The hormones produced during pregnancy cause the ligaments that support your joints to become relaxed. This makes the joints more mobile and more at risk of injury. The extra weight in the front of your body during pregnancy shifts your center of gravity and places stress on joints and muscles, especially those in the pelvis and lower back. This can make you less stable, cause back pain, and make you more likely to lose your balance and fall, especially in later pregnancy. The extra weight you are carrying will make your body work harder than before you were pregnant.