Safety and simplicity of self-administered analgesia.
D000698:Analgesia; D000776:Anesthesiology / Q000295:instrumentation*; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D009609:Nitrous Oxide; D010146:Pain; D059408:Pain Management; D011247:Pregnancy; D014241:Trichloroethylene
D014241:Trichloroethylene; D009609:Nitrous Oxide
ANESTHESIOLOGY/apparatus and instruments; LABOR; NITROUS OXIDE; TRICHLOROETHYLENE