The trial of the man accused of the Claremont serial killings of three young women has been delayed by a week, a day after his shock guilty plea to raping a teenage girl and attacking a young woman in her home.

Key points: Edwards is accused of murdering Sarah Spiers, Jane Rimmer and Ciara Glennon

Edwards is accused of murdering Sarah Spiers, Jane Rimmer and Ciara Glennon He yesterday pleaded guilty to raping a 17-year-old girl in a Perth cemetery

He yesterday pleaded guilty to raping a 17-year-old girl in a Perth cemetery He also admitted attacking an 18-year-old woman in her Huntingdale home

The murder trial of Bradley Robert Edwards, 50, will now begin in the WA Supreme Court on November 25 after Justice Stephen Hall agreed to the delay for practical reasons.

It is now expected to take six months instead of nine after yesterday's guilty pleas to five of the eight charges he had been facing.

The trial will now focus exclusively on the three counts of murder.

Sarah Spiers, Ciara Glennon and Jane Rimmer were last seen alive in Claremont. ( Fairfax Media )

Edwards is accused of murdering Sarah Spiers, Jane Rimmer and Ciara Glennon in the upmarket Perth suburb of Claremont in the mid-1990s.

The bodies of Ms Rimmer and Ms Glennon were found in bushland following their disappearances, but Ms Spiers has never been found.

Prosecutor Carmel Barbagallo on Monday requested a delay to the start of the trial to allow time for new reports on fibre and DNA analysis to be finalised.

Justice Hall set a deadline of December 6 for this to happen.

He said the availability of the courtroom was another factor in his decision, as trial staff would not have had access to it until the night before the previously scheduled date of November 18.

Shock guilty plea

In a dramatic development on Tuesday, Edwards admitted to five other charges, including twice raping a 17-year-old girl he abducted from a park in Claremont at night and attacked at Karrakatta Cemetery.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 2 minutes 3 seconds 2 m 3 s Accused Claremont serial killer pleads guilty to historic attacks on women

He also pleaded guilty to subjecting an 18-year-old woman to a terrifying ordeal after breaking into her Huntingdale home at night.

In the Karrakatta case, which took place in February 1995, he abducted the teenager while she was walking home from Claremont, binding her hands and feet, stuffing fabric into her mouth and placing a hood over her head.

He then forced her into his car and drove her to the nearby cemetery where the two rapes took place.

The sexual assaults not only "caused bodily harm" but which were "likely to seriously and substantially degrade or humiliate" her, according to the charges Edwards admitted.

The Huntingdale attack happened seven years earlier, in February 1988, when he broke into the house of an 18-year-old who lived with her parents.

The teenager was sleeping at the time and woke to find Edwards in her bedroom after he had closed her parents' bedroom door and unplugged the family's phone.

He straddled the young woman as she lay on her stomach and tried to force a piece of cloth into her mouth, but she fought him off and he fled.

However, a distinctive silk kimono-style dressing gown was left behind, from which prosecutors say DNA was recovered and eventually matched to material recovered from the body of Ciara Glennon and from the cemetery rape victim.

A silk kimono was dropped at the scene of the Huntingdale attack. ( Supplied )

Previous attack on hospital worker

It was not until 20 years after Ms Spiers went missing that Edwards was arrested at his Kewdale home in December 2016 in connection with the murders.

He has always maintained his plea of not guilty.

The vicious attacks on the two teenagers are not Edwards's only crimes.

He has a previous conviction for attacking a woman in 1990 at Hollywood Hospital in the leafy western suburb of Shenton Park, where he was working as a Telstra technician.

The social worker was attacked from behind as she sat in an office chair, with Edwards trying to stuff a piece of cloth into her mouth.

However, she kicked him and managed to break free.

Cable ties were later found in his pocket.

Edwards was convicted of common assault and sentenced to two years' probation.