Static postural control assessment during pregnancy

  • Ana Silvia Moccellin
  • Fernanda G. S. A. Nora
  • Paula H. L. Costa
  • Patricia Driusso
Keywords: centre of pressure, balance, instability


The hormonal and anatomic changes during pregnancy affect the musculoskeletal system and may lead to instability of static postural control and increased risk of falls. The aim of this study was to analyze changes in static postural control during the three trimesters of pregnancy, using variables derived from the center of pressure. This is a descriptive study in which posturographic tests were applied in four still standing positions, for three trials, with a combination of different visual conditions (eyes open - EO/eyes closed - EC) and support base configurations on 20 non-pregnant women (C) and 13 pregnant women during the gestational period (G1, G2 and G3). For static postural control assessment, a force plate (Bertec®) was used, and the variables analyzed were statokinesigram area, displacement amplitude, displacement velocity and sway frequency. The results demonstrate that, early in pregnancy, the woman's body seems to already change postural control, probably due to increased mobility of the sacroiliac joint and pubic symphysis caused by hormonal factors, and during the trimesters there is a decrease in postural stability, observed as an increase in the elliptical areas, amplitudes of center of pressure displacement and velocity of center of pressure displacement.


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