v1pro v2pro wearable breast pump replacement partsSome breast pump accessories do need replacing regularly to maintain performance. If you notice that your pump seems to have lost suction, the first thing you should do is take a look at your parts, particularly the valves, and inspect for wear, fraying, or stretching and replace if needed. 1. Diaphragm and duck valves need to be replaced every 3 months; 2. Backflow linker and flange shields need to be replaced every 6 months