title: Dose-response association between maternal body mass index and small for gestational age: a meta-analysis.
abstract: OBJECTIVE
  This study was performed to determine the dose-response relationships between maternal anthropometric variables and risk of small for gestational age (SGA).
  
  
  METHODS
  Linear and nonlinear dose-response meta-analyses were performed to summarize the adjusted relative risks of SGA. Ten databases, including PubMed (MEDLINE), were searched. Study quality was assessed using the Newcastle-Ottawa scale.
  
  
  RESULTS
  A total of 323 243 subjects were extracted from high-quality studies to evaluate maternal body mass index (BMI) (n = 9). The generalizability of the findings regarding height and weight (n = 3 and 2, respectively) was limited. The non-linear model (p for non-linearity < 0.05) showed a significant and inverse association of maternal BMI with risk of SGA, although only two of nine studies involved obese women (i.e. BMI ≥ 30 kg/m2). The slope of the dose-response curve between maternal BMI and SGA (i.e. the amount of reduction in SGA risk) decreased gradually.
  
  
  CONCLUSIONS
  SGA risk may be reduced by increasing BMI of normal (i.e. 18.5 kg/m2≤ BMI < 25 kg/m2) and overweight women (i.e. 25 kg/m2≤ BMI < 30 kg/m2), but the most marked reduction is achieved by increasing BMI of underweight women (i.e. BMI < 18.5 kg/m2).
authors.affiliation: a Department of Medicine and Public Health , Nagoya Medical Science Research Institute , Nagoya , Japan.
authors.forename: Eita
authors.initials: E
authors.lastname: Goto
mesh_terms: D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D011247:Pregnancy; D011248:Pregnancy Complications; D012307:Risk Factors
keywords: Anthropometry; body mass index; meta-analysis; risk; small for gestational age