Snoring is the often loud or harsh sound that can occur as you sleep. You snore when the flow of air as you breathe makes the tissues in the back of your throat vibrate. The sound most often occurs as you breathe in air, and can come through the nose, mouth or a combination of the two. It can occur during any stage of sleep. Snoring is more common in men, though many women snore. It appears to run in families and becomes more common as you get older. About 40 percent of adult men and 24 percent of adult women are habitual snorers. Men become less likely to snore after the age of 70.