January Jones gave birth to a baby boy named Xander Dane Jones on Tuesday, her rep tells Us Weekly.
"Mom and baby are doing great," the rep says.
It's the first child for the Emmy-nominated Mad Men actress, 33.
Jones announced her pregnancy in April. The star -- who dated Saturday Night Live's Jason Sudeiki, singer Josh Groban and Ashton Kutcher in the past - has not yet disclosed the identity of Xander's father.
Back in June, Mad Men creator Matthew Weiner said the actress had been wanting a baby "very badly."
"She's got a big heart and she's been talking about having children since I met her, which is not always common with actresses," Weiner said. "I think she's going to be amazing."
Although she remained tight-lipped about her child's father, Jones admitted that she was enjoying her pregnancy.
"I've been in a nesting phase just preparing my house and stuff," the L.A. denizen said.