A mother has been jailed for performing sex acts on a 14-year-old schoolboy after she initially spotted him playing football.

The 39-year-old woman, from Victoria, has been sentenced to two years behind bars, with a minimum of 10 months after abusing the boy who went to the same school as her daughter.

The sentencing comes after she pleaded guilty in a Victorian court to two counts of sexual penetration of a child under the age of 16.

The boy was just 14 years old when the then 36-year-old woman engaged in sex acts with him on two separate occasions at her home.

A mother has been jailed for performing sex acts on a 14-year-old schoolboy after she initially spotted him playing football (stock image)

The woman initially denied the abuse when interviewed by police in 2015 before telling them 'something that lasted five seconds can ruin my life forever', the prosecution told a plea hearing last week.

The woman told police the sex acts were consensual.

'It's not just me - he has been part of this as well,' she said in a record of the interview.

The sentencing judge on Friday described these remarks as 'wrong and misguided'.

The woman flirted with the boy, instigated the sexual contact and had asked the boy if she could touch his genitals, according to the prosecution summary.

After he was abused, the teenage boy became depressed, underperformed at school, and tried to numb his feelings with alcohol (stock image)

After he was abused, the teenage boy became depressed, underperformed at school, and tried to numb his feelings with alcohol.

His parents did not understand the changes in their son until the offending was exposed.

He was diagnosed with post-traumatic stress disorder and despite having treatment, was still struggling with what happened, his mother said in a victim impact statement.

In sentencing, the judge noted the woman had been sexually abused by her stepfather between the ages of 10 and 18.

Her stepfather was later jailed for abusing her and the woman never received treatment for the long-term stress and trauma the abuse caused.

He was diagnosed with post-traumatic stress disorder and despite having treatment, was still struggling with what happened, his mother said in a victim impact statement (stock image)

The judge described the woman's offending as 'opportunistic' rather than predatory.

'You are not a sexual predator and do not suffer from any sexual deviancy,' he said.

But she had exploited the circumstances and ignored her responsibility as an adult to protect children, he said.

Defence had earlier asked the judge not to jail the mother and instead sentence her to a community corrections order, but the judge said he could not ignore the harm caused to the victim.