Changes in foot posture during pregnancy and their relation with musculoskeletal pain: A longitudinal cohort study

To examine foot posture changes during the three trimesters of pregnancy and to determine whether there is a relationship between these changes and the pain experienced in this period.

The study sample consisted of 62 pregnant women who attended the Gynaecology Service at Hospital ​Santa María del Puerto (Cádiz, Spain), between January 2013 and May 2014. In their first visit, the following sociodemographic and anthropometric data were recorded: age, weight, height and foot size. In addition, information was obtained regarding pain in the lower back, knees, ankles and feet. In this first visit, too, the Foot Posture Index (FPI) was assessed, and three subsequent controls were performed during the first, second and third months of pregnancy (termed Stages 1, 2 and 3, respectively).

In Stage 1, the average foot size (i.e., shoe size) was 38.3 (SD 1.5). This size did not change between Stages 1, 2 and 3. However, body weight and BMI did present statistically significant changes during this period (p<0.0001). The FPI varied during pregnancy but no relation was observed between these changes and the onset of pain.

During pregnancy, pronation increases but this does not appear to influence the onset of pain in the lower limbs.