THE idea of a TV series based on the problems of midwives in a rundown London area in the 1950s and ‘60s hardly sounds like the formula for a hit.

Yet, Call the Midwife – the BBC1 period drama that has just started its sixth series – is a huge success by any yardstick.

It’s set in Poplar and centres on Nonnatus House, a nursing convent and part of an Anglican religious order. Originally created by Heidi Thomas, it is based on the memoirs of Jennifer Worth who was a midwife in this area at the time.

The series is well-researched and generally agreed to be spot-on about life in this poor area during this period. Post-war, families struggled to survive here, housing conditions were often bad and people’s health affected.

To the programme’s credit, it has shirked none of the issues of the time including infant mortality, domestic violence, racial harassment and poor social conditions.

It is enduringly entertaining and absorbing and it’s now hard to imagine Sunday evenings without it.