Causes. The exact cause of Cyclic Vomiting Syndrome remains unknown, but experts have come up with certain factors that could contribute to the disorder. These factors include dysfunction in the autonomic nervous system, hormone imbalances, and dysfunction in the central nervous system. Other conditions that stand as CVS triggers are stress, anxiety, depression, migraines, hot weather, menstrual periods and exercise. Certain diets and food intake strategies such as fasting, overeating, or eating before bedtime can contribute to CVS. Consuming chocolate, cheese, hot dog and foods rich in monosodium glutamate can also trigger CVS.