The former "Dawson's Creek" beauty reportedly was seen at a pre-natal yoga class, World Entertainment News Network reported Monday.
The Daily Telegraph of Sydney says Williams regularly attends a weeknight yoga class that tutors pregnant women in their second and third trimesters. The paper also reports that whenever Williams is in public she always wears loose-fitting clothes.
Ledger, 25, and Williams, 24, started dating last June after meeting on the set of Ang Lee 's cowboy film "Brokeback Mountain," and Williams has been staying in Ledger's beachside Sydney home since December.
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