title: Breast-feeding duration and the risk of malignant diseases in childhood in Sweden.
abstract: OBJECTIVE
  To evaluate childhood cancer in relation to duration of breast-feeding.
  
  
  METHODS
  Sweden. Records from Child Healthcare Centres were scrutinised regarding information on breast-feeding and other health-related items.
  
  
  METHODS
  All children aged 0-14 y with a malignant disease (benign brain tumours included) during the time period 1988-91 (n = 962) were identified from the Swedish Cancer Register. An equal number of controls matched for sex and age were selected from the Swedish Birth Register.
  
  
  RESULTS
  Information was obtained for 835 cases and 860 controls. Overall, duration of breast-feeding did not influence the risk for a malignant disease in this age group. However, breast-feeding > or = 1 month increased the risk for non-Hodgkin's lymphoma (NHL) yielding an odds ratio (OR) 5.5 with 95% confidence interval (CI) 1.2-25. Breast-feeding 1 -< 6 months gave OR 5.1, CI 1.1-24 and > 6 months gave OR 7.0, CI 1.3-37 with a significant trend (P = 0.04). Adjustment for maternal and birth-related co-variates gave similar results. For other malignancies no significant changes of the risk were obtained.
  
  
  CONCLUSIONS
  Overall, no association between duration of breast-feeding and childhood malignancies was found except for a significantly increased risk for NHL, but this was based on low numbers of cases and needs to be confirmed in other investigations.
authors: Department of Oncology, Orebro Medical Center, Sweden. lennart.hardell@orebroll.se
authors: L
authors: L
authors: Hardell
authors: A C
authors: AC
authors: Dreifaldt
mesh_terms: D000293:Adolescent; D001932:Brain Neoplasms / Q000453:epidemiology / Q000209:etiology; D001942:Breast Feeding / Q000009:adverse effects; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D009369:Neoplasms / Q000453:epidemiology* / Q000209:etiology; D016017:Odds Ratio; D012042:Registries; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors