All Momcozy pump parts that come in contact with breast milk are BPA free, giving you peace of mind about your baby's milk. Some 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. Silicone accessories are recommended to replace your parts every 1-3 months. Other accessories are recommended to be replaced according to usage.