It used to be common practice not so long ago for some women to give birth during "twilight sleep" which was usually induced with the aid of drugs, it is an amnesic state and the births in such a state were called a "twilight birth".

Just some loosely related trivia. But you can literally give birth while being conscious is such a state and have no recollection of it or the pain of child birth. The practice is no longer widely used due to detrimental affects the drugs had on the baby.