But since the BBC drama began back in 2012, it has seen plenty of stars come and go over the years. More recently, a fan-favourite character has been revealed to be leaving the show which will no doubt surprise fans.
HELLO!'s taking a look back at the stars who have walked away from heartwarming midwifery drama over its thirteen seasons.
This week, it was reported that Olly Rix, who plays Matthew Aylward, has left the show but the reasons why have not been shared; neither the actor nor the BBC have spoken out on the news. HELLO! has reached out to the actor's representatives and the BBC for comment.
The news of the actor's exit might be surprising to fans after Olly's on-screen persona, Matthew, featured heavily in the season 12 finale when he married Nurse Trixie Franklin, played by Helen George.
Leonie, who was adored for her role as Lucille Anderson, told fans in a statement on social media in February that she would not be back for the new series. The actress did not reveal the reasons behind her decision to leave the show, but the star did state in her announcement that she was moving on to new projects.
She told fans in part: "Thank you all for embracing Lucille and rocking with me on this journey, it is with a heart full of love and appreciation that I embark on pastures new."
Jessica Raine starred as Nurse Jenny in series one to three, eventually leaving in 2014. According to reports, Jessica left the show in order to pursue film work in the United States. Since leaving Call the Midwife, the actress has gone on to star in shows like Line of Duty, Partners in Crime, The Last Post and Baptiste.
Bryony Hannah was in the BBC drama from 2012 to 2017, playing the role of Nurse Cynthia Miller. In 2017, it was announced that the actress, alongside three others, wouldn't be filming for season seven.
Bryony left the show to concentrate on other work, and went on to focus on her theatre career. Bryony was even nominated for the prestigious Olivier Award for Best Performance in a Supporting Role for the play The Children's Hour.
Emerald Fennell has had a hugely successful career. Alongside her role in Call the Midwife as nurse Patience Mount, which she in left 2017, she has stared in shows like New Tricks, Victoria and The Crown. Emerald left Call the Midwife in 2017 to focus on her writing work for season two of Killing Eve starring Jodie Comer. Her work with the pen earned her two primetime Emmy nominations. She also received Oscar nominations for her film, Promising Young Woman.
The following year, Emerald debuted her role as the Duchess of Cornwall in The Crown season three. Emerald said of her departure from Call the Midwife: "Very sad I'm not filming wonderful CTM, had writing to do and they were so lovely and gave me the time to do it because they are the best."
Kate Lamb played Nurse Delia Busby in the drama who had a relationship with Emerald Fennell's character. According to reports, Kate left the show to take a break from acting to focus on her other interests and also works as a professional dog trainer.
Jennifer Kirby joined the show in series six as Nurse Valerie Dyer. In August 2020, it was announced that she was leaving the show and would not be returning after four years, instead focusing on other acting work. Announcing the news, She wrote on Twitter: "After four joyful years spent with Call the Midwife I have decided to say goodbye to Nonnatus, Val, and the wonderful cast, crew and production team.
"The programme is truly a national treasure, and it will always be a huge honour for me to have been a part of something so wonderful. I can't wait to keep watching our beloved Nonnatuns from the other side of the screen. Long live Call the Midwife. So long chicks."
Actress and comedian Miranda Hart played Matron Camilla Fortescue-Cholmondeley-Browne from 2012 until 2015 when she left to focus on film work. Soon after, the actress then appeared in the film Spy, and Jane Austen adaptation, Emma, alongside Anna Taylor-Joy and Bill Nighy.
Ben Caplan played Peter the policeman from 2012 to 2017, before announcing he was leaving to pursue more diverse roles. At the time he said: "I'm taking a break to concentrate on other things. But the door is very much open for both myself and Miranda and I'm sure we'll make an appearance again. It's been lovely to have been there since the beginning, an amazing roller coaster ride, and I’m honoured to have been part of the whole journey, but there comes a point six years down the line that, as an actor, it's good to keep my foot in with the theatre world and exploring other roles."
Pam Ferris has appeared in plenty of well-known shows and films over the years including Matilda, Harry Potter and more. In 2012, she joined the cast of Call the Midwife as Sister Evangelina, before leaving the show due to logistical reasons.
Speaking to The Mirror on her departure, Pam said she's "very, very selective" about what jobs she accepts. "There's not much real quality work being done. Television has speeded up so much that it's very hard," she said.