What Causes Back Pain During Pregnancy?

Back pain during pregnancy is common. Approximately half of all pregnancies are complicated by back pain.1

About 10% of the time, the pain becomes so severe that it can interfere with the ability to work or carry out normal activities during pregnancy.

This article explains the common risk factors, causes, and treatments of back pain during pregnancy.

Risk Factors for Back Pain during Pregnancy

Key factors that are associated with increased risk of developing lower back pain during pregnancy include:

  • Physically strenuous work
  • Lifting, bending, and child care
  • A history of low back pain prior to pregnancy

See Lower Back Pain Symptoms, Diagnosis, and Treatment


Common Causes of Back Pain during Pregnancy

Malfunction in the sacroiliac joint is the most common cause of back pain in pregnancy. While it can be quite painful, this condition is treatable and (especially with treatment) tends to get better after delivery of the baby.

The sacroiliac joint] forms the functional unit of the pelvis that allows normal alternating movement during walking. As the pregnancy advances, hormonal changes prepare the pelvis for delivery of the child by loosening the strong ligaments that control the function of these joints.2

See Sacroiliac Joint Anatomy

The increased elasticity of these ligaments during pregnancy is necessary for the birth canal to expand as the baby passes through it. However, the associated increase in motion and instability around the sacroiliac joint can also be a source of sacroiliac pain.

See Sacroiliac Joint Dysfunction Video


  • 1.Berg G, Hammar M, Moller-Nielsen J, Linden U, Throbald JL: Low back pain during pregnancy. Obstetrics and Gynecology 71 (1): 71-5, 1988.
  • 2.Gariola DM, Tarver RD, Gibson L. Togers RE, Wase JL: Anatomic changes in the pelvis after uncomplicated vaginal delivery: a CT study on 14 women. American Journal of Roentgenology 153 (6): 1239-41, 1989.