“There’s a ten per cent chance that any woman will get post-natal depression,” Chris told the Daily Mail. “For someone who has suffered before — like Jo following the miscarriages — there’s a 50 pc chance of having it again, so that alone should have set off alarm bells for those monitoring her pregnancy.”
This link from the black dog institute says that previous pregnancy loss and depression increase the risk of PND- http://www.blackdoginstitute.org.au/...revioushistory
The article also said she had been referred to the mental health crisis team. I'm not sure how it works in the UK but here that doesn't happen unless you are considered to be approaching, or at, crisis point. I do think it's fair to assume she was suffering something, whether PND or another form of depression.
I agree that it would seem the medical professionals had the wrong focus, but as you said, perhaps she wasn't displaying symptoms. Perhaps she was only displaying moderate symptoms. We don't know. For all we know, they responded appropriately to the symptoms she displayed. Regardless, it's a tragedy.
I wonder if there was investigation into the hospital and other staff and what the outcome was?