If you ask Dr. Google, you'll learn that the ligaments in the foot are loosened by the pregnancy hormone Relaxin and get stretched out under the increased weight of your added pregnancy bump and curves. And you might even read that it's a permanent change.
Well that's the not the whole story. Foot woes are not inevitable nor are they necessarily permanent, nor the result of pregnancy's raging hormones (despite what Dr. Google says!).
Foot "Volume" Increases
A while back some researchers in Vermont, studied pregnant women's feet throughout their pregnancy, measuring length and width, as well as foot volume. They were trying to determine if foot changes were the result of ligament laxity as commonly assumed (you've probably heard of that Relaxin hormone that gets blamed for almost everything uncomfortable in pregnancy!) or soft tissue accumulation. What they found was that for this group of pregnant women there was no significant measurable change in width or length at the level of the skeleton, but there was an increase in foot volume by several milliliters, and that increased volume decreased only slightly postpartum. They conclude from their results that the women in their study were most likely experiencing changes in foot size based on retention of fluid and accumulation of adipose tissue (fat) and the structures of the foot itself (based on their measurement of boney prominences) had not changed. And the hormone relaxin was off the hook this time (see also The Morning After for a peek at the shift in scientific understanding of the role of this hormone).
Your foot shape might change
A few newer studies out in 2013 have looked at the change in feet during pregnancy as more lasting, and they look more specifically at changes in the height of the foot arch. A pilot study published in 2013 measured the width and length, as well as heel width and arch height of pregnant women at 3 points in pregnancy, finding measurable changes. Changes in foot length (when not weight bearing) were minimal and the most notable change was a decrease in arch height and a trend toward pronation. Another study out in 2013 measured similar changes in arch height and trend toward pronation, and found that these changes in foot arches did not disappear postpartum in the women studied. Neither study measured foot volume, which had already been established as interfering with measurements of arch height in pregnant women.
(A cool little exercise to show you how to change the measurable length of your foot by playing with your foot arches.)
One of the most documented changes in women's feet while pregnant is a shift in which part of the foot is experiencing the most pressure. Our feet support the weight of our body, but that weight isn't necessarily distributed evenly over the foot (nor do we want it to be). Researchers have consistently found that through the progression of pregnancy, plantar (bottom of the foot) pressure shifts more to the mid and forefoot.
How we align our bodies impacts how our weight is distributed over our feet. If your body weight shifts forward, more pressure will be experienced over the mid (the arches) and forefoot (more toward the toes). Biomechanist Katy Bowman writes that when our body weight shifts forward "the burden is great on the forefoot (front of the foot), overloading tiny muscles that should be concentrating on supporting the arch of the foot – not the weight of the body. This weight on the front of the foot can contribute to plantar fasciitis, hammertoes, metatarsalgia (pain in the base of the toes), and neuropathy."
While the weight gain in pregnancy certainly is most dramatically visible in that belly and challenges our ability to keep our weight back in our heels, it is not impossible to keep your weight in your heels. In fact, that's where your weight belongs. Keeping your weight back helps build the musculature you need in the back of your body to support yourself (see katysays.com ).
The most important way you can protect the integrity of your foot or restore it is to keep the musculature of the feet active and your body aligned. This applies to pregnant women, postpartum women, mamas who's babies are heading to college already, or just about anybody with feet.
- Step 1. Keep your weight in your heels. Most of us tend to wear our pelvis out in front of us. Pregnancy exacerbates this tendency. Back it up! Back up your pelvis until your weight is centered over your heels. (See Mind Your Pelvis for more.)
- Step 2. Be Barefoot and Pregnant as often as possible. Barefoot and pregnant is awesome. As often as you can. Going barefoot allows you to develop the musculature of your feet functioning optimally -- like your own, private, built-in arch support.
- Step 3. Speaking of heels….Lose 'em! Most pregnant women gravitate away from dramatic shoes with higher heels, but any shoe with a positive heel shifts your bodyweight forward and puts more pressure on that mid foot ("positive" only because it raises your heel higher than your toes). Even most athletic shoes have positive "heels" built into the shoe -- our eyes are just not trained to see it. If you chronically wear higher heels, start opting for the lowest heels you have and then transition into shoes that are totally flat ("zero rise").
- Step 4: Externally Rotate! Now that you've got your weight back over your heels, you've got to get those thigh bones back to neutral. There is a direct connection between the arch of your foot and your habitual positioning of your thigh bones. Chances are your thigh bones are internally rotated. Check out this "all about your knees" video for a tutorial in finding a neutral thigh bone. (Which also has some great insight on hyper-extended knees!)
- Step 5: Consult a Restorative Exercise Specialist. A RES-CPT can help you assess what is going on with your feet and larger alignment patterns. They can give you exercises to restore strength to your feet. (WARNING: you may not want to fit back into your pre-pregnancy shoe collection once you're hooked on alignment and natural movement.)
Foot pain can and does get in the way of the most basic things -- such as being able to walk. Which means it gets in the way of you moving your body and having a healthy pregnancy. And it gets in the way of your postpartum recovery. And it gets in the way of you keeping up with your wee ones as they grow.
But foot pain and changes also mean that something is going on in your body alignment that is sub-optimal. These changes affect not just your feet -- in fact sometimes we don't even feel it there. We can end up with knee and hip pain and joint degeneration, pelvic floor issues, unstable pelvic joints, and back pain…just to name some major problems.
Our feet are the foundation of our body. Ground zero. The optimal functioning of all the parts "above" those feet depend on the functioning of those feet.
- Segal NA1, Boyer ER, Teran-Yengle P, Glass NA, Hillstrom HJ, Yack HJ.J " Pregnancy leads to lasting changes in foot structure" Am J Phys Med Rehabil. 2013 Mar;92(3):232-40.
- Gijon-Nogueron GA1, Gavilan-Diaz M, Valle-Funes V, Jimenez-Cebrian AM, Cervera-Marin JA, Morales-Asencio JM. "Anthropometric foot changes during pregnancy: a pilot study." J Am Podiatr Med Assoc. 2013 Jul-Aug;103(4):314-21.
- Alvarez et al. "Dimensional Changed of Feet in Pregnancy." The Journal of Bone and Joint Surgery. 1988 Feb;70(2):271-4.
- Gaymer,C. Midfoot Plantar Pressure Significantly Increases in Late Gestation. . 2009 Jun;19(2):114-6