The newborns who appear on the show are a mix of at least four different prosthetic babies, including a tiny premature baby, a full-term baby, a mixed-race baby, and anatomically correct baby with interchangeable parts. However most shots are filmed with real babies who are around a week old.
Long before Jennifer Worth's memoirs were filmed, she spotted Miranda Hart and knew that she would be perfect to play Camilla "Chummy" Fortescue-Cholmeley-Browne, the six-foot-one, ungainly, clumsy midwife who features in her books. Hart, who also hails from an aristocratic background like her character, agreed to take the role of Chummy if the books were ever filmed.
The midwives are based in Nonnatus House, which is named after St. Raymond Nonnatus (nonnatus being the Latin for "not born") who was born by Caesarean section, and is the patron saint of pregnant women and childbirth.
The series is based on the best-selling memoir of the same name by Jennifer Worth, the first in a trilogy of books describing her work as a district nurse and midwife in the East End of London during the 1950s. The premiere episode was dedicated to Worth's memory, as she died six months before it aired.