The `Celebrity Big Brother` star - who already has sons, Rocky, five, and two-year-old Striker, with husband Tom Williams - is six weeks along but admits the pregnancy wasn`t planned and thought she couldn`t have any more children because she had suffered from eating disorders in the past.
She revealed: "I`m so shocked but very pleased. To be honest, because of how ill I`ve been with my eating disorder, my periods had stopped and I thought I`d blown any chance of having any more kids so I was pretty devastated, because I want a house full. But suddenly my periods started coming back, which meant I was getting better.
"But the baby definitely wasn`t planned, I have the coil! I know that no contraception is 100 per cent, you just hope it is, or hope it doesn`t in my case - I feel very lucky."
Nicola says she would the baby to be a girl although would be happy if she had another boy.
The British beauty said: "I`d love a girl but I`d also be happy with a boy because I love going to the football, but I would love all the ballet and tutus too! I love children, I love being a mum and having a big family."