The actress, who recently admitted that she fears ageism in the TV industry, has spoken repeatedly in media interviews about how she will turn 50 this month.
However, Redman's birth certificate has now allegedly been uncovered by The Mail On Sunday. The document indicates that she was born on August 12, 1957, which would make her 51 already.
Discussing her age in one interview last month, the star commented: "I certainly haven't booked an appointment for a facelift for my 50th. But perhaps, in five years' time, if I feel that it's all going south and I'm not getting the work, I might consider a tweak or two."
In another article last November, she said: "I really do not want to turn 50. It's horrible. I know it's only a number but I think it's the association of turning 50 with women being past it."
A spokeswoman for Redman would not comment on the discrepancy.