Showbiz
Richard Young / Rex Features
The actress, who quit BBC drama Hotel Babylon last year, is three months pregnant with the couple's first child.
A friend said: "They are over the moon, it's exactly what they've been hoping for."
Outhwaite, 27, has spoken of her wish to be a mum since tying the knot with Ellis in 2006.
She said: "I don't want to leave it too late, especially as we would like to have more than one child."
She hinted that she would even consider quitting acting to start a family, saying: "My career and ambitions have been fulfilled, and I would be quite happy not to work again and look after the children. I don't really have that burning ambition any more."
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