A female teacher has admitted having a sexual relationship with a teenage pupil, which was uncovered when they visited a sexual health clinic together.

Kelly Ann-Marie Burgess, 26, of Newport, Gwent, entered guilty pleas to four sexual offences involving the schoolboy, aged 16 and 17 at the time.

North Somerset Courthouse heard Burgess was caught when the teenager told a nurse at a sexual health clinic of his sexual relationship with "a 25-year-old teacher".

Burgess initially denied the affair and claimed she was simply "assisting" the boy by taking him to get "checked out" after sexual contact with a girl of his age.

Police investigations then recovered "explicit" text messages between the pair, which had synced from her phone to laptop before being deleted.

The blonde drama teacher then confirmed they had been in a relationship for seven months, stating she did not know it was illegal as he had reached the age of consent.

Burgess, dressed in a black dress and high heels, appeared ashen-faced as she admitted four counts of adult breach of trust - sexual activity with a boy in front of magistrates.

Prosecuting, Michael Collins said the relationship had lasted between January 1 and August 28 - when Burgess was arrested - last year.

"The defendant, at the material time, was working as the child's teacher," Mr Collins said.

"The defendant and child had attended at sexual health clinic when the child made some revelations to the practise nurse that he was or had been in a sexual relationship with a 25-year-old teacher and mentioned the defendant.

"The practise nurse explained that this caused her obvious concerns and there was a protocol which may mean she might need to make certain referrals in relation to this.

"The child left and returned with the defendant. A false name was given."

A police investigation began and Burgess, who taught at a school in north Somerset which cannot be named for legal reasons, was arrested on August 28 2013.

Officers conducted a search at her home and her mobile phone was seized. As the phone was being driven back to the police station, a text message from the boy was received.

The text read: "Got the police round. Don't text back, don't be scared. Just get the story straight for when they come for you."

Burgess initially denied the relationship in police interview and officers began examining her seized mobile phone and laptop.

"It would appear that while she deleted some information from her mobile phone, modern technology meant it was synced with her work station," Mr Collins said.

"It became apparent there was a number of explicit messages and it was quite clear what had been going on.

"She was interviewed again, she confirmed they had begun a relationship in January. She stated she wasn't aware it was anything illegal because, as far as she was concerned, he had reached the age of consent."

Mr Collins told magistrates at the court, in Weston-super-Mare, Somerset, the starting point for the charges was an 18-month prison sentence.

The charges state that the offences took place in north Somerset, while Burgess was in a "position of trust" in relation to the boy. Burgess sexually touched the teenager "not reasonably believing he was aged 18 or over".

Representing Burgess, Sue Cameron said: "We are not opposed to the matter being sent to the Crown Court for sentence. There are mitigating factors that I won't go into today."

Mrs Jane Corke, chair of the bench, adjourned the case for sentencing at Bristol Crown Court on April 7.

"Kelly Burgess, having considered and heard the facts in this case, it clearly deserves more punishment than we are able to give," she said.

"We are therefore committing you to the crown court at Bristol. Until then you are being given unconditional bail."

Speaking after the 20-minute hearing, a spokeswoman for North Somerset Council said Burgess had lost her job since her arrest.

"The school takes safeguarding issues very seriously and this was an isolated incident," the spokeswoman said.

"The individual teacher abused her position of trust. The school followed the correct procedures and has co-operated fully with the police.

"The teacher concerned is no longer employed by the school and has not worked at the school since August last year."