A HEAVILY-PREGNANT mother knocked a woman out and broke her nose when she headbutted her at a four-year-old's birthday party, a court heard.

Mother-of-three Lisa Payton's assault left Victoria Worrall needing surgery to correct a "significant degree of disfigurement", Bradford Crown Court was told.

Judge Jonathan Rose said: "This was an appalling piece of behaviour by a young woman who has never been in trouble before, who has been a hard-working woman and who, I have no doubt, is a loving mother.

"Yet, at a children's party, children witnessed your appalling act of violence where you carried out an assault on another woman."

Payton had pleaded guilty to causing actual bodily harm at an earlier hearing.

"On this particular day you, for whatever reason, allowed your temper to rise, your anger to rise, and it is that that finally spurred you to violence and a loss of self-control that one should not expect from someone of your age and a mother of children, and one who is in the latter stages of pregnancy," the judge said.

Richard Gioserano, prosecuting, said the attack happened at a play-centre on September 14 last year where Payton was hosting a party for her son.

He said that 28-year-old Payton and Miss Worrall knew each other because their partners were related.

"Both have young children," said Mr Gioserano. "Between their children there was some trouble about a week or so before that had left bad feeling unresolved."

He added that there had been an "atmosphere" after Miss Worrall arrived at the party at Megaplay, Duncombe Road, Bradford.

Mr Gioserano said Payton gave Miss Worrall "dirty looks" before words were exchanged.

The situation escalated and Miss Payton began arguing with her own brother before throwing a jug of juice at him and hitting him with a beaker and a walking stick.

"Miss Worrall got up and went over to try and calm things down," said Mr Gioserano. "It did not work and there was another heated exchange between the complainant and the defendant.

"The defendant headbutted Miss Worrall, knocking her to the ground and knocking her momentarily unconscious."

Payton then left the party and Miss Worrall was taken to Bradford Royal Infirmary.

A victim impact statement read out in court said Miss Worrall had suffered pain, discomfort, anxiety and stress since the assault.

Nikki Peers, defending, said Payton was eight months' pregnant at the time of the attack and was suffering a complicated pregnancy.

"She was under a lot of stress at the time," said Miss Peers. "She describes feeling threatened, intimidated and bullied within that family environment, and scared and vulnerable."

Miss Peers said Payton was of previous good character, was deeply ashamed of what happened, and that the incident was an "absolute one-off".

It was also said that Payton, of Leaventhorpe Lane in Thornton, was a volunteer who cared for vulnerable people in society.

Judge Rose handed Payton a 12-month prison sentence, suspended for 18 months, and ordered her to do 180 hours of unpaid work. She must also pay a victim surcharge of £100.