title: A sequential study of intravenous analgesic treatment during labour.
mesh_terms: D000698:Analgesia; D000771:Anesthesia, Intravenous; D000773:Anesthesia, Obstetrical; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D007977:Levallorphan / Q000009:adverse effects; D008614:Meperidine / Q000009:adverse effects; D010423:Pentazocine / Q000009:adverse effects; D010919:Placebos; D011247:Pregnancy; D012965:Sodium Chloride / Q000009:adverse effects
chemical_list: D010919:Placebos; D007977:Levallorphan; D012965:Sodium Chloride; D008614:Meperidine; D010423:Pentazocine