Dry labor is child labor in which there is a deficiency of the liquor amnii, or in which there has been a premature rupture of the amniotic sac.

Liquor amnii is the fluid that surrounds the developing fetus within the amniotic sac. This environment cushions the baby from injury and plays an important role in fetal development.

The amniotic sac encloses the embryo of the fetus, that provides a fluid environment to prevent dehydration during development of land based animals.