3 wk old won't poo without the aid of suppositries

[GetToFalkirk]

We came home from hospital and he pooed out the last of the meconium but then didn't poo for 5 days. Went to the docs and he prescribed glycerin suppositries. They worked immediately. Poo was loose (not hard as expected).
He didn't poo again so we used the suppositries again with success. However, no matter how long we leave it he won't poo without them. He passes wind and you can also see him trying to poo but nothing happens.
Has anyone an idea what could be wrong? We've spoken to the doctor and he said just to carry on using them. I think there must be something wrong as this surely isn't right. Help?

how is your baby being fed?

Congratulations btw

After a few weeks I don't think it is uncommon for exclusively breastfed babies to poo very infrequently. Two of my three dcs would only poo approximately once a week (sometimes once every 10 days) until they were about 5 months old. There was nothing wrong with them. I've seen lots of threads on MN where other mums have had the same experience. I can't remember at what stage infrequent pooing started with my dd1, but certainly it had kicked in with dd2 by 3 weeks.

Thanks. He's mainly bf but he also has 2 x 2oz bottles of formula a day. He does seem to be uncomfortable when he hasn't pooed and is much more relaxed after pooing.
When he does go, he poos a fair amount even after 1 day.