A few years ago here in Argentina the advice from many/most doctors/nurses was to wake up the children and breast feed her/him every 3 hours, even if the kid was sleeping. It was insane, because the mother could not do anything and barely sleep. Not every doctor agreed with that, and I'm not sure if they changed it.

And there is also a lot of peer pressure. Other women put a funny face when someone discuss not 100% breast feeding.