Ashlee Simpson dodges pregnancy questions during TRL taping

Ashlee Simpson remained coy when asked questions about her rumored pregnancy during the taping of TRL in New York Tuesday.

A source at the MTV show says the 23-year-old -- who recently announced her engagement to boyfriend Pete Wentz -- dodged the pregnancy question, saying that if all the rumors about her were true, she "would have had a baby by now."

This was Simpson's first public appearance since announcing her engagement to the Fall Out Boy rocker. The show will air Thursday.

Just before performing her song "Little Miss Obsessive," Simpson took a question from a female fan, who asked the singer to show off her engagement ring. Simpson, who was sporting a sexy-black cardigan, white ruffled shirt and tight denim skirt, happily showed off her diamond eternity band.

Ashlee -- the younger sister of former reality TV star/singer/actress Jessica Simpson -- is busy promoting her new album Bittersweet World, due out April 22. She is also scheduled to perform on the Today show Friday.