Call the Midwife creator Heidi Thomas has opened up about the future of the beloved BBC period drama.
MORE: Call the Midwife teases heartbreaking storyline ahead for beloved character in series 12
In a new interview, the writer revealed that the show could run into the 1970s, although they don't know what plans the BBC has for the programme beyond seasons 12 and 13.
WATCH: Have you caught up on series 11?
"I think in principle, it could go into the 1970s," she said to RadioTimes.com before explaining that the order of the nuns on whom the Nonnatus House nuns are based stayed in East London until 1976.
"There are so many stories to tell, medically, socially, even emotionally, and I think we could keep on going," she continued. "The proviso I would give is that at the moment we're only commissioned for series 12, which we're halfway through filming, and series 13, which we will make next year.
"And beyond that we don't know what plans the BBC has, so yes we would be waiting on news from them I think."
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Season 12, which is currently being filmed, is set to introduce some interesting storylines and will even revisit characters from previous series.
The series could run into the 1970s
In the same interview, Heidi revealed that the show will delve back into the thalidomide tragedy, a storyline first introduced in season four. She said that the Mullucks family will return to screens in season 12, with Rhonda set to have another baby.
The 59-year-old creator explained that the new pregnancy "puts them under a certain amount of pressure and gives them a lot to worry about".
She added: "We haven't actually been with that family for five years, so we're picking up the pieces for them and it makes for a very special Christmas special."
Heidi teased some sadness ahead for Lucille
Fans can also expect some heartbreak for Nurse Lucille Anderson, played by Leonie Elliott. Teasing the upcoming series, Heidi dropped a hint that the beloved nurse will be grappling with some tough times ahead.
"Looking forward to Christmas and beyond Christmas, something rather wonderful happens to Trixie," she began, before adding: "Lucille has to contend with a reasonable amount of sadness, and what else can I say? We have a new nun coming to join the line-up, Sister Veronica."
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