The high-profile trial of American woman Lindsay Clancy has ended in a mistrial after a jury failed to reach a unanimous verdict following six days of deliberations.

Clancy is accused of killing her three children before attempting to take her own life. Her defence team argued she was suffering from postpartum psychosis at the time of the alleged crimes.

WATCH ABOVE: US criminal defence lawyer Sky Lazaro said court had no choice but to order a mistrial

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After seven weeks in court, eleven jurors were firmly convinced of reasonable doubt and favoured a not guilty verdict, but one holdout juror remained unconvinced despite being sent back for further deliberations multiple times.

Criminal defence lawyer Skye Lazaro explained the court had “no other option” but to declare a mistrial when the jury remained deadlocked.

“This has been a fascinating case to watch,” Lazaro said on Weekend Sunrise on Saturday.

“The defence they raised about post-partum depression, her mental health status and the failure there.”

US judge declares mistrial in Lindsay Clancy cases Credit: NBC/AP

She explained Clancy’s defence team did everything to pause a possible retrial, however their efforts were denied by the judge.

“The defence has done everything in this case. They did a last-ditch effort, appealed to the higher supreme judicial court there, which is their court of appeals, asking for an inquiry into this juror and a stay until that can happen. That was denied after a short oral argument,” Lazaro said.

The case has now been set for a status hearing in about a month, where prosecutors will need to decide whether to retry the case or extend a plea offer.

Because the trial ended in a mistrial rather than an acquittal, double jeopardy does not apply.

“When the judge declares a mistrial, it’s basically as if the trial never happened. We go right back to where we were prior to day one of trial,” Lazaro explained.

Siblings Cora, five, and Dawson, three, and their baby brother were fatally strangled by their mum Lindsay Clancy. Credit: NBC

The case has sparked widespread debate about how postpartum mental health is handled in the US healthcare system.

“This case really has highlighted that it was the pinnacle of the defence in this case. It really gathered a lot of support for this defence,” Lazaro said.

“My hope is, and I think a lot of people watching this, is that the outcome of this is that this gets taken more seriously. So we don’t end up in murder trials.”