Can we blame them for their worry though? If baby drops more than 10% of their birth weight in the first week, doctors immediately start telling the mom to supplement (not taking into account the possibility of inflated birth rates due to IV fluids during birth or the smile effect). At every appointment, we compare babies to other babies to see if they’re gaining on track. What if your baby is different, but completely normal? Why don’t we take things like short parents into account for height percentiles? I’m not saying that these can’t be good indications that something is wrong, but they’re not definitive.
Our culture is used to using bottles. When you’re giving a baby a bottle, it’s easy to see how much they ate. Fill the bottle with 5 ounces and one is left when they’re done? They ate 4 ounces. Nurse for 20, 30, or even 60 minutes and who knows how much they got. Breasts are not see through, nor do they have ounces marked.The most common growth charts compare babies to mostly formula fed babies in Ohio who were given solids around 4 months. Even using the WHO charts doesn’t necessarily make sense. Every baby is different. There’s a whole range of normal. There’s really no good comparison to a baby besides itself. Is baby gaining consistently, even if they’re on the small side? Does baby have an adequate amount of wet and dirty diapers? What does mom think about her baby’s weight gain and overall health? These are the things that tell us if we need to worry. And in the majority of cases, there is nothing to worry about.
So yes, growth charts are a useful tool in determining if there’s a problem with baby’s weight gain, but they are not the end-all be-all. Some babies are naturally big, some are naturally small (and I’ve had both), just as some adults are big and some are small. And that’s okay. So try to take a step back from the growth charts and look at the bigger picture.