Abortion has previously proved controversial for the show after a 'backstreet' termination was screened pre-watershed in 2013 during the drama's second season. The scene resulted in viewers complaining to Ofcom.

Dame Pippa told The Sunday Telegraph the drama had a responsibility topic to cover the topic as it remained an "emotive" subject across Britain, including Northern Ireland where abortion remains illegal.

She said: "Many of the reasons people enjoy the show is because things have improved so drastically since the Sixties but I think it is useful to remind people of where we have come from.

“With the abortion debate we have seen recently in Ireland, still such an emotive live topic, it’s useful for people to remember that it wasn't that long ago that it wasn’t legal in the rest of the UK, and indeed is still illegal in Northern Ireland.

“It is a responsibility to make sure we are covering things sensitively in a properly researched way.

“I hope it will make people stop and think and remember how recently abortion was illegal here, and the devastating effect that that had on a huge number of women's lives, not just the women themselves but the people closest to them.

“It's a hugely important issue.”

The latest series will also mark the introduction of cervical screening, which was introduced to England in 1964, with creators claiming to show the first dramatised smear test before the 9pm watershed.

Dame Pippa said: “I can't remember seeing a smear test depicted on a pre-watershed drama, that is the key.

“Clearly many factual programmes look at health issues in a very serious way, but Call The Midwife talks to such a broad audience and it also talks to a very young audience.”

Although the female-heavy team behind Call The Midwife pride themselves on detailing the social and medical developments of the period, the specifics of some procedures have previously courted controversy.

Complaints poured in to Ofcom and online forums in January 2013 after overworked mother Nora Harding, portrayed by Sharon Small, attempted to abort her pregnancy in a scene condemned by critics as “harrowing”.

However, stars of the show have argued that “ground-breaking” plot lines that tackle “really gritty stuff” help Call The Midwife surpass other period dramas in terms of quality.

The previous series ended with the death of Nurse Barbara Gilbert, played by Charlotte Ritchie, from sepsis which led to 5,000 calls to the BBC Action Line, some of which were specific enquiries about the disease.

“People looked in far greater depth at that illness than if it had been a smaller character who carried that storyline.

“That often happens depending on this issue that we cover, people want to find out more," added Dame Pippa.