Should I be worried that my baby is in a low weight percentile?

My paediatrician told me my exclusively breastfed baby is only in the 25th percentile for weight. Should I be worried that he’s not gaining enough?

Many parents are concerned if their child is less than the 50th percentile for height or weight, but half of us are less than the 50th percentile. If your child is in the 25th percentile for weight, this means he’s heavier than 25 percent of boys his age, and less heavy than 75 percent of boys his age. Kids, like adults, come in all shapes and sizes, and some fall on the heavier side, some on the lighter side. It is not only nutrition that plays a role but genetics as well. For instance, two naturally slim parents will likely have a slim child. (Of course, not every kid will have the same body type as their parents, and there is lots of variability.) If your baby is satisfied after a feed, is happy and playful, and is tracking along the 25th percentile (or even lower), then you should be reassured that your child is growing well. But if your baby is irritable, difficult to console, a poor sleeper and lethargic, it’s possible he’s still hungry, and you should talk to your paediatrician about supplementing with formula or seeing a lactation consultant for help. If your baby was in the 50th percentile or higher and is now in the 25th, this is also something to discuss with your doctor. It could mean he is losing weight or not gaining enough weight to maintain his percentile. A drastic change in percentile could be cause for concern.

Read more: An age-by-age guide to your baby's eating habits Is my child growing normally?