A new mother killed herself in a hospital room after staff ignored her husband's plea that she should be put on a 24-hour watch.
Adam Mager, 39, is planning legal action following the death of his wife Diana, who was being treated at Green Parks House psychiatric unit in Orpington, Kent, after suffering a severe form of post-natal depression after giving birth to Sofia in November 2011.
Mrs Mager, who was self-harming and battling chronic anxiety, was admitted in June 2012 but committed suicide in August, at a time when she was being checked every 15 minutes.
She killed herself when she was alone. Earlier on in her stay she had been allowed out on occasions for an hour at a time - but had once tried to jump off the Tate Modern building in central London.
Now Mr Mager is to sue Oxleas NHS Foundation Trust, which runs the hospital, reported the London Evening Standard.
Mr Mager, who also claimed that his wife once smuggled a kitchen knife into the hospital unit, said: "Diana was overjoyed at becoming a mother - it was all she ever wanted.
"I believe she would be alive today if she had received the proper care she desperately needed. Instead, I have to explain to our daughter why her mother is no longer with us."
The death of Mrs Mager, who had a history of depression, is being outlined in an inquest which was opened yesterday. It will also highlight a lack of specialist care for post-natal depression.
Mr Mager's lawyer, Mark Bowman of Field Fisher Waterhouse, based in Aldgate, east London, said his client was 'concerned that more could and should have been done to help her'.
Trust chief executive Stephen Firn said in a statement: "I was deeply saddened by Mrs Mager's death and would like to express my sincere condolences to her husband and family.
"We carried out a full and thorough investigation which concluded that it could not have been predicted or prevented."
The trust said it could not comment further while the inquest is ongoing at South London Coroner's Court in Croydon. It is being held by Coroner Dr Roy Palmer and is expected to finish next Monday.
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