To turn your "ouch" into "om," try one simple move -- a modified version of the Cat-Cow pose -- before you head to the hospital. It can ease back pain and help move the baby down the birth canal during the early stages of labor, says Lisa Pedersen, a prenatal-yoga instructor and mom of two in Hermosa Beach, CA.
Get on your hands and knees. (Check that hands are underneath shoulders and knees are underneath hips.)
Inhale and gently arch your back as you lift your head and tailbone at the same time, gazing straight ahead.
Exhale and tuck your head and tailbone, hunching your back like a cat.
Repeat as often as you need to, breathing more deeply with each rep.