Being pregnant DOES make women's feet bigger and the changes are permanent, say researchers
Study from University of Iowa found long-lasting changes to feet of pregnant women
Most changes observed in first pregnanciesReport suggests the permanent change to women's feet could lead to arthritis in later life
14:12 GMT, 3 March 2013
14:12 GMT, 3 March 2013
In her shoes: A new report suggests pregnancy can result in a woman's feet becoming permanently larger
The next time a pregnant woman puts her feet up, she might just notice they look a little bigger – and are likely to stay that way, according to new research which suggests having a baby can change your shoe size forever.
Research from the University of Iowa has found pregnancy can permanently change the size and shape of a woman's feet.
Flat feet, where the arch of the foot flattens out, are a common problem for pregnant women and is possibly caused by the extra weight and increased looseness of the joints associated with pregnancy.
But the changes could be permanent and lead to arthritis in later life, reports the American Journal of Physical Medicine & Rehabilitation.
Professor Neil Segal said: 'I had heard women reporting changes in their shoe size with pregnancy, but found nothing about that in medical journals or textbooks.
'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.'
The researchers followed 49 women throughout their pregnancy until five months after child birth.
They found that for about 60 to 70 percent of the women, their feet became longer and wider.
Arch height and measures of arch rigidity decreased significantly between early pregnancy and five months after childbirth.
The research also showed increases in foot length (between 2 and 10 mm) and arch drop.
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First pregnancies may account for most of the observed changes, while second, third, or higher pregnancies may not further alter foot structure.
Prof Segal said: 'We know that women, and especially women who have had children, are disproportionately affected by musculoskeletal disorders.
'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.'
He now plans further studies to assess whether these foot changes lead to health problems, such as arthritis, later in life.
Flat feet are a common problem for pregnant women as their bodies adjust to carrying extra weight