In this video from modernmom we learn about doing abdominal exercises when pregnant. These exercises prevent lower back pain during pregnancy and when you're ready to push the baby out makes it a bit easier. On a mat, place sit balanced with your butt on the mat and place your hands behind you. Stick your leg straight out. Pull it in and crunch and lean back. 10-15 on each leg is good. This is all done sitting. Think about pulling your belly button in. Next is double leg pulls. This is a bit more advanced. The next move is a Pilates move called the can can where you twist the knees side to side 3 times then extend the legs.