A new study published yesterday in the March issue of the American Journal of Physical Medicine and Rehabilitation confirms that pregnancy permanently changes the size and shape of the woman’s feet.
According to the study, the arch of the foot flattens out during pregnancy, possibly due to the extra weight and increased laxity of the joints.
"I had heard women reporting changes in their shoe size with pregnancy, but found nothing about that in medical journals or textbooks," says Neil Segal, M.D., associate professor of orthopaedics and rehabilitation at the University of Iowa, where the study was conducted.
"In order to study this more scientifically, we measured women's feet at the beginning of their pregnancy and five months after delivery. We found that pregnancy does indeed lead to permanent changes in the feet," Segal said.
Researchers of the study followed 49 pregnant women, taking static and dynamic arch measurements of their feet during the first trimester of pregnancy and again about five months after childbirth. They then found that the feet of 60 to 70 percent of the women in the study became longer and wider, with the average arch height and measures of arch rigidity decreasing significantly when comparing feet during early pregnancy to feet five months after childbirth.
The study also revealed that first pregnancies may account for most of the observed changes, while second, third, or higher pregnancies may not further alter foot structure.
"We know that women, and especially women who have had children, are disproportionately affected by musculoskeletal disorders," Segal said. "It is possible that these foot changes that occur during pregnancy may help explain why, in comparison with men, women are at higher risk for pain or arthritis in their feet, knees, hips and spines."