The `Coronation Street` actress and her `Hollyoaks` hunk fiance Jamie Lomas welcomed their first daughter, Polly Lomas, into the world five weeks early on 23.03.11 at the Manchester Royal Infirmary, and both mother and baby are said to be "doing well".
In a statement to website MailOnline, Kym`s publicist said: "Jamie Lomas and Kym Marsh are delighted to announce that they are the proud parents of a babygirl, Polly Lomas.
"Polly was born on Wednesday evening weighing 4lbs 1oz. Mum and baby are doing well."
The 34-year-old star - who went on early maternity leave from the ITV1 soap in January after doctors advised her to take a break from her `Coronation Street` commitments - recently admitted she has been "very down" throughout her pregnancy.
She said: "It`s not been enjoyable at all. From 28 weeks I`ve been able to breathe a little bit. Yeah, there have been times I`ve been very down."
Kym - who has two children David, 15, and 13-year-old Emily from a previous relationship - and Jamie tragically lost their first child Archie in 2009 shortly after he was born 18 weeks early.