It's been my experience with the babies that have used the breastflow bottle that they tend to bite and compress more while nursing. Don't they have to bite/compress that blue thing inside to get the milk? Also some sippy cups require the same compression to open the slits that are vertical. Not something I choose to use. Just my 2 cents Maria Parlapiano RN IBCLC (my 3rd post today - now gotta work) Chatham, NJ *********************************************** Archives: http://community.lsoft.com/archives/LACTNET.html To reach list owners: [log in to unmask] Mail all list management commands to: [log in to unmask] COMMANDS: 1. To temporarily stop your subscription write in the body of an email: set lactnet nomail 2. To start it again: set lactnet mail 3. To unsubscribe: unsubscribe lactnet 4. To get a comprehensive list of rules and directions: get lactnet welcome