New mother Gia Lam and infant Serena Lee died in southwest Sydney hospitals in 2019 and 2021 respectively.
Both their deaths were preventable had the medical teams used all diagnostic tools and followed correct procedures, the findings from a joint inquest said.
Ms Lam died from sepsis as a result of an untreated urinary tract infection contracted after she gave birth to her son in January 2019.
She did not have access to a Vietnamese translator when visited by a nurse during a home visit, preventing her from accurately describing her level of pain, Deputy State Coroner Rebecca Hosking found.
Once admitted to hospital, her nurse failed to identify the telltale signs of developing sepsis including an offensive smell that failed to disappear even after a shower, Ms Hosking said.
The coroner found her nurse, who had been a midwife for 12 years, failed to record any observation of Ms Lam while under her care at Liverpool Hospital.
"The standard of care provided by (the nurse) fell well short of the standard expected of an experienced registered midwife," Ms Hosking said.
An investigation into the nurse's care leading up to the preventable death of Ms Lam was recommended to the national oversight body by the coroner.
In the other strand of the inquest, baby Serena Lee was found to have been improperly discharged from hospital before her death one day after being born in 2021.
Serena's doctor at Campbelltown Hospital, who was inexperienced in pediatrics, failed to recognise the newborn was showing signs of high blood sugar when he discharged her.
She later died of obstructive sleep apnoea.
Ms Hosking was particularly scathing of the doctor, describing him as a poor witness.
"He was defensive, evasive at points, and demonstrated limited insight into the nature and seriousness of his errors," she said.
The coroner found he only reluctantly accepted ultimate responsibility for determining Serena's suitability for discharge after initially saying it was a collaborative decision.
His care of Serena was recommended for investigation by the state medical council.
The South Western Sydney Local Health District was instructed to ensure procedures for linguistically diverse patients are being followed.
They were also told to consider amending the information provided to midwives about the threshold for infant blood glucose that requires further investigation.
The health district was contacted for comment on Wednesday evening but did not provide a statement before publication.
23°C