It can be quite tricky measuring a small baby, trying to manage those wriggly limbs, especially if you’re trying to do it on your own. In the early months a health care professional will monitor your baby’s measurements to check they’re growing at a healthy rate. It’s also really helpful to know how to measure a baby at home, because you’ll need their measurements when it comes to buying the right size baby clothes.
Babies grow so fast in the first few months, and what fits nicely one day can be too snug the next week. We have been looking at baby clothing sizes and how they relate to what babies wear. The main three measurements are height, weight and head circumference.
How to measure a baby – height
The length (height) of a baby helps to work out what size baby clothes will fit baby best. When measuring its best to lay your baby on a flat surface. Mark on the surface the top of the head, and gently pull the legs to full length and mark the heel position. It’s easier to take this measurement if you have another pair of hands to help you. Once you’ve marked out the two measurements, measure in centimetres from one point to the other to get the height value.
How to measure a baby – weight
Its unlikely you’ll have a baby weighing scale at your home, but if you have a scale that you stand on to weigh yourself, then this can be used to weigh your baby. It won’t be as accurate as weighing your baby directly on a weighing scale but it’ll be a good indicator. First stand on the scale and make a note of your weight. Then weigh yourself carrying your baby, and subtract the first weight (of just yourself), from the combined weight of you and your baby, the difference is your baby’s weight.
How to measure a baby – head
With a narrow tape measure, measure around the widest part of the head just above the ears.
What do percentiles mean
When your healthcare professional takes your baby’s measurements they will reference the measurements against percentiles. This is how your baby’s size relates to 100 babies of the same age. The age is recorded first and then the measurement taken against the percentiles which range from 0.4th to 99. 6th. If your baby is in the, for example, 75th percentile, it means the measurement taken indicates that your baby is the same as or heavier/taller/bigger than 75 other babies of the same age.
Baby clothes sizing
The 75th percentile sizing is often used in baby clothes sizing to create clothing that allows room for your baby to grow into.
When choosing baby clothes, first look at the clothing size chart, as this tells you what measurements your baby should be within or under, so the clothing fits. For example if your baby measures 62cm tall, and the clothing size has the height at 68cm, then there will quite a bit of extra room on the length for your baby to grow into.
Even with the correct size on small babies, when you put a sleepsuit on, it may feel like there is too much fabric in the legs, especially when the legs are more likely to be in a bent position rather than extended, but you need to make sure that there is enough room for baby to stretch their legs out without any restriction by the clothing being too short. It’s always better to be a bit bigger than too small.