Do headaches occur around periods? What is menstrual migraine?

Menstrually-related migraine without aura is a migraine headache without aura in a menstruating woman that can start as early as two days before first day of menstrual flow and up to two days after the first day of flow in at least two out of three menstrual cycles. These headache attacks can occur at other times of the menstrual cycle as well.

Less common is pure menstrual migraine without aura which is a migraine headache without aura in a menstruating woman that occurs exclusively during the time window of two days before first day of menstrual flow and up to two days after the first day of flow in at least two out of three menstrual cycles. The headache attacks do not occur at other times of the menstrual cycle. 

The reason for distinguishing between menstrually-related migraine without aura and pure menstrual migraine without aura is that hormone prophylaxis is more likely to be effective for the latter.