Understanding Your Body: Changes to Expect During Pregnancy  

Pregnancy is a beautiful and life-changing experience. It is also a very physically demanding and body-changing experience! The body goes through more physical and hormonal changes during pregnancy than at any other period in a person’s life – including puberty or menopause. Understanding those changes, and what impact they will have on you both physically and mentally, will help you prepare for them, accept them, and continue to thrive through them.

First Trimester Changes

The first trimester sees a host of hormonal changes, with relatively few physical changes to the body at this point. The body begins to experience hormonal changes as soon as the implantation of a fertilized egg into the walls of the uterus occurs. The presence of the embryo signals for hormone production in the mother’s body to sustain and maintain the pregnancy. Among the hormones produced and released throughout pregnancy are relaxin, estrogen, and prolactin.

Relaxin is released to soften the connective tissues and joints within the pelvis in efforts to increase its flexibility in preparation for birth. However, there is no way for the body to target the tissues located only within the pelvis, and you will experience this increased flexibility throughout the entire body; take care to monitor your flexibility and avoid overstretching.

Estrogen, the female reproductive hormone, increases dramatically throughout pregnancy. This is the hormone responsible for making you feel emotional or sensitive, and is the culprit of any mood swings or irritability you may experience. The higher levels of estrogen also cause the pituitary gland, the part of your brain responsible for hormone production and regulation, to enlarge by 135%, causing further hormonal imbalance (read; mood swings). This growth is largely attributed to the increase in number and size of lactotrophs, the cells that produce prolactin.

Increases in prolactin levels trigger the production of breastmilk, which can cause breast tenderness. Breastfeeding mothers will continue to experience elevated prolactin levels after delivery; one of the only hormones to remain elevated after pregnancy.

These hormonal shifts can also disrupt sleep, and contribute to other common pregnancy-related symptoms such as morning sickness, nausea and vomiting, and fatigue.

Tips for managing these early discomforts include:

• pacing yourself and taking extra rest: the baby goes from a zygote to an embryo to a fetus, all within the first trimester, and all major organs of the fetus are developed – that’s a lot of work on mama, so take as many naps as you can!
• incorporate gentle movement: taking short walks and stretching – especially the hips and back – can help relieve pregnancy-related pains
• practice mindfulness: mindfulness and yoga can help reduce stress and pain – check out our post on The Benefits of Prenatal Yoga for more tips on mindfulness and yoga during pregnancy!

Second Trimester Changes

In the second trimester, there is often a much-needed respite from any nausea, morning sickness, and extreme fatigue. Many mamas get a new burst of energy in these weeks – take advantage of this time to support your body through the physical changes that are beginning and to prepare for the changes to come!

Most mamas start to see the baby bump emerge during the second trimester. Every body, baby, and pregnancy is different, and when exactly you’ll start showing is not an exact science and can vary quite a bit, though most people report a new roundness coming out sometime between 14 and 20 weeks. Whenever your baby makes their bump debut, remember to be kind to your changing body and appreciate it as the safe home for your growing babe.

The growing belly also means a shifting center of gravity; or a feeling of your balance being pulled forward by the weight of your growing baby. The second trimester is a perfect opportunity to strengthen your sense of balance with pregnancy-safe exercises to strengthen the core, pelvic floor, and stabilizing postural muscles. Be careful not to perform activities that will challenge your sense of balance (like jumping, stepping, or standing on uneven surfaces); but rather, focus on reinforcing your balance by building your core, glutes, and legs.

Your body produces a lot more blood during pregnancy – usually 50-80% more blood volume – which, along with the increase in growth hormones in your body, gives you that dewy, glowy looking skin and thicker, lustrous hair. You may also notice an increased shortness of breath at this time as your heart is working much harder to pump all that extra blood through your body. Practicing aerobic activity at a comfortable pace will help keep your heart and lungs strong and healthy, as well as keep your body prepared for labor and delivery!

Tips for capitalizing on the second trimester energy:

• strength train to prepare the body for labor and delivery: focus on building the core, pelvic floor, legs, and glutes with pregnancy-safe exercises
• build cardiovascular endurance: incorporate daily cardio activity to help the heart and lungs keep up with the increased demands of pregnancy
• practice body gratitude: learn about what your body is doing to help your baby grow healthy and strong and be appreciative – and in awe! – of everything you are capable of

Third Trimester Changes

You’re nearing the finish line, and your baby is squeezing in all the extra growth they can in the third trimester! Babies will gain about 6 to 9 pounds in the third trimester, sometimes as much as a pound per week starting around 36 weeks. This means that your body is starting to get very cramped as baby expands farther into your chest cavity, pushing into your ribcage and shoving your other organs (like your digestive tract, heart, and lungs) to the side to make room. You’ll likely experience even more shortness of breath thanks to the reduced space around your lungs, and the pressure on your digestive tract may prompt a return of nausea or indigestion.

This is a perfect time to start preparing for labor – both mentally and physically! Practicing labor breathing, meditation, and mindfulness techniques prior to labor beginning helps your body and brain to feel ready for the journey ahead and makes it easier to utilize these techniques once labor does start. We talk more about different breathing techniques for labor in our post on The Benefits of Prenatal Yoga!

Many mamas also experience other pains related to the growing baby and the pressure they exert on your body. You may have increased pelvic pressure – especially once baby “drops” in preparation for labor – or feel strain on the hips and low back from the rapidly increasing weight of baby. The last few weeks of pregnancy can become increasingly uncomfortable, so focusing on movements that will help manage your pain and prepare you for labor and delivery are essential.

Tips for preparing for labor and delivery:

• practice mindfulness and breathing techniques
• practice labor and delivery moves and poses: squat, lunge, and try to open the hips whenever possible to encourage baby to get into birthing position
• stretch and perform prenatal yoga: support and open the hips and back to relieve pain and prep for labor and delivery

In short, pregnancy is quite the adventure with lots of changes happening in your body and hormones. Knowing what to expect in each trimester can really help you handle the ups and downs. The first trimester might leave you feeling pretty worn out, but don’t worry—the second one usually brings back some of your energy. It’s super important to take care of yourself, get some gentle exercise, and practice mindfulness to help with all these changes. Remember to appreciate how strong your body is and enjoy this journey as you get ready to welcome your baby. Embrace every stage with a positive vibe and a good support system as you head toward parenthood!

What was the biggest change you were not expecting during pregnancy? Share with us in the comments below!