Sex is a hot topic, but New Zealanders can be a bunch of prudes when it comes to discussing it.

The authors of Sexuality Down Under - lecturer in political science Pat Moloney and sociology lecturer Allison Kirkman - found there was little material relating to New Zealand.

"It's a tricky topic and some researchers avoid it out of caution. There's a lot of theoretical articles out there, but little that deals with the practical reality of what sex has meant to New Zealanders," says Moloney.

Kirkman and Moloney say sexuality is at the heart of our personal identities and frank talk about sex remains something New Zealanders find difficult to do.

"Ignorance ... and the social stigma and penalties attached to particular sexual identities contribute to the high emotional stakes evident when sexual issues come to the fore," they write.

New Zealanders have historically presented themselves as a small, progressive democracy and sometimes our legislation has been compared with "progressive" Scandinavian countries.

But it is a mixed bag.

The New Zealand teenage birth rate is the third highest in the OECD, prostitution law reform continues to be controversial and one contributor to the book says police are often unsympathetic towards rape victims.

The book is a series of essays by Kirkman, Moloney and other academic contributors on social historical perspectives of our sexuality.

Moloney and Kirkman say the contributors had to deal with sniggers and discouragement by their colleagues as the topic was not considered to be a topic worthy of serious academic discussion.

"Finding out New Zealanders' sexual attitudes in the past is a hard social history to do - there is not a lot of personal information," says Moloney.

New Zealand was considered to be puritanical until the sexual revolution of the 1960s unravelled rigid sexual stereotyping.

Few people had left diaries or letters detailing their sexual preferences.

Moloney got information from legislation, police records and media reports of the day.

In 1869 proposed legislation to clean up prostitution would have allowed authorities to subject a woman suspected of whoring to a genital examination.

If found to be infected with venereal disease, she could have been jailed. Men were not to be similarly investigated.

But even a straight-laced society had its share of rebels.

The New Zealand Truth newspaper first appeared in June 1905, campaigning for the rights of adults to indulge in pornography.

The nudist movement was active from the 1920s. And before World War II, pornographic postcards, pictures and texts were widely available throughout the country.

Risque vaudeville dancers clad in little more than lustrous powder and glycerine performed live stage shows.

Moloney says he is not seeking to rewrite the puritanical image, but New Zealanders need to broaden their views.

"Sexuality studied 50 years ago would have been exclusively associated with medicine, then 20 years ago gender studies became a whole new area of study.

"Now sexuality is part of social sciences and history - it is a legitimate area of historical and social inquiry outside of medicine.

"It's a hot topic and a new field," he says.

Kirkman says there is still reluctance to talk about women's sexuality openly.

"It's often the butt of jokes.

"A lot of the issues relating to women in the past have dealt with problems and pain - rape, abortions and incest for example - and sometimes the problems have overwhelmed the pleasure aspects.

"There's difficulty thinking about how sex enhances women's lives," she says.

Kirkman says the book is "the first academic book that attempts to map the sexual terrain of New Zealanders - what shapes the sexual identity of society today".

The authors admit they have not covered every topic. There is nothing on sexual experiences of older New Zealanders. And while one chapter discusses historical Maori sexuality and how Europeans viewed Maori men and women, it does not cover contemporary Maori sexuality.

"We know that Maori academics are working in this area - there was just no one available at the time we were putting the book together who could have contributed," says Kirkman.

The chapter on prostitution reveals some women feel damaged by their profession, while others confess to enjoying their work.

Parlour and escort workers are more likely to have a positive view, while sex workers on the streets assume all sex is damaging and are more likely to fear attacks.

Homosexuality in New Zealand has also long been a contentious subject.

The state's interaction with the gay community once comprised vice squad surveillance, raids on bars and prison terms.

Legislation to decriminalise homosexuality in 1986 provoked vigorous debate from the Christian right wing, but reforms won and now civil unions are allowed for gay couples.

One area where prejudices remain firm is that of sexual assault, writes contributor Jan Jordan, a senior lecturer in the Institute of Criminology at Victoria. Her research in recent years has focused on women's often negative experience of police reporting and investigative practices.

* Sexuality Down Under by Allison Kirkman and Pat Moloney, published by Otago University Press, $39.95.