In a tragedy that has highlighted the dangers of obesity for pregnant women and the need for specialist care, Kathryn Windmill's first baby Mabel died shortly after being delivered via an emergency caesarean at Latrobe Regional Hospital three years ago.

On Wednesday, Coroner Jacqui Hawkins said that although Mrs Windmill's body mass index of 48 meant she should have been transferred to a tertiary hospital for birth as per Latrobe's guidelines, she was instead cared for at Latrobe, where a locum obstetrician made "sub optimal" decisions during her labour.

Mabel died shortly after being born via an emergency caesarean at 5:57pm on October 10, 2012. This followed more than 13 hours of labour and a failed attempt to deliver the baby vaginally with a vacuum extractor. It also followed Mrs Windmill reporting concerns that she could not feel her baby moving much six days before the birth.

Coroner Hawkins said that when Dr Philip Watters, a locum obstetrician with more than 35 years' experience, took over the care of Mrs Windmill on the morning of October 12, he failed to appreciate the severity of abnormal signs coming from a monitor of her baby's heart beat, and the implications this had for the medical management of her labour.

While the evidence showed Dr Watters should have delivered Mrs Windmill's baby by caesarean section that morning, Coroner Hawkins said he instead made the "inappropriate" decision to give her a drug to speed up her labour and aim for a vaginal delivery.

In doing so, Dr Watters ignored a junior doctor's suggestion to him during a handover that morning that Mrs Windmill may need a caesarean because she had a baby that "could not be properly monitored and already showed some signs of foetal distress".

"The evidence supports the view that baby Mabel would have had a better chance of survival if she had been born earlier, but that this chance was no more than a possibility," Coroner Hawkins said.

Coroner Hawkins said while Dr Watters' attitude to the junior doctor was "problematic", and a midwife who repeatedly reported concerns to him felt he did not take her seriously, she could not say that Dr Watters' actions "were so outside of the realm of clinical judgement to have made it completely inappropriate in the circumstances".

"I find that Dr Watters was presented with a complex clinical situation which required a series of time-critical decisions. I further find that Dr Watters was genuine in his attempts to use his knowledge and extensive experience to manage Mrs Windmill's labour as best he could," she said.

Coroner Hawkins also found that while Mrs Windmill knew her weight was not ideal, the specific risks associated with having a high body mass index (BMI) were not adequately communicated to her so she could properly participate in decisions about her care.

"She was therefore not afforded an opportunity to appreciate these risks and accordingly her expectations were not sufficiently managed," Coroner Hawkins concluded.

The inquest heard that Mrs Windmill's high body mass index made it difficult for her carers to feel the position of her baby, measure the strength and duration of her contractions, and monitor the baby's heart beat with a scanner.

Coroner Hawkins said Latrobe Regional Hospital had taken the lessons learnt from the death of baby Mabel "extremely seriously" and that it was now mandatory for any woman with a BMI greater than 45 to be referred to a tertiary hospital.

She recommend that the Royal Australian and New Zealand College of Obstetricians consider more training in foetal surveillance for locum doctors who do not receive continuing professional development courses within hospitals.

Dimitra Dubrow​, a medical negligence lawyer with Maurice Blackburn who is representing the Windmill family, said they were now considering legal action against Latrobe Regional Hospital. She released a statement from the family which said they love Mabel and miss her more and more every day.

"We will always believe her death was preventable," their statement said.