I had to get a shield at the hospital for my son. He was an aggressive eater and caused my nipples to bleed. I was about to give up on feeding cause it was so painful. Then the lactation nurse said lets try a shield and see if it helps. It was a life savor. It wasn't hard to transition after my nipples had healed up and he had learned to latch correctly. They are to your size so you can find the right fit for you. Would not listen to people that say it's too hard to transition.