Casey Anthony: I Got Pregnant with Caylee After I Was Raped

Casey Anthony said she was raped at a party when she was 18 and that's how she conceived Caylee -- this according to Casey's former psychiatrist

The psychiatrist -- Dr. Jeff Danziger -- recounts the allegation in his deposition, which was just unsealed today by a Florida judge.

In the deposition, Danziger cites an interview he had with Casey in November 2010 -- claiming, "Two beers, possibly given another drug. Woke up passed out ... Don't remember anything at a party, age 18. This is how she said she got pregnant."

Danziger claims Casey did not know the identity of the father.