title: Evaluating the relationships among maternal reproductive history, birth characteristics, and infant leukemia: a report from the Children's Cancer Group.
abstract: OBJECTIVE
  Specific events in the mother's reproductive history and certain birth characteristics have been associated with childhood leukemia. Few studies have explored these associations specifically in infants.
  
  
  METHODS
  The Children's Cancer Group (CCG) conducted three separate case-control studies of childhood leukemia that involved similar methodologies and data collection. Data from interviews of the mothers of a total of 303 children diagnosed with leukemia at 1 year of age or younger and their matched controls (n = 468) were available from the three studies. These data included maternal reproductive history (stillbirths, abortions, and miscarriages) and certain birth characteristics of the index child.
  
  
  RESULTS
  Compared with controls, cases were significantly more likely to be female (P < 0.01) and were more often heavier at birth (particularly cases diagnosed after 6 months of age (odds ratio, 4.18; 95% confidence interval, 1.75-10.02)). Overall, there were no statistically significant differences between cases and controls in regard to maternal report of any type of previous fetal loss. Finally, being a later-born child was associated with an increased risk of acute myeloid leukemia but not of acute lymphoblastic leukemia.
  
  
  CONCLUSIONS
  The relationships among birthweight, prior fetal loss, and risk of infant leukemia appear to be complex. Further studies of infant leukemia that incorporate molecular as well as epidemiologic data may help to elucidate these differences.
authors.affiliation: Division of Pediatric Epidemiology and Clinical Research, University of Minnesota, Minneapolis, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Ross
authors.forename: J D
authors.initials: JD
authors.lastname: Potter
authors.forename: X O
authors.initials: XO
authors.lastname: Shu
authors.forename: G H
authors.initials: GH
authors.lastname: Reaman
authors.forename: B
authors.initials: B
authors.lastname: Lampkin
authors.forename: L L
authors.initials: LL
authors.lastname: Robison
mesh_terms: D000293:Adolescent; D000328:Adult; D001722:Birth Order; D001724:Birth Weight; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007951:Leukemia, Myeloid / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008423:Maternal Age; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology* / Q000209:etiology; D011247:Pregnancy; D017584:Reproductive History; D012307:Risk Factors; D012737:Sex Factors