While many women have suspected and claimed their feet got bigger when they were pregnant, Neil Segal associate professor of orthopedics and rehabilitation at the University of Iowa, and colleagues are the first to empirically determine that the majority of women’s feet do change size during pregnancy and remain a different size after pregnancy. The research was reported in the Mar. 1, 2013, issue of the American Journal of Physical Medicine & Rehabilitation.
The researchers examined 49 women’s feet during the first trimester of pregnancy and five months after delivery and found that foot size changed for 70 percent of the women studied. Most women’s feet became longer and wider. Foot length increased from two to 10 millimeters.
The change in foot size was the result of a decrease in arch height during pregnancy. A corresponding decrease in arch rigidity was also responsible for the change in women’s foot size during pregnancy. The added weight of a baby is compensated for by a variety of muscular and skeletal changes during pregnancy.
The scientists found that a woman’s first pregnancy accounted for the majority of the change in foot size.
While having a baby now has scientifically proven that a woman needs an entire new ensemble of footwear the down side is that this change in foot structure during pregnancy may also be associated with the higher risks of musculoskeletal disorders including pain or arthritis in the feet, knees, hips, and spines of women who have children.