Migraine headaches are caused by abnormal brain activity, which can be triggered by various factors. These factors include:

• Genetics and environmental factors : Migraines seem to be caused by a combination of genetic, environmental, and lifestyle factors. They may run in families, and women are more likely to have migraines than men

• Hormonal changes : Fluctuations in estrogen, such as before or during menstrual periods, pregnancy, and menopause, seem to trigger headaches in many women. Hormonal medications, such as oral contraceptives, can also worsen migraines

• Triggers : Migraine triggers can include certain foods, drinks (especially alcohol and caffeine), stress, sensory stimulation such as bright lights or strong smells, sleep changes, weather changes, and skipping meals

• Neurological factors : Changes in the brainstem and its interactions with the trigeminal nerve, as well as imbalances in brain chemicals such as serotonin and calcitonin gene-related peptide (CGRP), might be involved in the development of migraines

The exact chain of events that leads to a migraine attack remains unclear, and the causes of migraines are still not fully understood. It's a complex condition that varies from person to person, and further research is ongoing to better understand its underlying mechanisms