Some women experience pain in the pubic bone and lumbosacral area during pregnancy, with restricted movement, and the pain can be aggravated by activity and relieved by bed rest This may be related to changes in maternal hormone levels caused by pregnancy, and estrogen and relaxin can cause loosening or separation of the pubic symphysis, which can cause pain, and this pain will gradually increase as the weeks of pregnancy increase and the uterus and fetus grow larger.