The 35-year-old actress, who won a Tony Award in 2003 for playing Tracy Turnblad in Broadway's "Hairspray," strained to speak during the panel because she said she's beginning to lose her voice.
"I just talk too much," joked Winokur, who's partnered with professional dancer Tony Dovolani on the show.
Winokur and husband Judah Miller are expecting their first child. Winokur, who had cervical cancer seven years ago, said the baby is being carried by a surrogate mother and is due in four months.
Other participants in the Paley festival's "Dancing with the Star" panel were hosts Tom Bergeron and Samantha Harris; judges Len Goodman and Bruno Tonioli; professional dancers Cheryl Burke, Derek Hough and Julianne Hough; celebrities Cristian de la Fuente, Drew Lachey, Jane Seymour and Kristi Yamaguchi and executive producer Conrad Green.