title: Depleted iron stores without anaemia early in pregnancy carries increased risk of lower birthweight even when supplemented daily with moderate iron.
abstract: BACKGROUND
  Gestational iron-deficiency anaemia has adverse pregnancy outcomes. Antenatal iron supplementation can be beneficial in anaemic women, but the effects in non-anaemic women are controversial. This observational study assessed the relationship of maternal iron stores (depleted or non-depleted) at gestational Weeks 8-12 with birthweight, in non-anaemic pregnant women following the guidelines of the Ministry of Health of Spain.
  
  
  METHODS
  Healthy, non-anaemic pregnant women (n = 205) were studied. At the first antenatal visit, a general clinical assessment was conducted, and basal blood taken. Women were classified as having non-depleted or depleted iron stores [serum ferritin (SF) < 12 µg/l)]. Daily antenatal iron supplements (48 mg on average) were started at 17 (range: 16-18) weeks. Blood haemoglobin, SF and transferrin saturation (TS) were measured in each trimester.
  
  
  RESULTS
  Of the study sample, 20, 54 and 66% had SF < 12 µg/l in the first, second and third trimesters, respectively. The prevalence of iron-depletion (SF < 12 µg/l) and iron-deficiency (SF < 12 µg/l and TS < 16%) was greater during the entire pregnancy in women with initial iron depletion versus no depletion (81.6 and 73.7% versus 61.7 and 55.4%, respectively, in the third trimester, P < 0.05). Women with initial iron-depletion delivered babies weighing on average 192 g less than that with initial iron stores, after adjusting for confounding variables (P = 0.028).
  
  
  CONCLUSIONS
  Beginning pregnancy with non-depleted iron stores is beneficial for the maternal iron status during pregnancy and infant birthweight. These findings reaffirm the importance of health promotion to ensure that women have adequate iron stores prior to, or early in, pregnancy when supplemented with moderate daily iron doses.
authors.affiliation: IISPV, Unidad de Nutrición y Salud Pública,  Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus,  Spain.
authors.forename: B
authors.initials: B
authors.lastname: Ribot
authors.forename: N
authors.initials: N
authors.lastname: Aranda
authors.forename: F
authors.initials: F
authors.lastname: Viteri
authors.forename: C
authors.initials: C
authors.lastname: Hernández-Martínez
authors.forename: J
authors.initials: J
authors.lastname: Canals
authors.forename: V
authors.initials: V
authors.lastname: Arija
mesh_terms: D000328:Adult; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007501:Iron / Q000097:blood; D000090463:Iron Deficiencies; D008137:Longitudinal Studies; D011247:Pregnancy; D011248:Pregnancy Complications; D011261:Pregnancy Trimester, First / Q000097:blood; D012307:Risk Factors
chemical_list: D007501:Iron