British actor Idris Elba's girlfriend, makeup artist Naiyana Garth, is pregnant with the couple's first child, UsMagazine.com said Friday. The baby's gender and anticipated due date were not reported. Elba already has a daughter, Isan, with his ex-wife Dormowa Sherma, the magazine said. Best known for his work on TV's "Luther" and "The Wire," the actor is generating Oscar buzz for his performance in "Mandela: Long Walk to Freedom."