Michelle Rounds and Rosie O'Donnell (WENN.COM)

Comedian Rosie O'Donnell's fiancee Michelle Rounds is trying for a baby just weeks after they announced their engagement.

The couple has been dating since last summer and they unveiled plans to marry shortly before Christmas.

O'Donnell, who has four children from her marriage to Kelli Carpenter, has now revealed she is hoping to expand her family with Rounds.

During an episode of her American talk show Rosie, the star interviewed celebrity medic Dr. Mehmet Oz and told him Rounds is currently "trying to get pregnant".

A source tells Usmagazine.com, "Michelle is seeing a fertility doctor. She is really excited and they cannot wait to add to their family. Rosie goes to all of her doctors' appointments with her and is really supportive. She isn't pregnant yet but they hope as soon as possible she will be."