Police are going through hundreds of files on missing people and suicides to look for signs of "honour crimes".
Police are already looking for common links in 100 murders
Suicides among young Asian women are three times the UK average and police are to examine whether those who died had been intimidated by their family.
The BBC's Neil Bennett said most honour crimes involved women deemed to have dishonoured their family or community.
He said London police were now getting complaints of intimidation from four women a week - double previous numbers.
They will also look at cases of missing young women, the BBC's crime correspondent said.
A conference organised by the Crown Prosecution Service in London on Monday is to discuss honour crimes - which can also involve false imprisonment, men and women being forced into unwanted marriages or, in extreme cases, murders being committed.
Last September the Metropolitan Police announced new research into the culture surrounding honour killings.
The undertaking followed the conviction of Abdalla Yones for the murder of his 16-year-old daughter Heshu after she formed a relationship with a man of whom he disapproved.
Police are investigating more than 100 murders over the last decade in an effort to find any common links.
Now they have started looking at coroners' verdicts on suicides to see if the deaths could have been the result of intimidation from family members.
A spokeswoman for women's rights group Southall Black Sisters, Hannana Siddiqui, told BBC Radio 4's Today programme: "The prime cause [of suicide] is domestic violence and oppressive practices within the family.
"We've often raised how these issues may be driving women to suicide and we often raise this with the coroner's court."
CPS spokesman Nazir Afzal described it as a growing problem that the CPS had been "sensitive" about handling earlier.
"We have a problem with victims and witnesses coming forward and there is a reluctance on the part of victims because they obviously don't want to get their families into trouble.
"But our primary duty... is to ensure the safety of these people. Once we've done that, then we'll think about the investigation and the prosecution," he told Today.
He said there had been "grotesque" motivations for killing female family members such as the woman being raped by a stranger or the woman playing a dedication for someone over the radio.
"That amounted to a reason to kill her - as far as I am concerned there is no justification for that. Whilst I understand why it might happen, I don't accept it," Mr Afzal said.