Most of us are familiar with the German term Götterdämmerung, which translates as 'Twilight of the Gods' or more correctly as 'Gods' Twilight'. Another concept is Dämmerschlaf or 'Twilight Sleep', which became popular in the beginning of the twentieth century.
The treatment of choice for childbirth pains during the latter half of the 1800s was chloroform. The anaesthetic qualities of chloroform were first described in 1842. On November 4th, 1847, the Scottish doctor James Young Simpson first used the anesthetic qualities of chloroform on a pair of friends at a dinner party. This was done purely as entertainment rather than being a medical procedure.
The search was on for a safer means of sedation.
Twilight sleep was developed in Germany around 1900. It is an amnesic condition characterized by insensitivity to pain without loss of consciousness, induced by an injection of morphine (from opium) and scopolamine (from the deadly nightshade) in order to relieve the pain of childbirth. This combination, which mimics the Greek nepenthe, induces a semi-narcotic state which produces the experience of childbirth without pain. However, some scientists state that women do feel the – sometimes - excruciating pain, but the drug removes all memory of that pain.
Pain can lead to all sorts of long-term traumatic effects, such as a postpartum depression. In the end it doesn't really matter if a woman does not feel the pain or simply does not remember the pain she had experienced.
The combination of morphine and scopolamine entered mainstream medical use around 1907, but it also had its drawbacks. In the end the drug was discontinued because it also had depressive effects on the central nervous system of the infant. This resulted in a drowsy newborn with poor breathing capacity.
 Marx: Historische Entwicklung der Geburtsanästhesie in Anaesthesist - 1987