title: Risk of preterm delivery in relation to maternal low birth weight.
abstract: OBJECTIVE
  We examined the relationship between maternal low birth weight and preterm delivery risk.
  
  
  METHODS
  Information concerning maternal birth weight was collected during in-person interviews. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Preterm delivery cases were studied in aggregate, in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery, moderate preterm delivery [gestational age at delivery 34-36 weeks], and early preterm delivery [gestational age at delivery<34 weeks]).
  
  
  RESULTS
  After adjusting for confounders, women weighing<2,500 g at birth had a 1.54-fold increased risk of preterm delivery versus women weighing=2,500 g (95% CI 0.97-2.44). Maternal low birth weight was associated with a 2-fold increased risk of spontaneous preterm delivery (95% CI 1.03-3.89), but weakly associated with preterm premature rupture of membranes (OR=1.44; 95% CI 0.67-3.09) and medically induced preterm delivery (OR=1.10; 95% CI 0.43-2.82). Maternal low birth weight was more strongly associated with early preterm delivery (OR=1.94) than with moderate preterm delivery (OR=1.46). Women weighing<2,500 g at birth and who became obese (pre-pregnancy body mass index, =30 kg/m2) before pregnancy had a 3.65-fold increased risk of preterm delivery (95% CI 1.33-10.02) versus women weighing=2,500 g at birth and who were not obese prior to pregnancy (<30 kg/m2).
  
  
  CONCLUSIONS
  Results confirm earlier findings linking maternal low birth weight with future risk of preterm delivery.
authors.affiliation: Department of Epidemiology, Multidisciplinary International Research Training Program, University of Washington School of Public Health and Community Medicine, Seattle, WA 98195, USA.
authors.forename: Barna
authors.initials: B
authors.lastname: De
authors.forename: Stephanie
authors.initials: S
authors.lastname: Lin
authors.forename: Vitool
authors.initials: V
authors.lastname: Lohsoonthorn
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Williams
mesh_terms: D000328:Adult; D001835:Body Weight; D005260:Female; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D009035:Mothers; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology*; D012307:Risk Factors; D014861:Washington / Q000453:epidemiology