Causes of Lower Back Pain in Pregnancy

Lower back pain in pregnancy is very common. It is estimated that as many as 50% women will develop some kind of back problem during pregnancy. The symptoms comes from a variety of structures including sacroiliac joints, lower back structures and sometimes the sciatic nerve .There are a few different reasons why this might happen..

Big hormone changes are taking place

In order to give birth and let a relatively large object (baby) through the narrow pelvic canal the pelvic bones have to be able to move and widen. To enable this the body releases a hormone called relaxin which causes the bodies ligaments to soften and relax. This affects the whole body including the lower back but it especially affects the sacroiliac joints. The sacroiliac joints are supported by large, tough ligaments and these ligaments must soften to allow delivery.

The pelvis and sacroiliac joints - back	Front

This is what you need when you are giving birth but the effects are not so good both before and after birth as the large, strong ligaments supporting your back and sacroiliac joints are not so supportive.

To make matters worse if you had poor muscle tone, so less supportive core stability muscles, or a history of back pain before getting pregnant its more likely that you will get back pain in pregnancy.

During pregnancy a lot of weight is gained - and it’s mostly at the front

This means that your posture has to rapidly adapt to compensate for this. This happens by increasing the hollow or the lordosis in the small of your back

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I recently saw a news item that looked at the difference between male and female spines and discussed how women’s spines have adapted to cope with these changes in order to reduce lower back pain in pregnancy (1)

Changes in the blood supply to the muscles and joints make them more vulnerable and so repetitive lifting or bending during pregnancy may worsen your lower back pain problem.

The other important thing to consider is that women who are pregnant can get all the regular types of back pain too and that it may not be related to pregnancy at all. This section on the cause of lower back pain outlines the different types of back problem all of us have to deal with.

What can you do about it?

One of the things that might help is wearing a low back corset or support. Some research (see below) has looked at the Bellybra and found that it helped reduce sacroiliac joint pain in pregnancy.

There are other types of pregnancy support on the market. Type *maternity support into the search box on the right to see what is available at Amazon.

 

References

Kalus, S.M., Kornman, L.H. & Quinlivan, J.A. Managing back pain in pregnancy using a support garment: a randomised trial. BJOG 115, 68-75 (2008).

Ho, S.S.M. et al. Effectiveness of maternity support belts in reducing low back pain during pregnancy: a review. J Clin Nurs 18, 1523-1532 (2009).

Pregnancy Back Problems Overview

Treatment of Lower Back Pain during Pregnancy

Lower Back Pain Toolkit Home Page

References

1. Whitcome, K. K., Shapiro, L. J. & Lieberman, D. E. Nature advance online publication, doi:10.1038/nature06342 (2007)

Online Pregnancy Resources

Running Moms is a nice website with lots of helpful tips and advice about running while pregnant.

10-Oct-2011