Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Hated these!

Like many of the other reviewers here I tried these because my son was spitting up a lot. With the Stage 1 nipples he wouldn't get anything out and end up getting so frustrated that he was nearly inconsolable. With the Stage 2 nipples the milk came out so fast that he choked. They need a Stage 1 1/2 nipple. I didn't use them long enough to see if they leaked or not. Very frustrating product. I solved his spitting up problem by using the orthodontic nipple by Medela.