A: Your heart is working harder than ever now to keep up with the extra blood your body is producing to help your baby grow. So at times you may feel a pounding or fluttering sensation in your chest, especially if you stand up too quickly. A pounding ticker can also be a symptom of dehydration, so check your fluid intake and be sure you're sipping at least six to eight glasses of fluids each day. This is usually normal and nothing to worry about, but if it seems like your heart is really racing, or you feel short of breath, have chest pains, or notice an irregular heartbeat, then you should give your doctor a call. Pregnant women are especially vulnerable to irregular heart rhythms, so you should discuss symptoms like these with your doctor.