Pregnancy: Has My Shoe Size Changed Or Did My Feet Grow?

03/18/2010 05:12 am ET | Updated Nov 17, 2011

Ladies, can pregnancy change your shoe size? Can pregnancy cause your feet to grow?

These are two common questions that patients always ask me during their pregnancy. The answers are, pregnancy can change your shoe size and your feet can change, becoming longer.

The reason is, a hormone called Relaxin, which is released into your blood stream during your pregnancy. The ovaries produce the hormone Relaxin during pregnancy. Its function is to cause pelvic and cervical expansion by loosening the ligament attachments in the joint between the pubic bones in the front of the pelvis and the joints between the sacrum and the pelvis in the back, allowing the fetus to travel through the birth canal. It also inhibits muscular contractions of the uterus and prevents the otherwise natural abortion of the fetus, stimulates the growth of the glands in the breasts which are responsible for milk production and increases the amount of water in the uterus. The hormone Relaxin is only found in pregnant women and remains in their body for only 24 hours after the child is born.

So the big question is what does the hormone Relaxin has to do with feet and will it affect every pregnant woman? The bones and joints in the feet are connected together by ligaments. Therefore, when Relaxin is released during pregnancy it can also target the ligaments in the feet causing them to relax and elongate. Relaxin affects the weight-bearing joints in the feet (joints in the mid-foot or arch area) and some women's feet will change in width as well as length. When these joints are affected the ligament attachments weaken and the arch can flatten causing the foot to get longer. Not all women's feet change size during their pregnancy but for the ones whose feet do it can become pretty frustrating. The change is permanent and your feet will not revert back to its original size, therefore, causing havoc in pregnant women's shoe wardrobes.

During your pregnancy if you feel that additional arch support is needed because your feet get tired from standing and carrying a little extra weight, look into over the counter arch supports such as Instant Arches or custom made orthotics. These types of foot products can help support your feet and make you more comfortable when walking and standing. The arch supports will not prevent any of the changes in your feet due to the hormone Relaxin. For those women who have experienced a change in their shoe size after their pregnancy try taking your shoes to a shoe repair shop to have them stretched.

If all else falls, then it's off to the shoe store!