title: Is fetal gender associated with emergency department visits for asthma during pregnancy?
abstract: BACKGROUND
  To investigate if fetal gender (1) affects the risk of having an emergency department (ED) visit for asthma; and (2) is associated with adverse pregnancy outcomes among women who had at least one visit to the ED for asthma during pregnancy.
  
  
  METHODS
  We linked two provincial administrative databases containing records on in-patient deliveries and ED visits. The study sample included women who delivered a live singleton baby between April 2003 and March 2004. Pregnant women who made at least one ED visit for asthma were counted as cases and the rest of the women as control subjects. We performed a multivariable analysis using logistic regression to model the risk of having an ED visit for asthma, with fetal gender being one of the predictors. In addition, a series of multivariable logistic regressions were also constructed separately for cases and controls for the following adverse delivery outcomes: low birth weight baby, preterm delivery, and delivery via Caesarian section.
  
  
  RESULTS
  Among 109,173 live singleton deliveries, 530 women had visited ED due to asthma during pregnancy. While having an ED visit for asthma was positively associated with teenage pregnancy, low income, and presence of pregnancy-induced hypertension, it was not associated with fetal gender (OR 1.01, 95% CI 0.85-1.19). Fetal gender was not a significant predictor of adverse pregnancy outcomes among women who had an asthma ED visit during pregnancy.
  
  
  CONCLUSIONS
  Fetal gender does not affect the risk of having an ED visit for asthma during pregnancy, and it is not associated with adverse pregnancy outcomes among women who had an asthma-related ED during pregnancy.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada. baibera@mcmaster.ca
authors.forename: Akerke
authors.initials: A
authors.lastname: Baibergenova
authors.forename: Lehana
authors.initials: L
authors.lastname: Thabane
authors.forename: Noori
authors.initials: N
authors.lastname: Akhtar-Danesh
authors.forename: Mitchell
authors.initials: M
authors.lastname: Levine
authors.forename: Amiram
authors.initials: A
authors.lastname: Gafni
mesh_terms: D000293:Adolescent; D000328:Adult; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D008297:Male; D008423:Maternal Age; D010298:Parity; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk; D011295:Prenatal Care; D011336:Probability; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012732:Sex Determination Analysis; D017678:Sex Distribution; D012737:Sex Factors