A month before "Call the Midwife" returns on air for its fifth season, BBC has already announced that the British period drama will return for a sixth season.

BBC Director-General Tony Hall made the announcement during his surprise appearance at the launch event of "Call the Midwife" season 5 in London.

Neal Street Productions executive producer Pippa Harris reacted to BBC's announcement, saying:

"I am delighted that the BBC has decided to commission Series 6 of 'Call the Midwife' even before we have gone on air with Series 5! It really demonstrates their commitment to and passion for the show. The ongoing success of 'Call the Midwife' is down to the incredible writing skills of Heidi Thomas and the talent and dedication of our wonderful cast and crew. I hope the audience will enjoy watching Series 5 which I firmly believe is our strongest yet."

While the plot for "Call the Midwife" season 5 is yet to be disclosed, the series is expected to discuss the accuracy of medical practice during the 1950s to 1960s.

The previous seasons tackled other important women's health issues like still births and the National Health Service as well as other social issues like teenage pregnancy, poverty, and raising kids with deaf mothers.

Thomas expressed her thoughts (via The Guardian) regarding the way BBC accepted the show's controversial theme. "No other channel would make this show, have encouraged us to be so diverse, urged us to be so ambitious, allowed us to be so bold. In the middle of the cake, the nuns, we tell some quite hard stories. In series five we go brave," Thomas explained.

However, Miranda Hart is not expected to reprise her role as Chummy on "Call the Midwife" season 5 since the actress is working on other projects at the moment.

"Call the Midwife" season 5 will premiere in early 2016, which means that the sixth season will be aired sometime in 2017.