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Influenza and pregnancy

Denise J Jamieson, MD, MPH
Sonja A Rasmussen, MD, MS
Section Editors
Vincenzo Berghella, MD
Martin S Hirsch, MD
Deputy Editor
Vanessa A Barss, MD, FACOG


Pregnant women with influenza are more likely to develop severe illness and to die than the general population, based on data from seasonal influenza and from the influenza pandemics of 1918 to 1919, 1957 to 1958, and 2009 to 2010. The increased severity of influenza in pregnant women is thought to be related to normal physiologic changes that occur during pregnancy. For example, heart rate and oxygen consumption increase, lung capacity decreases, and there is a shift away from cell-mediated immunity.

Because of the increased severity of influenza in pregnancy, inactivated influenza vaccine is recommended for pregnant women, regardless of trimester of pregnancy. In addition, pregnant women with suspected or confirmed influenza should receive prompt empiric treatment with an appropriate antiviral medication.


Clinical manifestations of influenza in pregnant women are similar to those in the general population, and include fever, cough, rhinorrhea, sore throat, headache, shortness of breath, and myalgia [1]. (See "Clinical manifestations of seasonal influenza in adults".)


The diagnosis of influenza should be made clinically, since it is critical to initiate appropriate treatment promptly in pregnant women. (See "Diagnosis of seasonal influenza in adults", section on 'Clinical diagnosis'.)

Diagnostic influenza laboratory tests in pregnant women are the same as those for other high-risk patients. (See "Diagnosis of seasonal influenza in adults", section on 'Approach to diagnosis' and "Diagnosis of seasonal influenza in adults", section on 'Laboratory tests'.)

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Literature review current through: Nov 2017. | This topic last updated: Oct 31, 2017.
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