I've got the same issue. For the medical options (cortisone shot, etc.), my dr. said that I shouldn't consider those until I was done having kids--I'm currently pregnant with #2. Instead, I've got the thumb-immobilizing wrist splint, which helps, and I also ice it with a bag of peas at the end of the day. I also try to be conscious of how I pick up DD--if you just watch the angle of your hand/wrist/ arm, you'll find you can relieve a lot of the pressure and improve things just through a slight adjustment. I found that I was picking up DD under her arms by focusing the weight in the crook between my thumb and forefinger, which was causing tendonitis in my wrist and thumb. I slight adjustment--keeping my wrist straight, weight more in the palm of my hand rather than thumb--made a big difference. GL!