1) What headache means, according to medical science: "Headaches in pregnancy 2nd trimester" Literally, headache implies a feeling of pain or discomfort lying partly or wholly in the head. Primary headaches are discomforts caused directly by overactivity or on account of problems with the structures in the head that are pain sensitive. This includes the blood vessels, muscles, and nerves...

 1) An overview Migraine means pain/ discomfort felt partly or wholly in the head. Primary headaches are discomforts lying in the head that are caused directly by the overactivity or the structural problems in the head. Which are pain sensitive. These include the blood vessels, muscles, nerves in the head and the neck. They may also result from changes in chemical activi...