Shortness of breath during pregnancy

Dyspnea (shortness of breath) is a common complaint during normal pregnancy, even in women without lung disease.

Prevalence of dyspnea during pregnancy:

  • 15% by 12 weeks
  • 50% by 19 weeks
  • 75% by 31 weeks

The mechanisms are complex and not fully understood, but are related to an awareness of the physiological increase in breathing stimulated by pregnancy.

This physiological “dyspnea of pregnancy” needs to be differentiated from lung or heart disease. Features of dyspnea of pregnancy include:

  • an isolated symptom, ie. not associated cough, wheeze, chest pain
  • does not interfere with daily activities
  • normal respiratory/cardiac history and physical examination

Additional investigations may be required to exclude respiratory or cardiac disease.


Jensen D, Webb KA, Davies GA, O’Donnell DE. Mechanisms of activity-related breathlessness in healthy human pregnancy. Eur J Appl Physiol. 2009 May;106(2):253-65

Special Pregnancy Program

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Prenatal Diagnosis & Medical Genetics

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phone: 416-586-4800 x 4523
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Perinatal Mental Health

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