Why is back pain so common in pregnancy?

One of the most common complaints during pregnancy is back pain. In fact, it's estimated that more than half of all pregnant people have some degree of back discomfort. Most back pain is related to the physical changes that happen during pregnancy, including hormones, changes in the center of gravity, and posture. Unfortunately, it typically gets worse as pregnancy progresses.

What causes back pain during pregnancy?

Throughout pregnancy, hormones affect a person's muscles and joints. The hormones relaxin and progesterone relax muscles and loosen ligaments and joints, especially in the pelvic area. The extra weight and body changes in pregnancy along with these loosened joints and ligaments can cause discomfort and even lead to injury. 

As your uterus grows and becomes heavier, your center of gravity changes. This can lead to problems with balance and the potential for falls. The weight of your baby and weakening of belly muscles pulls your lower spine forward, adding strain to back muscles. Many pregnant people respond by leaning back in an awkward posture. This increases back strain and pain.

What is correct posture during pregnancy?

When your body is in alignment—when you use correct posture—you can imagine a straight line running from your ears to your shoulders, and to your hips and knees. Keeping your chin tucked in and raising your head and shoulders helps you stand tall. Tuck in or tilt your pelvis forward to keep your low back from arching in a swayback position.

Choose supportive shoes with low heels and good arch support. You may need to buy a larger size, as many women find their feet grow or swell with pregnancy.

Lying down

Pregnancy hormones cause the ligaments to relax. As a result, you may feel uncomfortable, even in bed. Here are tips to help you cope:

• It’s best to not lie on your back, especially in late pregnancy, when the weight of the heavy uterus can press on the large blood vessels in your belly.
• When lying on your side, keep your body in line, with your knees bent slightly, and don't twist.
• Use pillows for support behind your back, between your legs, and under your belly. Most women find that a firm mattress with a good pad provides the best support.
• To get out of bed, raise your upper body with your arms and hands to a sitting position, then move your legs over the side of the bed. Stand up slowly, using your leg muscles.

Sitting

If you work at a desk, correct posture is especially important. Here are tips to help you practice good posture:

• Keep your body in alignment while sitting and try not to slump or slouch. Use a sturdy chair with low-back support and tilt your pelvis forward to prevent the swayback position. Your knees should be slightly lower than your hips and your feet should touch the floor.
• Choose a chair with soft arm rests that allow your shoulders to relax and your elbows to be near your body.
• Be careful with chairs on wheels as they may move as you try to sit down or stand up.
• It’s also helpful to get up every hour or so and walk around. Try not to cross your legs while seated as this can affect circulation.

Standing

Here are tips to help you use good posture when standing:

• It’s best not to stand for long periods. Try to vary your position often.
• When you do have to stand, keep your feet slightly apart and don't lock your knees. Remember to keep your pelvis tucked in.
• If you have to stand in one place for a long time, place one foot on a small step stool. This takes some of the weight off your low back. 

Prevention and treatment of back pain are important to prevent injury and to decrease the chance for long-term or chronic back pain. Because back pain in pregnancy can be a symptom of more serious problems, like preterm labor, always talk with your healthcare provider if symptoms are severe or last longer than 2 weeks.