As your baby grows, your belly grows— and as your belly grows, your back takes on more and more strain as it holds you up and adjusts to your changing body. The majority of pregnant women will experience back pain— most often low back pain— at some point during their pregnancy. It is most common during the second half of pregnancy, as your baby grows bigger. These are some of the most common causes and treatments of back pain during pregnancy.
During pregnancy, a hormone called relaxin is released. Relaxin increases flexibility, relaxing the pelvic area and preparing it for birth. Studies show that relaxin is involved in the development of pelvic pain and back pain during pregnancy. In fact, there is a clear association between high relaxin levels and symptoms of pain during pregnancy— meaning that the higher the relaxin levels, the greater the pain.