title: Maternal homocysteine and small-for-gestational-age offspring: systematic review and meta-analysis.
abstract: BACKGROUND
  Growth retardation in utero leading to small-for-gestational-age (SGA) newborns is associated with increased neonatal morbidity and mortality and with lifelong consequences such as poor cognitive function and cardiovascular diseases. Maternal total homocysteine (tHcy) concentrations have been linked to a wide range of adverse pregnancy outcomes and could possibly influence birth weight.
  
  
  OBJECTIVE
  We performed a systematic review of and meta-analysis on the association of maternal tHcy and birth weight.
  
  
  METHODS
  A literature search of English, German, and French publications with the use of the PubMed database (January 1966-July 2010) found 78 abstracts. Search terms were as follows: homocysteine AND (birth weight OR small for gestational age OR intrauterine growth retardation). Studies were eligible if information on maternal tHcy and birth weight and the possible association between maternal tHcy and birth weight was available. Effect size estimates were converted to ORs as estimates of the RR of a woman to deliver SGA offspring when maternal tHcy exceeded the 90th percentile.
  
  
  RESULTS
  The search yielded 19 studies for analysis, consisting of 21,326 individuals. Pooled analysis resulted in a crude OR of 1.25 (95% CI: 1.09, 1.44). When this estimate was expressed as a linear effect, it corresponded to a decrease in birth weight of 31 g (95% CI: -13, -51 g) for a 1-SD increase in maternal tHcy.
  
  
  CONCLUSIONS
  Higher maternal tHcy concentrations are associated with a small increased risk for SGA offspring. The small estimated birth weight difference might be of little clinical relevance for the individual newborn; however, it could be of greater importance at a population level.
authors.affiliation: Department of Pediatrics, Radboud University, Nijmegen Medical Center, Netherlands. m.hogeveen@cukz.umcn.nl
authors.forename: Marije
authors.initials: M
authors.lastname: Hogeveen
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Blom
authors.forename: Martin
authors.initials: M
authors.lastname: den Heijer
mesh_terms: D001724:Birth Weight; D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000150:complications*; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D016017:Odds Ratio; D011247:Pregnancy / Q000097:blood; D011248:Pregnancy Complications; D011256:Pregnancy Outcome
chemical_list: D006710:Homocysteine