Pregnant mother-of-one Kerry Horsfall, 31, (pictured) of Pontefract, West Yorkshire, had sex with the boy at her home during a 25 day affair

A pregnant care worker, 31, has been jailed for five years for having sex with a 'vulnerable' 14-year-old boy - using condoms he had been given during a school sex education class.

Mother-of-one Kerry Horsfall, of Pontefract, West Yorkshire, had sex with the boy at her home during a 25-day affair in 2013.

She was only found out after the boy's parents discovered messages between the pair and called police.

A court heard Horsfall, who is just months away from giving birth to her second child, first kissed the boy during a game of hide and seek.

During their brief affair Horsfall and the boy exchanged 1,738 Facebook and text messages.

A jury heard the care worker, who works with elderly people, told the boy she loved him and 'wanted to be with him'.

His parents contacted the police after spotting some of the messages the pair had exchanged on the boy's laptop.

The boy told police officers they used condoms which had been handed out during a sex education class at school during their sexual encounters.

During her trial at Leeds Crown Court Horsfall denied having sex with the boy, claiming he had been 'infatuated' with her.

She said the boy had set up a fake Facebook account pretending to be her and sent the messages to himself but was found guilty of three counts of sexual activity with a child.

Sentencing Horsfall, Judge Sally Cahill QC, said: 'The evidence in this case in my view was overwhelming.

'Your argument that the messages were sent by the victim from different tablets and mobile phones was complete nonsense.'

The court heard the boy still had feelings for Horsfall and was 'worried about what was going to happen to her'.

Judge Cahill said: 'He thought it was something that he enjoyed, something that he wanted.

'You were the adult in this situation, you should have kept him at arms length. But you encouraged him.

'You told him you loved him, you told him you wanted this with him.

'That is not the sort of conduct one expects from a woman of your age.'

During her trial at Leeds Crown Court (pictured) Horsfall denied having sex with the boy, claiming he had been 'infatuated' with her - but she was found guilty of three counts of sexual activity with a child

Jeremy Lindsay, mitigating, told the court she had no previous convictions and was previously of good character.

DC Elkie Gardner of the Wakefield Child Safeguarding Unit said: 'This has been a complex and long-running investigation and we welcome Horsfall's sentencing this afternoon.

'She knew her vulnerable victim was under the age of sexual consent and yet both created and encouraged the circumstances for the offending to take place.

'Despite a large volume of evidence against her, she still put her victim through the ordeal of a full trial.

'Wakefield police will not tolerate child abuse of any kind and will take positive action against perpetrators.'