Educated, healthy, successful - and more than twice as likely to become a criminal.

Escalating crime and violence has been exposed as the nasty underbelly of post-feminist New Zealand, in a study that evaluated women's wellbeing over half a century.

Experts say the trends can in part be seen as the dark aftermath of women's liberation, where girls learn to become more aggressive while men are left struggling to cope with the change.

"Women can do just what men can do in any context, and this [crime] is one context," said Professor David Fergusson, a psychologist and director of the Christchurch Health and Development Study.

"Liberalising anything opens up greater opportunities, both for better and for ill," he said.

The study, "Well-being of Women in New Zealand: The changing landscape" by Associate Professor Gail Pacheco at AUT, looked at a range of post-sexual revolution data - including demographic information, education, employment, and health indicators. Crime was the only indicator that considerably worsened during the time frame.

For example, since 1980 alone, the proportion of women perpetrating crime increased by 70 per cent. Violent crimes, such as "acts intended to cause injury", showed the biggest spike, increasing by 115 per cent. For Maori and Pacific Island women, that rose to 160 per cent.

Not only were women more violent than their forebears, they were more likely to become victims, with family violence statistics ranking well above the OECD average.

New Zealand had a higher rate of "intimate partner" violence against women than countries such as Australia, Denmark and Japan, and a higher female assault death rate than Canada, Australia, the United Kingdom or Ireland.

Pacheco said the findings were "concerning" and needed further work to establish what was behind them.

She said women's mental health was also an area of concern highlighted by the study, and wondered if it was related to the crime figures.

"Modern women juggle so many things - work and family life, while still not gaining wage equality - no wonder there's increasing stress and anxiety."

Researcher Donna Swift, the author of The Girls Project that looks at teenage violence, said that anxiety began at an early age.

"A lot of girls feel a lot of expectation - what they should look like, how they should behave, who they should end up with, getting good marks," she said.

"When they get frustrated and can't cope with that, they turn aggression on themselves or to the world."

Swifts said the door to violence had been opened by a "normalising" of antisocial behaviour that society did not previously tolerate. That included girls becoming more aggressive - trying to be "one of the boys" - and modelling themselves on role models that were beautiful and tough, rather than the educated and articulate leaders teenagers used to look up to.

Subconsciously, many women viewed men as having more power so they therefore tried to be more like them, she said.

"There is still something those girls see in male culture that they want. It's a real step backward."

Fergusson, whose 35-year study of a birth cohort of 1265 children born in the Christchurch region in mid-1977 makes him an expert in correlational data, said one of the biggest drivers behind the rise in violence could be seen as the liberalisation of attitudes to drunkeness.

"There are now more drunk women on the streets and more females drinking, compared to the 1960s when women weren't even allowed in bars."

However, Fergusson said violent behaviour often came hand-in-hand with a whole range of other social issues such as limited education, lack of job opportunities, early pregnancy and childhood abuse or violence.

Pacheco's study also identified research that found survivors of abuse and poverty were more likely to go on to commit crime themselves.

But Criminologist Dr Jan Jordan, from Victoria University of Wellington, felt it was a "flawed" assumption to link increasing victimisation of women to the increasing numbers of female offenders.

"Yes some victims become offenders but most victims do not," she said.

Jordan, like most experts spoken to for this story, felt that in part, the increasing female violence figures were due to lower tolerance for bad female behaviour and were getting too much attention.

"It deflects from women as victims, which is a much wider issue," she said.

Jordan said the same complex social change that was driving violence among women was also in part behind the high rates of victimisation. Part of the problem was that although women's roles had changed in the past 50 years, many of the old gender values and stereotypes still held true in New Zealand, creating tension between the sexes, she said.

For example, while society had opened the door for women to work, they were still expected to - and do - the majority of the housework and childcare.

"That creates an incredible amount of pressure and strain on a relationship," she said.

"Add that to the insecurities of men - because women are now socialising with men, not just other women and children, not being at home and they have less time for their partners - that's a pretty explosive recipe right there."

Jordan said there was still a huge shift needed before women could be considered truly equal.