They do tell you about the migraine but it's "less than <1% and temporary". My wife had an epidural. The first time was okayish but she got migraines. The second time they had a student do them. He was an incompetent ass. His instructor was even more incompetent and very very rude. They fucked it up. She had spinal pain for DAYS but thankfully (hopefully) recovered now. I told her no epidural for the next one I'll pay for a midwife or whatever not going through this again.