A new study looking at a large series of patients who had a lumbar puncture (a test to collect fluid from around the sooner often used to get more information about inflammation and other problems going in the brain our nerves) found some factors that made a headache more likely after the procedure.
Taking more fluid and doing the procedure sitting was associated with more headache early on, within the first twenty four hours, but this did not mean more headaches that needed treatment after a week. Overall only 4% of patients needed that intervention, called a blood patch.
JAMA Neurol. 2015 Mar;72(3):325-32. doi: 10.1001/jamaneurol