These are very hard choices, There is good info on this site about helping Chicks, just keep in mind this is the time he/she absorbs the yolk. I helped a chick after 28 hours and she was fine. Maybe place a warm paper towel in there for humidity.
When should I intervene with a hatch? I'm afraid the membrane may be too dry. - Page 2
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If it was me, I'd add a damp sponge near the eggs and wait until morning. Do you have other pips?
I had a couple get stuck.. a very rare event as I hatch out about 100 a year every year and its only happened 2 times.
First time I waited too late.. and the chick had died in the membrane.
Second time I helped when I saw the rest of the chicks had hatched and had dried off and were running about... and I saw the one stuck in the egg still had not made the hole any bigger.
I moistened the membrane with a damp warm cloth.. and waited a few more hours.. still no more progress.
I decided it was going to die if I left it.. so I had nothing to loose helping.
I wet the egg and membrane again.. gently peeled off the shell in little bits.. then peeled open the membrane to get the chick out.
Do this really slowly and keep the chick warm. Don't teat any veins or pull too hard.. being really careful at the area of the chicks belly button.
I got the chick out... it was very weak and not moving. I put it back under the broody hen as it was night time.. in the morning I went to see.. expecting it to be dead... but it was dried out and happy.. and it was HUGE.. compared to the other chicks.. even through it came out of the same sized egg as the others. .... I think that was the problem.
Might not be the recommended way to go about it but we'll see what happens.