title: A prospective study of respiratory viral infection in pregnant women with and without asthma.
abstract: BACKGROUND
  Respiratory viral infections are common in pregnancy, but their health impact, especially in asthma, is unknown. The objective of this study was to assess the frequency, severity, and consequences of respiratory viral infection during pregnancy in women with and without asthma.
  
  
  METHODS
  In this prospective cohort study, common cold symptoms were assessed during pregnancy in 168 women with asthma and 117 women without asthma using the common cold questionnaire and by self-report. Nasal and throat swabs were collected for suspected infections and tested by polymerase chain reaction for respiratory viruses. Pregnancy and asthma outcomes were recorded.
  
  
  RESULTS
  Pregnant women with asthma had more prospective self-reported and questionnaire-detected common colds than pregnant women without asthma (incidence rate ratio, 1.77; 95% CI, 1.30-2.42; P &lt; .0001). Retrospectively reported common colds in early pregnancy and post partum were increased in women with asthma compared with women without asthma. The severity of cold symptoms was also increased in women with asthma (total cold score median, 8; interquartile range [5, 10] in women with asthma vs 6 [5, 8] in control subjects; P = .031). Among women with asthma, having a laboratory-confirmed viral infection was associated with poorer maternal health, with 60% of infections associated with uncontrolled asthma and a higher likelihood of preeclampsia.
  
  
  CONCLUSIONS
  Pregnant women with asthma have more common colds during pregnancy than pregnant women without asthma. Colds during pregnancy were associated with adverse maternal and pregnancy outcomes. Prevention of viral infection in pregnancy may improve the health of mothers with asthma.
authors.affiliation: Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, NSW, Australia. Electronic address: vanessa.murphy@newcastle.edu.au.
authors.forename: Vanessa E
authors.initials: VE
authors.lastname: Murphy
authors.affiliation: Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, NSW, Australia; John Hunter Hospital, Newcastle, NSW, Australia.
authors.forename: Heather
authors.initials: H
authors.lastname: Powell
authors.affiliation: Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, NSW, Australia; John Hunter Hospital, Newcastle, NSW, Australia.
authors.forename: Peter A B
authors.initials: PAB
authors.lastname: Wark
authors.affiliation: Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, NSW, Australia; John Hunter Hospital, Newcastle, NSW, Australia.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Gibson
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000150:complications*; D001315:Australia / Q000453:epidemiology; D003139:Common Cold / Q000175:diagnosis* / Q000453:epidemiology* / Q000821:virology; D005260:Female; D006801:Humans; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis* / Q000453:epidemiology*; D011256:Pregnancy Outcome; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires