Migraine-associated nausea is an Important Target for Treatment
American Migraine Prevalence and Prevention (AMPP) Study”  showed:
“Among the 6488 respondents with episodic migraine, approximately half (49.5%) reported high-frequency nausea (i.e., ≥half the time) with headaches. High-frequency nausea was more common in females. Persons with high-frequency nausea, compared with the no/rare or less than half the time nausea groups, reported significantly more headache symptoms and more headache-related impact.
High-frequency migraine-associated nausea is common and is a marker for severe, debilitating migraine. Nausea makes an independent contribution to migraine-associated disability and impact. Management strategies that take nausea into account could reduce the burden of migraines. Nausea is an important target for monitoring and treatment.”
 Lipton RB, Buse DC, Saiers J, Fanning KM, Serrano D, Reed ML. Frequency and burden of headache-related nausea: results from the American Migraine Prevalence and Prevention (AMPP) study. Headache. 2013;53(1):93-103.