Call the Midwife creator Heidi Thomas has revealed she doesn't know how long the show will go on for.
The writer spoke to HELLO! and other press at the launch of series 14 in November and revealed that while she doesn't know how long the drama will continue, she isn't "going to run out of stories".
"I get emotional standing here talking to you every year because time changes, time moves on, we move on," said the 62-year-old. We're 14 years into this and I still don't quite know how we keep going."
She went on to say: "People are always saying to me that Call the Midwife is something that is going to end very soon because the pill has arrived, so fewer babies will be born and that hasn't happened because for every woman who takes the pill, there is one who forgets or there is one that doesn't know it exists.
"Time and time again, I've been genuinely shocked by the extent to which society and women will create obstacles for themselves even though society is giving them every opportunity to do otherwise. It's in the fragility of human life that these stories exist," explained the writer, who is married to Dr Turner actor Stephen McGann.
"I don't know how long we're going to go on, we aren't going to run out of stories," she said. "People ask me every year, 'Where do you get your stories from?' and the simple answer is, I go to the British newspaper archive or I go into the medical archive.
"I think we are rooted in realism, love and changing times and because times keep changing, we will keep going on," she added.
Fans will be pleased to know that Call the Midwife will be on air until at least 2026 as the show was renewed for seasons 14 and 15 in February last year.
At the time, Heidi said in a statement: "We are a family behind the scenes, on the screen, and in front of the telly, and I'm thrilled that we're all heading into the 1970s together."
The popular period drama, which first began in 2012, chronicles the lives of nurses and midwives working at Nonnatus House in London's East End and is loosely based on the best-selling memoirs of Jennifer Worth. The series begins in the late 1950s and follows the residents of Poplar into the early 1970s, which is when the latest series is set.
A wide variety of stars have featured on the show over the years, including Miranda Hart, Miriam Margolyes, Helen George and Jenny Agutter.