title: Maternal reproductive history, fertility treatments and folic acid supplementation in the risk of childhood acute leukemia: the ESTELLE study.
abstract: OBJECTIVE
  To investigate the potential involvement of fertility treatments and other conditions of becoming pregnant (infertility, getting pregnant on birth control, maternal history of fetal loss) and folic acid supplements in the etiology of childhood leukemia (CL).
  
  
  METHODS
  The ESTELLE study included 747 cases of CL [636 cases of acute lymphoblastic leukemia (ALL) and 100 of acute myeloblastic leukemia (AML)] diagnosed in France in 2010-2011 and 1,421 population controls frequency-matched with the cases on age and gender. Data were obtained from structured telephone questionnaires administered to mothers. The odds ratios (OR) and their 95% confidence intervals were estimated using unconditional regression models adjusted for potential confounders.
  
  
  RESULTS
  CL was not associated with difficulty in becoming pregnant [OR 0.9 (0.7-1.2)], in vitro fertilisation [OR 0.6 (0.3-1.5)] or the use of any fertility treatment [OR 0.8 (0.5-1.1)] for the index pregnancy. CL was not significantly associated with becoming pregnant on contraception [OR 1.2 (0.8-1.8)], but a positive association was observed for third generation oral contraception [OR 4.3 (1.2-16.2)]; however, the result is based on small numbers. Folic acid supplementation during pregnancy was not associated with CL, but an inverse borderline association was observed for supplementation initiated in the 3 months preceding pregnancy [OR 0.7 (0.5-1.0)]. In addition, maternal histories of stillbirth and miscarriage were associated with ALL [OR 2.6 (1.1-5.9)] and AML [OR 1.8 (1.1-2.8)], respectively.
  
  
  CONCLUSIONS
  The findings do not suggest that infertility and fertility treatments are risk factors for CL. They suggest that maternal histories of stillbirth and miscarriage may be more frequent among mothers of CL cases and that folic acid supplementation during preconception may reduce the risk of CL.
authors.affiliation: Department of Environmental Epidemiology of Cancers, INSERM, Villejuif, France, roula.ajrouche@inserm.fr.
authors.forename: Roula
authors.initials: R
authors.lastname: Ajrouche
authors.forename: Jérémie
authors.initials: J
authors.lastname: Rudant
authors.forename: Laurent
authors.initials: L
authors.lastname: Orsi
authors.forename: Arnaud
authors.initials: A
authors.lastname: Petit
authors.forename: André
authors.initials: A
authors.lastname: Baruchel
authors.forename: Brigitte
authors.initials: B
authors.lastname: Nelken
authors.forename: Marlène
authors.initials: M
authors.lastname: Pasquet
authors.forename: Gérard
authors.initials: G
authors.lastname: Michel
authors.forename: Christophe
authors.initials: C
authors.lastname: Bergeron
authors.forename: Stéphane
authors.initials: S
authors.lastname: Ducassou
authors.forename: Virginie
authors.initials: V
authors.lastname: Gandemer
authors.forename: Patrick
authors.initials: P
authors.lastname: Lutz
authors.forename: Laure
authors.initials: L
authors.lastname: Saumet
authors.forename: Xavier
authors.initials: X
authors.lastname: Rialland
authors.forename: Denis
authors.initials: D
authors.lastname: Hémon
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Clavel
mesh_terms: D000022:Abortion, Spontaneous / Q000453:epidemiology; D000293:Adolescent; D000328:Adult; D001722:Birth Order; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D003270:Contraceptive Agents / Q000008:administration & dosage; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D005602:France / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015470:Leukemia, Myeloid, Acute / Q000453:epidemiology*; D008297:Male; D016017:Odds Ratio; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology*; D017584:Reproductive History; D027724:Reproductive Techniques, Assisted / Q000706:statistics & numerical data*; D018570:Risk Assessment; D012307:Risk Factors; D012959:Socioeconomic Factors; D050497:Stillbirth / Q000453:epidemiology; D011795:Surveys and Questionnaires
chemical_list: D003270:Contraceptive Agents; D005492:Folic Acid