Call The Midwife to continue post-memoirs

The plot follows newly qualified midwife Jenny Lee (Jessica Raine) and her colleagues coping with the medical problems in a deprived area of East London

Call The Midwife screenwriter Heidi Thomas has said the drama will continue after the second series, despite the memoirs it is based on running out.

Set in east London in the 1950s, Thomas has used a trilogy of accounts by the late midwife and writer Jennifer Worth.

Series two is currently being broadcast at 8pm GMT on Sunday nights on BBC 1.

But Thomas assures fans she received Worth's blessing to continue into series three: "Don't worry. It doesn't mean the show will end."

"The characters will be well developed by then and Jennifer was happy for us to continue," she told the Radio Times.

The final episode of series one attracted 9.2 million viewers, making it the most successful new drama on the channel since 2001.

The first series of Call the Midwife, adapted by Heidi Thomas, began transmission in January 2012

The first episode of its second series held its sizable audience and was watched by 9.3m.

As well as screenwriting, Thomas is executive producer of the programme.

She said that the hit TV show has prompted an emotional response from people, from crew to viewers and cameramen often "getting something in their eyes".

She told the magazine: "The edit suite has a wooden floor and was wet after we watched the Christmas special."

Thomas's credits include the TV adaptation of Elizabeth Gaskell's Cranford and the 2010 series of Upstairs Downstairs.

Her husband Stephen McGann stars in the show alongside Jessica Raine, Miranda Hart and Jenny Agutter.