She will still be able to release the egg or tissue, but the swollen tissue of the prolapse does make it a little more difficult. Prolapse is one of the most urgent crises a hen can face. If the egg is intact and overlarge, it can lodge in the cloaca. This is often a death warrant as it cuts off the poop.
This condition also blocks the ceca which supply fluids to all of the body tissues, and prolonging this condition results in dehydration which can put strain on the heart. Along with dehydration, if calcium were not given, it increases the risk of heart attack.