TORONTO - Canadian actor-filmmaker Sarah Polley is pregnant.

A publicist for Polley's new film "Take This Waltz," which debuts at the Toronto International Festival this weekend, says Polley is 3 1/2 months along but hasn't revealed the baby's sex yet.

She's expecting a child with David Sandomierski, whom she married two weeks ago north of Toronto.

A graduate of law school, Sandomierski has clerked with Supreme Court chief justice Beverley McLachlin and is now doing his PhD in law.

Polley directed and penned the screenplay for "Take This Waltz," which stars Michelle Williams as Margot, a writer who is married to a cook (Seth Rogen) but attracted to her neighbour (Luke Kirby).

Sarah Silverman co-stars as Margot's sister in-law.

The film was largely shot in Toronto, where Polley was born.

"Take This Waltz" is Polley's first full-length directorial effort since 2006's "Away From Her," for which she won a Genie Award for best direction and got an Oscar nomination for best adapted screenplay.