The experts say "no". It doesn't harm the chicks in the eggs. I personally pull my chicks as they get active and put them in the brooder. (As long as you have adequate humidty,) you should do what's most comfotable for you. Many leave the chicks till the hatch is over and have good hatch rates.well the other eggs have not started pipping yet but the chick that just hatched this morning has knocked the eggs all over the incubator -will that be a problem for the chicks trying to pip? (being that the eggs have turned and are no longer facing the same direction they were when they positioned themselves to hatch)