The actress, who has played barmaid Alicia Gallagher in the ITV1 soap since August 2010, told Hello magazine that she and husband James Shepherd were "so happy" to discover that they would become parents in August.
"We've not been going to many functions and I've been disguising it quite a lot," Anderson said, explaining that her bump would be hidden on screen before she goes on maternity leave.
"I think there'll be a lot of standing around the bar and carrying huge handbags," she joked.
While recalling her first scan, Anderson admitted that the couple will find out the sex of their unborn child at the follow-up, saying: 'I cried and James had a tear in his eye. It was incredible to see the tiny hands and feet, the face and this little thing dancing away.
"We want to know who we're talking to, so we can have nice little conversations."
Speaking about her late grandfather, who died last year, the West End star - nominated for 'Sexiest Female' at the British Soap Awards - said that he had been an inspiration to her.
"If I'm feeling nervous about the baby, anxious that things will be all right, I feel him around me," Anderson added. "It's a lovely feeling, as though I have someone watching over me."
Read the full interview in the new edition of Hello, out now.
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