Suggest Remedy For Recurring Muscle Cramping Upon Bending

I started getting severe muscle cramping in my sides 2 years ago while pregnant, I thought it was related to changing body shape but still get hard cramps randomly when turning or bending just so,, or sometimes even just laughing. I have hyperactive thyroid and PCOS, overweight at 5'7" and 270 lbs. My routine CBC and chemistry are all WNL. Though it rarely affects my iLife significantly, I am a RN and getting one of these cramps while moving or lifting a patient could be potentially be harmful to them or me. Could you suggest a direction I should be looking in for answers?
P