In general, we recommend following the below guidelines for getting started on the appropriate size Avent nipple. The MAM Baby range features four different flow sizes for teats. Confusingly their final size is called Size x, not size 4, and is an extra fast flow according to the manufacturer.

The main reason for these sizes, aside form the growth of the baby, is the fact that newborns cannot keep up with the flow of milk as fast as a baby who is six months old.The Philips Avent teats come in six different sizes. The smallest of which is ideal for preemie babies, and the range goes up to a fast flow. If you’re unsure if they’re ready, rest assured there’s no exact science to when it’s time to change up the flow rate on your baby’s bottle.

For babies who are alternating between breastfeeding and bottle usage, 1 is the recommended number of Avent nipple sizes.

Warnings

The number 1 is recommended to use regardless of the babies age if alternating between breast and bottle is the practice. If your child seems generally happy and healthy, chances are that you already have the right size nipple.