Does milk come in contact with the water in the breast shield assembly? Natalie March 20, 2017 23:19 Follow The Naya Smart Breast Pump uses a closed system which prevents milk from coming into contact with the water in the system. Related articles How do I make sure my breast correctly fits the breast shield? What is the frequency of cycles? What happens if my tubing begins to leak water? Is this a regulated device? Assembly and Use of Your Pump Comments 0 comments Article is closed for comments.