The `Mad Men` actress - whose relationship with `Saturday Night Live` star Jason Sudeikis ended in January after around: six months of dating - is due to give birth to her first child in the autumn, though she has not disclosed who the father of her baby is.
Her spokesperson said: "JanuaryJones is happy to announce that she is expecting her first child this fall."
A friend of the star insisted she is not worried about raising the child alone.
The source told People.com: "She`s really looking forward to this new chapter in her life as a single mum."
The 33-year-old beauty - who plays glamorous mother-of-three Betty Draper in the hit TV series - has previously been romantically linked with Ashton Kutcher, Adrien Brody and singer Josh Groban.
January recently revealed she is happy being single because she doesn`t like living with other people.
She said: "I don`t like living with other people. I don`t mind being alone. I just don`t really have a lot of time or energy to put into a relationship when nothing`s going to happen.
"Everybody writes that they think I`m so unhappy. I`m [just] in my own head. I`m doing things. Keeping things interesting.
"I don`t like having an entourage of people around me. I have a select group of friends who I hang out with."