igraine headaches is defined as a paroxysmal ailment, accompanied by a severe headache, generally on one side of the head, and associated with disorders of the digestion, the liver, and the vision. Menstrual migraine usually occurs when a person is under great mental tension or has suddenly got over that state.

Sixty per cent of all women with migraine have attacks around the time of menstruation. In approximately 14%, attacks are experienced only during menstruation. These can be very disabling.

Compared with other times in the menstrual cycle, a menstrual migraine is more than twice as likely to occur during the first 3 days of menstruation and more than three times as likely to be severe.

Menstrual migraine is defined as 'attacks occurring consistently from three days before to five days after the onset of menses'. Menstrual migraine is triggered by a drop in the level of the hormone oestrogen, which occurs around menses.

Studies have shown that supplemental estrogen given at the time of the natural monthly decline in these hormones delays the onset of mestrual migraine until the estrogen level finally decreases.

However, many other factors can trigger menstrual migraines including certain foods and environmental influences such as loud noises, glaring lights and changes in the weather.

Preventative treatment for menstrual migraine can include avoiding known triggers or taking preventative medications, for example antidepressants, anticonvulsans, beta-blockers, calcium channel blockers and anti-inflammatory drugs that reduce the production of the chemical signals prostaglandins which can trigger migraines in some patients.

A new menstrual migraine preventative treatment currently being investigated are estrogen patches worn during menstruation to prevent oestrogen levels from dropping and get menstrual migraine.