Originally Posted by
QuiltnNan
Cotton shrinks because of the tension that is applied to it during the construction of the fabric. The tension is released by heat from the washer, dryer, steam and even sunlight, which causes the fabric to be reduced to its natural size.
This is not true for all cottons, as some shrink more than others and some shrink in hot water and not in cold.
I think years ago, fabric shrunk much more than it does today. And the selvage shrinks more that the rest. There are all kinds of reasons for shrinkage. I usually don't worry much about it and only pre-shrink my flannels.