title: Preconceptional exposure to oral contraceptive pills and the risk of wheeze, asthma and rhinitis in children.
abstract: BACKGROUND
  The prevalence of maternal oral contraceptive pills (OCP) use and that of childhood asthma are high in western countries. The aim of this study is to examine the association of OCP use with childhood wheeze and allergic diseases in Japan.
  
  
  METHODS
  Relevant data were extracted from a hospital based birth cohort study named as Tokyo-Children's Health, Illness and Development Study (T-CHILD) of which questionnaire conducted during pregnancy included maternal history and duration of OCP use. To identify wheeze and allergic diseases in the children, the questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC) was used. Logistic regression models were applied to estimate those association and adjustments were made for maternal history of allergy, maternal education level, maternal age at pregnancy, maternal BMI, maternal smoking during pregnancy, mode of delivery, gestational age at delivery, daycare attendance, number of previous live births, and gender of child.
  
  
  RESULTS
  OCP use was associated with ever wheeze (adjusted odds ratio [aOR], 1.62; 95% confidence interval [CI], 1.10-2.40), current wheeze (aOR, 1.59; 95% CI, 1.01-2.50), ever asthma (aOR, 1.65; 95% CI, 1.02-2.65), and ever rhinitis (aOR, 1.90; 95% CI, 1.30-2.80). Compared with no prior OCP use, using OCP for more than three months statistically increased the odds of ever wheeze (P = 0.012), current wheeze (P = 0.035), and ever rhinitis (P = 0.002).
  
  
  CONCLUSIONS
  Our findings suggest that maternal OCP use has a role in the development of wheeze, asthma and rhinitis in children. Extended use of OCP is likely to increase the risk of wheeze and rhinitis.
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan; Department of Health and Psychosocial Medicine, Aichi Medical University School of Medicine, Aichi, Japan.
authors.forename: Kiwako
authors.initials: K
authors.lastname: Yamamoto-Hanada
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan; Division of Pediatrics, Nagoya Medical Center, Nagoya, Aichi, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Futamura
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan.
authors.forename: Limin
authors.initials: L
authors.lastname: Yang
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Shoda
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Narita
authors.affiliation: Department of Health and Psychosocial Medicine, Aichi Medical University School of Medicine, Aichi, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Kobayashi
authors.affiliation: Department of Allergy and Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Saito
authors.affiliation: Division of Allergy, Department of Medical Subspecialties, National Center for Child Health and Development, Tokyo, Japan. Electronic address: ohya-y@ncchd.go.jp.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ohya
mesh_terms: D001249:Asthma / Q000453:epidemiology* / Q000209:etiology*; D002675:Child, Preschool; D015331:Cohort Studies; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D016017:Odds Ratio; D063868:Patient Outcome Assessment; D011159:Population Surveillance; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D015995:Prevalence; D012135:Respiratory Sounds / Q000209:etiology*; D012220:Rhinitis / Q000453:epidemiology* / Q000209:etiology*; D012306:Risk
chemical_list: D003276:Contraceptives, Oral
keywords: Asthma; Birth cohort; Oral contraceptives; Rhinitis; Wheeze