CNN: Sleep specialist Rebecca Robbins, an instructor in the division of sleep medicine for Harvard Medical School, explains when to worry about snoring.

Snoring can be a key sign of obstructive sleep apnea, a serious sleep disorder in which people actually stop breathing for 10 seconds or more at a time. “When it’s loud, raucous snoring, or it’s interrupted by pauses in breathing, that’s where we start to get concerned,” Robbins said.

Being really tired during the day is a prime indicator of poor sleep. Combined with snoring, it can be a telltale symptom of sleep apnea.

“Daytime sleepiness is one of the strong predictors of sleep apnea,” Robbins said.”Falling asleep anytime you have a moment — sitting down for a break after lunch, in a movie theater — those are all hallmark symptoms along with fatigue and taking the house down with your snores,” said Robbins, who coauthored the book Sleep for Success! Everything You Must Know About Sleep But are Too Tired to Ask.

Get the full story at cnn.com.