Are any health risks incurred from drinking a glass of wine?

It isn't likely, though women are advised to avoid wine and other alcoholic drinks during pregnancy. Since 1990, every bottle of wine, beer, and spirits sold in the United States has carried the warning, "According to the Surgeon General, women should not drink alcoholic beverages during pregnancy because of the risk of birth defects."
 
Drinking excess amounts of any alcoholic beverage also can cause alcohol poisoning.
 
Consumers who are extremely allergic to sulfite are advised to avoid wine. All wines contain sulfite, a by-product of fermentation.
 
As a result of oxidation, wine can quickly convert to vinegar once it is opened. While the vinegar won't make you sick, it won't taste very good. Proper storage can delay the onset of oxidation.
 
Source(s):
Wines.com "Are There Any Sulfite-Free Wines?"
Wines.com "Can Leftover Wine Be Saved?"