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According to the Mayo Clinic these are some known causes of leg cramps. As you can see alcoholism and dehydration are listed. I doubt that a couple of glasses of wine will cause them, but drinking water right before going to bed may help.
Leg cramps can be caused by many conditions, ranging simply from dehydration to something much more serious such as kidney disease. Cramps often result from vigorous exercise, trauma to the muscle, or keeping the leg in an awkward position for too long, such as sitting in a crowded theater. Other causes can include medications such as birth control, diuretics (which are often prescribed for people with high blood pressure) and steroids.