Only your baby will truly know how much milk they require, but by calculating what an average-sized baby might require at different ages, we’ve put together a guide (and it is just a guide) on daily milk requirements according to weight and age.

Remember though, that babies vary in size, stature, growth rate and energy requirements, so make sure you’re keeping an eye on your own baby’s cues and let her tell you how much she needs.

A guide to daily milk requirements

Keeping that in mind, there are two things that are frequently overlooked when estimating formula requirements:

1. Prior growth pattern

Baby’s have catch-up and slow-down growth periods that will need to be taken into account when monitoring feeding.

The reasons for a catch-up growth period could be:

• If your baby was smaller than expected at birth
• If she had been underfeeding previously for some reason

Similarly, slow-down growth could be due to:

• A heavier birth weight than expected
• Overfeeding in the early weeks

During a catch-up growth period your baby may appear ravenous and consume more formula than expected. During a period of slow-down growth your baby may start to consume less formula as her body burns excess fat stores until her size is back in line with her genetic predisposition. This might occur from the time of her birth or once her sucking reflex has disappeared; at which time she has greater control over the feed and will take only what her body needs for growth and energy.

A baby who is underfeeding will not show signs of being well nourished, whereas a baby that is just going through a period of slow-down growth will.

2. Genetic endowment

Your baby’s genetic endowment, passed on from both parents, will influence her size, shape, pattern of growth and metabolic rate (how fast she burns energy).

If your baby is of small stature, because her mother and father are shorter than average, the lower end of the range may provide a more realistic estimate of formula requirements. In contrast, if your baby is clearly going to grow very tall because both parents are above average height, then the upper end of the range might prove closer to the mark. However, this must be considered in context with your baby’s prior growth pattern.

While it’s wise to offer your baby a little more formula in her bottles than you anticipate she might need, it’s important that you respond appropriately to her feeding cues and don’t try to make her take more than she wants. If you are worried about the amount of milk your baby is taking, discuss this with your healthcare provider.