Hun, 12 weeks is about the time that DS1 started pooing only every 10 days or so. DS2 started a bit later, but he also went about once every 10 days or so when he was a few months old. It is very normal, and as has been mentioned, bf babies really don't get constipated. Sometimes they do get grunty and seem to have constipation pain. I don't really know why, but it's not actually constipation, and it is normal. So you don't need to worry. The only time to worry is if a newborn doesn't poo regularly (as in for the first few weeks).