A female prison guard has herself been jailed after it emerged she planned to have a baby with her gangster inmate lover.

Alison Sharples, 46, became besotted with 31-year old Marvin Berkeley after he sent her love letters from his cell at Category B Garth jail in Leyland, Lancashire.

The pair vowed to be together after his release from prison and she got jealous whenever his 'moll' girlfriend turned up for prison visits in make-up and stilettos.

As part of their plans to have a baby, Berkeley handed her a plastic bag containing his sperm so she could artificially inseminate herself when she clocked off duty.

Alison Sharples has been jailed for having an affair with jailed gangster Marvin Berkeley (right)

But the seven week affair was exposed following a routine search of Sharples' handbag as she made away past a prison security gate for a night shift at the jail in October 2014.

A custody manager seized a purple medicine syringe with the plunger depressed and traces of semen on the inside which was matched by DNA testing to Berkeley.

A month later police searched Sharples' home and found a handwritten letter from Berkeley hidden carefully in her underwear drawer.

At Preston Crown Court, Sharples, a grandmother from Chorley who has since worked as a cleaner and as a carer, was found guilty of misconduct and was jailed for nine months.

Sharples who was working as a support officer at Garth met Marvin after he was moved to the 847 inmate jail and the affair began just weeks before he was due to be freed on parole.

Camille Morland prosecuting said: 'She engaged in an inappropriate relationship with a serving prisoner which went far beyond what was expected by way of her employment and was of a sexual nature.

'It was an intimate relationship, albeit within the practical constraints under which it existed.

'Their relationship was close, covert and sexually intimate, if not necessarily physically so. She seemed besotted by Berkeley and she had been promised by him they would be together when he was released from prison.'

The court heard Sharples would get jealous when Berkeley's girlfriend came to visit him

Sharples took a syringe of Berkeley's semen which she planned to use to inseminate herself

Miss Morland added: 'During a search a purple syringe applicator was found and inside of that was a clearish residue, a very small amount. She was asked at that point what it was - but she said it was for giving a baby Calpol.'

Sharples initially said she was unaware of the sperm but later admitted she was given the syringe by the inmate who said he wanted to have a baby with her.

She said she washed the fluid out and did not think it was appropriate to discard it in prison and put it in her bag, forgetting to discard it.

Work colleague Nicola Ball claimed she had tried to warn Sharples off Berkeley and said the officer had even told her she had taken a phone into jail for her lover.

Ball added: 'I tried to reiterate that the people they are on the inside isn't the same person they are on the outside. She said she and Marvin had been talking about the possibility of having a baby... so a syringe was used for that.'

Berkeley, from Salford, was serving a prison term for kidnap and firearms offences.

A friend who discouraged Sharples from the relationship said the syringe was for insemination

He and his twin bother Michael, were jailed in 2007 after police investigating Manchester crime gang The Fallowfield Mandem had found incriminating pictures of the pair smiling proudly with guns.

Officers discovered the photographs - taken on digital cameras and mobile phones - during raids on the homes of the gang, who hijacked cars and kidnapped motorists in Greater Manchester.

Victims would be targeted in the street and one was shot in the back with a bullet which later took surgeons six hours to remove.

Marvyn Berkeley was jailed in 2013 after a series of kidnappings in Manchester

Another terrified man was kidnapped and told he would 'chopped to pieces' unless he agreed to work for the gang.

Marvin got an indeterminate sentence for public protection, with a minimum of seven years after pleading guilty to conspiracy to kidnap, possess a firearm with intent to endanger life and conspiracy to commit robbery.

As part of the investigation into Sharples, police seized Berkeley's handwritten letter in a chest of drawers in her bedroom.

The prosecutor said: 'It had been slid in between the front of the drawer and underwear. From the position of the letter the officer was of the view it had been placed carefully in the drawer rather than being stuffed.'

Expert analysis comparing the text with Berkeley's handwriting.

It read: 'I don't trust no one in here. I can't talk to you properly on them walkways but whoever has reported you for talking to me has took the p*** and is totally out of order.

'I know it's not no other con so beware of the people you're working with. Look close to home Alison.

'You didn't even have to tell me you got reported for talking to me - that shown me more, how much of a genuine person you are, so thankz a lot for being you. I appreciate it so much. Be strong.'

The couple's relationship sprung up while Berkeley was serving time at HMP Garth

Passing sentence Judge Simon Newall told Sharples: 'You had worked in the prison service for a period of 10 years and appeared to have been a respected officer. I have seen a number of references that paint you in a good light. You are hard-working and have a family and care for the elderly.

'But you attempted to become pregnant with this man's child and there was communication between you outside the prison when he was inside the prison.

'The work in the prison service carries a high degree of public trust and responsibility and the integrity of a prison service is dependent on officers acting in a professional manner.'