She was assessed by obstetric and general surgical teams but they couldn't find the cause of the pain.
In the report, the woman said a doctor quickly examined her abdomen by pushing down on it, causing significant pain that she could barely breathe between sobs, and then left the room.
"He did not tell me what he was thinking, what the plan was, what he thought was wrong with me … I was then left in agony for another two hours without any further vital signs being completed despite [RM F] checking on me regularly."
The doctor said, in the report, that the clinical picture at that point in time was unclear, and the blood results did not demonstrate the likelihood of an inflammatory intra-abdominal cause.
The woman collapsed 17 hours later and was found to have a ruptured uterus.
Her baby initially survived but died a month later as a result of birth hypoxia - a condition where a baby's brain and other organs don't get enough oxygen and nutrients before, during or right after birth.
"This whole experience has left me completely emotionally and physically drained and distrustful of the medical profession," the grieving mum said.
The report stressed the rupture of an unscarred uterus in a non-labouring woman was extremely rare - occurring in close to 1 of 100,000 births - and difficult to detect.
One doctor said in the report they had only seen one other case in their 34 years of medical practice.
Deputy Health and Disability Commissioner Rose Wall accepted the rarity of the woman's condition and acknowledged "aspects of the woman's care were well managed" but she criticised the DHB for "missed opportunities for increased senior oversight" and "inadequate documentation" of some reviews.
"[There was] a lack of effective communication and co-ordination between the obstetrics and general surgery teams contributed to a delay in appropriate radiological assessment," Wall said.
In the report, the deputy commissioner said the DHB should also apologise to the woman and her family.
The clinical director of obstetrics - who was not named - said in the report: "I would like to send my sincere condolences to [Mrs C] and her partner for the loss of [Baby C] and for the traumatic events that they experienced during their time at [the public hospital."
Wall advised the DHB to provide evidence of recent staff training on co-ordination of care, escalation of care, and documentation.
Wall also suggested they use this case as a basis for staff training and report back on its implementation of the New Zealand National Maternity Early Warning System (Mews).
