For as long as I can remember, there have been Anglican nuns. Where my grandmother grew up, on the same road there existed two convents, one Catholic, the Sisters of Mercy, and another Anglican, an extension of the same order (the Sisters of St John the Divine) which the show “Call the Midwife” is based on.
The show is based on the diaries and recollections of Jennifer Worth, however it has been expanded to included new stuff from the BBC’s imagination, though the historical authenticity is on par.
She criticised a film called “Vera Drake” that portrayed the life of a working-class performer of illegal abortions, and said that they were far from quick and painful as what was shown in the movie but rather almost always fatal for the mother as well. I don’t know if she was pro-choice or pro-life, and that’s hardly our business anymore.
The show, being historically accurate, would portray the attitudes towards contraception just as it was. Keep in mind that a lot of people in the East End of London at that time lived in poverty, and may have been fallen away from the Anglican church, and might have seen contraception as a miracle (without consideration of the moral consequences). However, I highly doubt the nuns would have - the Anglican sisterhood being mainly a high Church operation.
About the incest and other things, I don’t think the show condoned it at all. It was what happened. You really did see that in those circumstances, and you kept quiet - you didn’t concern yourselves with the lives of others in such an intimate affair. It was common for siblings to live together if they were unmarried, and in my neck of the woods it still is. I think the show perhaps could have added a more condemning air to that particular episode but for what it’s worth, the facts stand.