How will pregnancy affect my back and pelvis?

As you get bigger, the heavier weight in front will cause the back to hunch over, easily straining your back. If you don't do anything about it, you may get chronic backache in the long run. We always tell people to try to do stretching (stretch all round). Swimming via breaststroke can also help stretch your back and relieve the pressure. The other thing that happens in pregnancy is that joints will swell a bit and pelvic girdle joint - if already lax - may have severe pain which may require painkillers for severe cases. Stretching and physiotherapy will help slowly loosen the tightness in the ligaments, which will help with the pain.