It’s hard, to sum up, what happens to your body during pregnancy, labor, and delivery but simply put, having a kid is a major athletic event. It is likely the most impressive physical accomplishment of your life (unless you have multiple kids). It is a huge demand placed on an often underprepared body and if you had any vulnerability, having a kid is going to bring all of it to the surface if not in pregnancy, definitely in postpartum.

I say all of this not to scare you but just to prepare you and to help you recognize what an amazing feat your body is doing by growing a child and getting it out of you. With this outlook, it makes it obvious that we should be training for pregnancy, labor, and delivery, and then once the kid is out, following it up with slow and intentional rest, repair, and rehabilitation. It’s almost crazy to think that we often expect the body to just bounce back after all of it.

By being pregnant, you are inherently on a steady decline in many regards but there is still a lot that you can do to minimize the long-term consequences of the necessary physical changes that occur in order to grow a baby. The topics I go over and the things you are going to work on will be almost the same in your early postpartum rebuild only then you will be on the upward side of the slope. So take in what you can and do what you can but also, if you feel like crap or have a toddler running around or just don’t have the capacity to do anything that I cover here, that’s totally ok. It’s never too late to start and the opportunity to work on this stuff will be here when you are ready and able to do it.

Ok, let's get into what is going on in there and how your body is changing. The most obvious physical change is weight gain. On average you will have a 20-25% increase in your body weight but some of us (myself included) will pack on those pounds like nobody's business. So why state the obvious? What you might not be aware of is how this affects your musculoskeletal system. This 20% weight gain can increase the force on a joint by as much as 100%. Crazy right? In addition to the compressive forces on the joints, muscles also have to respond to the increase in demand but due to the inherently uneven distribution of the weight (aka mostly belly), certain muscles are responsible for all of the load. Specifically, the ankle and hips have to do a ton more work. There are also structural adaptations occurring to both make room for that baby and remain upright with the center of mass changing. This also affects which muscles are available to stabilize. The hips start to veer in front of the shoulders changing the natural curvature of the spine resulting in even more compression of the spine than the weight would alone. By the third trimester, the uterus is usually at the height of the rib cage so the baby is officially taking up as much room as is allowed for but this is also when fetal growth accelerates. At this point, the rib cage has to flare upward and widen to make more room. The soft tissue that gives way to allow for further expansion is the linea alba (the line that separates the abdominals) and this my friends is why 100% of people will have diastasis recti in their 3rd trimester. It's also why the abdominals take a trip to Hawaii. They are useless in this stretched position. So here we have a situation where there is an increase in demand with the increased load and yet, there are fewer muscles capable of increasing their capacity to meet that demand. Some might say this is poor design. Maybe we were meant to remain on all fours. Just saying.

The not-so-obvious change in our musculoskeletal system is ligament laxity. This means all the things holding your bones together are looser than they once were. This enables your pelvis to open up beyond what it has previously been able to. Again, small hole, big baby coming out of it. Now some of you might be extremely aware of this especially if you are having pubic symphysis separation while others have no idea this is happening other than being warned not to overstretch during this time. The hormone responsible for this is relaxin and it increases in every pregnant person. So why are only some acutely aware of it while others have no problem? Remember how I mentioned vulnerabilities come to the surface? Maybe it's a muscle imbalance, maybe an old injury that never fully went away, this perfect storm is going to bring it to the surface. You have increased demand with weight gain in an uneven way, you have increased movement from ligament laxity and your main stabilizer (aka your abdominals) are offline because they are stretched out. If you were previously getting away with anything, you aren't now. This is why almost 100% of pregnant people will have a musculoskeletal complaint at some point of their pregnancy and up to 1 out of every 4 will have debilitating pain. Welcome to why I have a job. I don't want this to instill any fear or concern or dread. I more just want you to know the why behind all of this. Sometimes when we know the why it's less scary and easier to manage. Also, I will be going over all the things you can do about it. Both now but especially after the baby is earthside.

There are many more changes occurring beyond the musculoskeletal system. In fact, pregnancy results in some sort of the change in every system. It's literally a full-body event. I'm not going to go into all the details but I do want to point out some of the most impressive changes. Three to four pounds of that weight gain is blood. Our blood volume increases by 50% during pregnancy. Mind-blowing right? This explains a lot of symptoms you might be experiencing including an increase in your resting heart rate to pump that extra blood all around and an increase in your respiratory rate to oxygenate all of it. Another reason our breathing rate increases is because we start to get a decrease in lung capacity once the baby takes up all the room that is usually used by the diaphragm to contract and the lungs to expand. Ironically, our blood pressure decreases during pregnancy. Remember that hormone relaxin we talked about? It has a systemic effect so it actually decreases the resistance in our blood vessels thus decreasing the blood pressure. At a certain point, the uterus also gets in the way of blood returning to the heart contributing to this decrease and this explains why you may have to transition from lying to sitting or sitting to standing a little slower to avoid getting lightheaded. In addition to needing more fluid for all this blood, our kidneys are filtering 50% more to get rid of the waste that baby and you are producing so drink your water. I was never a water drinker but found my thirst was incredible during pregnancy. This is why. More blood and more filtrating also lots more peeing.

I hope by hearing some of these details you have more of an appreciation for what your body is doing even when it feels like it is failing at life. I also hope you are beginning to understand how impressive this whole thing is and that there is a lot of rebuilding to be done once you’re on the other side of this growing a baby business.