Savita Halappanavar died from an extremely rare and aggressive infection which an expert from the National Maternity Hospital had only seen five times in his 40-year career.
Three experts told the inquest that the 31-year-old dentist had died as a result of septic shock with the presence of an antibiotic-resistant Ecoli infection -- and this had caused her to suffer multi-organ failure.
The young woman had been strong and healthy prior to the aggressive infection spreading rapidly through her system.
The post-mortem found no evidence of any underlying condition that could have contributed to her death.
Dr Peter Kelehan, a former pathologist with the National Maternity Hospital in Dublin, who reviewed the post-mortem findings for the inquest, said there were "classic signs of septic abortion" present in the case.
He said such cases were extremely rare and he had only seen four or five cases in his 40-year career. In all of those cases the mothers had survived.
He added that of the 700 to 800 miscarriages he would have seen each year, it was highly unusual to come across the level of infection that was present in Savita's case. "It is exceedingly rare to find this level of inflammation," he said.
Dr Kelehan highlighted the need for swift action in cases of acute chorioamnionitis, an infection of the foetal membranes, and told the inquest that the infection grows rapidly in such cases as a result of the death of the placenta tissues during miscarriage.
According to Dr Kelehan, signs of septic abortion were evident in the placenta in Savita's case.
The expert witness agreed with Eugene Gleeson, counsel for Praveen Halappanavar, that such an infection would set alarm bells ringing when viewed under microscope, adding that it was "so important that you pick up the phone and make the call".
The former pathologist added that in his opinion the baby and placenta would have been dead before the rapid growth of this infection. "This is why it is so important to remove this tissues so quickly once the baby is dead," he said.
Earlier the inquest heard from Prof Grace Callagy, of UHG, who carried out the post-mortem on Ms Halappanavar. She recorded the cause of death as septic shock with the presence of an 'esbl' strain of Ecoli infection. A further factor in her death was the miscarriage at 17 weeks associated with the onset of acute chorioamnionitis, an inflammation of the foetal membrane.
Prof Callagy told the inquest that multiple swabs had been taken which showed the infection had been an ascending infection that most likely originated in the patient's rectum and travelled up the genital tract to her uterus. She added that there was no other focus of infection found anywhere. This view was shared by Dr Kelehan and Dr Sebastian Lucas who is considered the foremost expert in sepsis in the UK.
Prof Callagy agreed with Coroner Dr Ciaran MacLoughlin that when Ms Halappanavar's membranes ruptured the patient was vulnerable to that infection. She added that she had rarely come across such a case.
Praveen Halappanavar did not attend yesterday's hearing, with his solicitor Gerard O'Donnell saying he had found earlier evidence very distressing.
Mr O'Donnell added that Mr Halappanavar would return to the inquest today to hear the jury's verdict.