Less than a month after news broke that former "That '70s Show" co-stars Mila Kunis and Ashton Kutcher are engaged, sources are confirming the actress is pregnant with the couples' first child.

E!, which broke the news Sunday, reports Kunis, 30, was recently spotted attending a prenatal yoga class in Hollywood, and that she and Kutcher, 36, will welcome a baby later this year.

A friend of the couple tells People "it's still early," but that they are "both very, very happy."

Sources speaking to both E! and People say reports last week that the couple is expecting twins are not true. Though neither Kunis nor Kutcher have confirmed nor denied their engagement (or pregnancy), the "Ted" star stepped out Feb. 27 in Los Angeles wearing a sizable sparkler. The two met on the set of "That '70s Show" in 1998, and began dating in spring 2012 after Kutcher's split from now ex-wife Demi Moore.