Reach out with one arm and the opposite leg, then pull together under your body. Switch sides.
This move is not only a great strengthening exercise, but also a wonderful stretch for your growing body! Actual cat optional. ;)
While prone planking isn't advised after the first trimester, modified side plank is a safe way to strengthen your core.
Work your arms and core with reverse plank! From a seated position, lift your hips so they are in line with your shoulders and heels. Hold for 10 seconds.
Slightly lean back to engage your abs, then tap your heels out and back in. You can do both legs at once or one at a time.
This move can be done on the floor, in a chair, or on an exercise ball. Keep your core stable and focus on contracting your abs with each rep.
A variation on the seated march, this move incorporates a slight twist as you reach behind you.