The murder of a teenage mother who was stabbed and left to die in a canal by her 17-year-old boyfriend could not have been prevented, a safeguarding children's board has said.

Laura Wilson, 17, was murdered by Ashtiaq Asghar in Rotherham, South Yorkshire, after she told his family about their relationship. Asghar was told he would serve at least 17 and a half years behind bars after he admitted murdering Miss Wilson in October 2010.

An independent report into the case of Miss Wilson, who is believed to have been known to social services since the age of 12, has now been published.

The serious case review found improvements could have been made to Miss Wilson's care but said there was no suggestion that failings by individuals or agencies led to her death, Rotherham Safeguarding Children's Board said.

The board said it had already acted on many of the recommendations made to ensure lessons were learned from Miss Wilson's murder. It said the report claimed initiatives already put in place should reduce the risk of a similar tragedy.

Alan Hazell, chair of the Rotherham Local Safeguarding Children Board, said: "This is a wide-ranging study which shows a very complex situation surrounding (Miss Wilson) and her child which made it difficult for agencies to engage with her. There is no suggestion that anyone could have saved (Miss Wilson) from what ultimately happened to her but clearly her care could have been improved.

"There were chances for those agencies to be more proactive in how they dealt with the case and all agencies involved accept that and apologise that the standards of service were not as high as they should have been.

"It is vital that agencies learn from what happened here and there is clearly a commitment in Rotherham to make that happen. As the report comments, there are already many initiatives in place to ensure that services are now improved."

Asghar had a relationship with Miss Wilson, who had a four-month-old daughter with his friend Ishaq Hussain. He killed the teenager just days after she revealed her affairs with the two men to their families.

Lord Justice Davis said he believed Asghar treated white girls as "sexual targets" and not like human beings as he sentenced him at Sheffield Crown Court in December last year. He said he thought Asghar, of Holmes Lane, Holmes, Rotherham, had treated Mr Hussain, who was cleared of murder, as a mentor.