Justin Bieber sure knows how to party. He partied so hardy that it seems like some people just couldn't keep up. The 19-year-old pop star had to call an ambulance to his home in Calabasas were he was hosting the massive blow out after a girl passed out and wouldn't wake up.

According to TMZ, a female guest passed out at Bieber's house in the early morning hours on Saturday, Dec. 14.  Us Weekly has confirmed that after Bieber called an ambulance to assist her she fully recovered. "There's no issue. A call was made out of an abundance of caution, but the woman was given some food and liquids, and she's fine and went home", a source to Us.

The gal, who is only 20 years old, just seemed to be having such a great time that she drank more than she could handle. The party was probably a swimming pool of liquor, even though Justin is still underage, and well she took full advantage of the festivities. The "All That Matters" star was very lucky to have gotten away with having alcohol at a party where not even the host was of the legal drinking age. If that would have been us back when our parents used to leave town and we would throw house parties, we would have been in trouble with the law and crucified by our parents.

TMZ reports that after the young lady regained consciousness she called off the ambulance, probably to avoid any problems for her and Bieber. At least it was nice to know that even though the "Boyfriend" singer knew what he could be risking he still called 911. Not that Bieber would let someone be at risk at his expense but the pop star doesn't always have the greatest judgment. The woman went home after waking up and the party went on. Party like a rock star, Biebs -- just don't get caught. Justin Bieber, what are we going to do with you?