Anna Paquin and her husband Stephen Moyer are expecting their first child together.

The couple appear alongside each other in American vampire drama True Blood as lovers Bill Compton and Sookie Stackhouse.

Entertainment Weekly reports that Anna is pregnant and will deliver her baby this fall.

Stephen who has two kids from previous relationships has spoken previously about his desire to expand his brood with Anna.

"We're very busy at the moment but it will happen at some point," he is quoted as saying.

The stars, who reside in Los Angeles, reportedly bought a house soon after they married and were keen to ensure the property they chose was suitable as a family home.

Stephen, 42, and Anna, 29, began dating in 2007 after they met on the True Blood set. They got engaged in 2009 and married a year later in a romantic Malibu ceremony.

True Blood returns for its fifth season in June.