The -Kill Bill- star - who already has daughter Maya, 13, and son Levon, 10, from her previous marriage to Ethan Hawke - is apparently pregnant with a daughter.
A source said: "Uma is having a babygirl," while a second added to Life & Style magazine: "She`s happy and just a few months along right now. She`s due in late summer."
The child will be the first for the 41-year-old actress and her businessman boyfriend Arpad Busson - who also has two children, Arpad Flynn Alexander Busson and Aurelius Cy Andrea Busson from a previous marriage to supermodel Elle Macpherson.
Uma and Arpad first got together in 2007 but later split in November 2009. Reports of a reunion circulated after they were spotted together at a Marc Jacob`s fashion show in Paris last year, and Uma recently gushed that she has finally found a "happy" place.
She told Harpers Bazaar magazine: "I have something I would really like to express about my love life. I`m happier with it now than I`ve been in many, many years. Yes I`m trying to have as peaceful a personal life as possible."