title: An aid to identification of the subarachnoid space with a twenty-five gauge needle.
mesh_terms: D000767:Anesthesia, Epidural / Q000379:methods*; D005260:Female; D006261:Headache / Q000517:prevention & control*; D006801:Humans; D009339:Needles; D011247:Pregnancy; D013346:Subarachnoid Space