Research Article| Volume 147, ISSUE 1, P25-28, November 2009

Postural sway changes during pregnancy: A descriptive study using stabilometry



      This study aims to analyse changes in body sway over the course of pregnancy.

      Study design

      This is a descriptive study in which stabilometric tests were applied at three stages of pregnancy and with a combination of different visual conditions (eyes open/closed) and support base configuration (feet together/apart). Twenty healthy pregnant women participated in the study. Changes in postural control with pregnancy were analysed via the elliptical area of the stabilograms and spectral analysis of the displacements of the centre of pressure (COP) along the lateral and anterior/posterior directions.


      The elliptical area encompassing the COP significantly increased over the course of the pregnancy for the feet apart and eyes closed test protocols. The spectral analysis revealed a significant increase of COP oscillations along the anterior–posterior direction when subjects stood with the eyes open/feet together and feet apart. A reduction (significant) of the lateral oscillations of COP was observed for the eyes open/feet together protocol.


      Pregnancy induced significant changes in the postural control when pregnant women stood with a reduced support base or with eyes closed.


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