A biomechanical analysis of gait during pregnancy

There are many anatomical changes during pregnancy that could potentially lead to substantial alterations in gait. Gait deviations may contribute to a variety of musculoskeletal overuse conditions associated with pregnancy, such as low-back, hip, and calf pain. Because we are aware of little research on this topic, the purpose of this study was to objectively analyze gait during pregnancy.

Three-dimensional gait analysis was performed on fifteen women during the second half of the last trimester of pregnancy and again one year post partum. Selected kinematic and kinetic parameters for the pregnancy and one-year postpartum conditions were compared with use of paired t tests (95 percent significance level).

Overall, gait kinematics were remarkably unchanged during pregnancy. No evidence of a so-called waddling gait during pregnancy was found. Maximum anterior pelvic tilt during gait increased a mean of 4 degrees during pregnancy, although individual subject-to-subject variation (range, an increase of 13 degrees to a decrease of 10 degrees) was observed. Significant increases in hip and ankle kinetic gait parameters, however, were observed during pregnancy (p < 0.05).

Significant increases in kinetic gait parameters during pregnancy (p < 0.05) explain how gait motion remained relatively unchanged despite increases in body mass and width as well as changes in mass distribution about the trunk. This finding indicates that during pregnancy there may be an increased demand placed on hip abductor, hip extensor, and ankle plantar flexor muscles during walking.