Husbands beware – Hampstead is the second most adulterous area in London and it is married women who are seeking romance elsewhere.

Men and women here are more likely to have an illicit liaison than anywhere else in London apart from Richmond, claims research by the married dating website AshleyMadison.com.

The website’s chief executive Noel Biderman says that Hampstead couples are more likely to stray because of their wealth and high-powered jobs.

He said: “One major factor is affluence. An affair can be an expensive proposition – especially if it involves a permanent mistress.

“The more financially independent and successful a woman or man is, the more likely they are to have an affair.

“There is a generation of women in their 30s who are far less tolerant of being in an unfulfilling relationship and they are going to do something about it. Women are increasingly the ones going after the men and having affairs.”

Hampstead’s large French community added a certain “je ne sais quoi” to the area, Mr Biderman said.

“There are a lot of French shops in the area – so perhaps that is having an influence,” he said.

Some high profile affairs have been conducted amid Hampstead and Highgate’s streets.

Ruth Ellis became the last woman to be executed in Britain after shooting dead her lover David Blakely outside The Magdala pub in South Hill Park, Hampstead.

Broadcaster and Primrose Hill resident Dame Joan Bakewell famously had an affair with Highgate playwright Harold Pinter, which inspired his 1978 play Betrayal.

At the time the affair began in 1962, Mr Pinter was married to actress Vivien Merchant and Dame Joan was attached to TV producer Michael Bakewell.

Mr Biderman said that many cheating couples were caught out because of the “digital lipstick” left by today’s technology of Twitter, text messages and emails.

But the research suggests that couples are prepared to stray despite the risk.

Ben McKie, clinical director of The Grove counselling services, has worked with dozens of cheating couples.

He said: “People who are in high-flying jobs have more opportunity to strike up an affair.

“I have worked with a lot of people in the media from across north London who travel around the world with their job, meet exciting people and have affairs.

“They feel the need for validation or might be having a mid-life crisis. When you are wealthy and travelling, you are less likely to get caught.”

Researchers at AshleyMadison.com also found that the website’s Hampstead members had the most children on average.

Researchers discovered that 3.5 per cent of Hampstead residents had signed up to their website, which helps match married people looking an affair.