People magazine reported Saturday that, according to court papers, the 40-year-old actress cited "irreconcilable differences" when filing for divorce from the German millionaire last month.

A source said Giersch has also filed papers for a legal separation from the actress, who is 3 months pregnant.

The couple already has a 2-year-old son Hermes, People said.

Rutherford, who plays Lily van der Woodsen on the CW teen drama, is expected in New York Tuesday to take part in "Gossip" filming.