title: Maternal and perinatal characteristics and the risk of cow's milk allergy in infants up to 2 years of age: a case-control study nested in the Finnish population.
abstract: This study examined whether maternal background and perinatal factors were associated with the risk of cow's milk allergy (CMA) in infants up to 2 years of age in a nested case-control study. All children born in 1996-2004 in Finland and diagnosed with CMA by 2006 were identified (n = 16,237). For each case, one matched control was selected. Information on maternal and perinatal factors was derived from the Medical Birth Register. The associations were analyzed by conditional logistic regression. Cesarean section (adjusted odds ratio (OR) = 1.18, 95% confidence interval (CI): 1.10, 1.27) and high maternal age (> or =35 years; adjusted OR = 1.23, 95% CI: 1.11, 1.36) were associated with increased risk, whereas low maternal socioeconomic status (adjusted OR = 0.65, 95% CI: 0.59, 0.71), smoking (adjusted OR = 0.72, 95% CI: 0.67, 0.79), high number of previous deliveries (> or =5; adjusted OR = 0.71, 95% CI: 0.59, 0.86), and multiple pregnancy (adjusted OR = 0.70, 95% CI: 0.60, 0.82) were associated with decreased risk of CMA. In conclusion, maternal background and perinatal factors may play a role in the development of CMA, but further research is needed to clarify these associations and the underpinning biologic mechanisms.
authors.affiliation: Department of Health, Functional Capacity and Welfare, National Institute for Health and Welfare, Helsinki, Finland. johanna.metsala@thl.fi
authors.forename: Johanna
authors.initials: J
authors.lastname: Metsälä
authors.forename: Annamari
authors.initials: A
authors.lastname: Lundqvist
authors.forename: Minna
authors.initials: M
authors.lastname: Kaila
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
authors.forename: Timo
authors.initials: T
authors.lastname: Klaukka
authors.forename: Suvi M
authors.initials: SM
authors.lastname: Virtanen
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D016022:Case-Control Studies; D002417:Cattle; D002585:Cesarean Section / Q000706:statistics & numerical data; D016001:Confidence Intervals; D005260:Female; D005387:Finland / Q000453:epidemiology; D005512:Food Hypersensitivity / Q000453:epidemiology / Q000209:etiology*; D005865:Gestational Age; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D008892:Milk / Q000276:immunology*; D009035:Mothers / Q000706:statistics & numerical data; D016017:Odds Ratio; D010298:Parity; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects; D012959:Socioeconomic Factors; D055815:Young Adult