Dirty Diaper Changes

Hello Ladies! When does a baby start to poop less? My LO is 10 weeks and usually would have a poopy diaper at almost every change. However, over the past day I noticed she may go a few diapers in between a poopy one with just pee. I'm wondering if that has to do with her getting older or should I be alarmed? She's breastfed and has had her normal appetite.