Back Pain in Early Pregnancy

Hormonal changes can cause sacroiliac joint pain

Up to 50% of pregnant women complain of back pain in early pregnancy. Pregnancy causes a change in hormone levels,estrogen (oestrogen in the UK) levels are altered and in particular a hormone called relaxin is released. Relaxin is important as it allows the joints in the pelvis to move, enabling the baby to be accommodated in the pelvis and essentially allowing it to come out when the time is right.

To understand the importance of this it’s worth taking a look at the anatomy of the pelvis.

Pelvic anatomy and the Sacroiliac Joints

The pelvis is made up of two large bones, the ilium, and they attach to the sacrum at the back of the spine. Where the ilium and the sacrum meet, is the sacroiliac joint.

The sacroiliac joint is a pretty special joint, normally it barely moves at all. It’s a very stable joint. This is partly due to the shape of it – both the surfaces of the ileum and the sacrum are knobbly and fit to together very snugly. Further support for the joint comes from very large strong ligaments and from some of the key muscle groups that surround it.

In order for the baby to be born the sacroiliac joint needs to move so that the two halves of the pelvis can adjust and allow delivery. This is the role of the hormone relaxin, it causes the ligaments supporting the joint to soften and allow movement. As your pregnancy progresses this relaxing of the ligaments increases. Combined with changes in your centre of gravity and increased weight because of the baby the likelihood of back pain increases.

It’s also worth thinking about the effect of the hormone relaxin on the other ligaments in the back. It is not selective, all ligaments become lax, even your knee joints when you are pregnant. So it’s not really surprising that back problems during early pregnancy occur.

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

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

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).

From Back Pain in Early Pregnancy to Lower Back Pain Toolkit Home Page

Pregnancy Back Pain Overview

Causes of Back Pain in Pregnancy

Treatment of Lower Back problems during Pregnancy

Pregnancy and Back Pain - Sacroiliac Joint Dysfunction

Sacroiliac Joint Dysfunction

10-Oct-2011