:blood* / Q000627:therapeutic use; D008137:Longitudinal Studies; D016742:Preconception Care; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000453:epidemiology; D011295:Prenatal Care
chemical_list: D007501:Iron