Diagnosing migraine.

Migraine is a common headache disorder, particularly in women. It usually starts during the teens and twenties, a time when many women are seeking contraception advice. Migraine without aura is the most prevalent type of migraine, affecting up to 70% of people with migraine, while the remainder experience attacks with and/or without aura. Aura is a phase of focal neurological symptoms, typically visual. An increasing body of evidence identifies aura as a marker of increased risk of ischaemic stroke and its presence is a contraindication to the use of combined hormonal contraception (CHC). However, aura is often confused with more generalised premonitory visual symptoms of migraine that may precede attacks of migraine with and without aura, which are not associated with stroke risk. Diagnostic confidence is needed so that CHC is not withheld unnecessarily.