WADDLING GAIT AND BALANCE CONTROL DURING PREGNANCY

Zahra Abedzadehzavareh

doi:10.7273/000007303

Pregnancy induces significant anatomical and physiological changes that affect balance and gait. One common gait pattern observed in pregnant individuals is the "waddling gait," characterized primarily by a wider step width, but also linked to anterior pelvic tilt, thoracic extension, and increased trunk motion. Given these changes, my thesis explores the role of waddling gait biomechanical adaptations during pregnancy. Additionally, it aims to develop effective assessment tools for evaluating balance control in response to these adaptations. In a longitudinal study, we assessed twenty-three pregnant individuals at 4-week intervals (±two weeks) between 18 and 34 weeks of gestation. Reflective markers placed on thirteen body segments were tracked using motion capture cameras. Participants completed quiet standing and walking trials, where spatiotemporal variables, whole-body kinematics, body center of mass (COM) motion, and gait energetics were calculated. In the first project for my thesis, my research question was: is waddling gait during pregnancy a sign of poor balance, or is it a protective mechanism? I analyzed the relationship between step width (a defining feature of waddling gait) and various biomechanical parameters such as lateral center of mass motion, mechanical work, and energy recovery. My results showed a positive correlation between change in step width average and lateral motion of the center of mass during walking (R2=0.624, p<0.001) and step width standard deviation and change in minimum center of gravity distance to the lateral border (R2=0.339, p=0.004), suggesting wider steps help recapture balance during pregnancy. Surprisingly, no significant relationship was found between step width and energy recovery (p=0.341) or mechanical work (p=0.482), indicating that taking wider steps is not inefficient. A negative correlation between step width and standing anteroposterior COM motion (R²=0.315, p=0.005) suggested improved balance control in those adopting this gait pattern. This project was presented at two conferences and received the Best Poster Award for a non-PhD student at the Northwest Biomechanics Symposium (NWBS). It has also been published in the Gait and Posture journal. In the second project for my thesis, I aimed to define the “pregnant waddle” by examining the relationship between waddling gait characteristics and investigating whether changes in waddling coincide with other biomechanical adaptations throughout pregnancy. Multiple linear regression analyses were performed to determine whether specific waddling gait characteristics correlate with balance and step width, as well as to explore correlations between kinematic variables and gestation time related changes in balance and step width. My results indicated that sagittal thorax motion (R2 = 0.212, p < 0.001), lateral bending motion (R2 = 0.349, p < 0.001), and lumbar motion (R2 = 0.378, p = 0.033) were significantly correlated with step width. I also found that lateral bending motion is positively correlated with balance during standing (R2 = 0.055, p = 0.016). Additionally, changes in thorax motion were a significant correlate with step width change (β = -17.393, R2 = 0.255, p = 0.014), suggesting that an increased thorax motion during pregnancy is associated with narrower steps. Together, these two studies suggest that a waddling gait during pregnancy is a beneficial adaptation that helps to promote balance through combination of wider step width and thorax lateral bending. This adaptation increases lateral motion of the center of mass (COM), contributing to poorer balance without significant energy cost. Contrary to historical beliefs that pregnant individuals should limit their physical activity, these studies highlight that waddling gait supports balance and may reduce fall risk. This insight reframes waddling gait as a beneficial biomechanical strategy rather than an inefficient movement pattern. These insights can guide clinicians in developing targeted interventions, including abdominal support devices, while promoting waddling gait training to reduce fall risk in pregnancy.

WADDLING GAIT AND BALANCE CONTROL DURING PREGNANCY

Files and links (1)

Abstract

Metrics

Details