The iconic 1970s book, The Joy of Sex, which became the bedroom (and elsewhere) bible for a generation, has been re-released in an updated version for the noughties.

The original book, featuring a bearded man and his partner demonstrating the art of love in intimate if sketchy detail, sold millions of copies after its first publication in 1972.

But the new edition has been brought fully up to date - for the first time by a female author, who, while praising the original author Dr Alex Comfort, says there was much that needed changing.

"Back in '72 they didn't know about hormones, about pheromones, they didn't know about certain body parts and their importance, which we now know," said author and relationship psychologist Susan Quilliam.

"A lot of research has been done. But also the whole attitude to sex has changed," she told AFP.

The new book is aimed at the couple, rather than just the men, and includes many new entries including advice on internet and phone sex, sex shops and intercourse during pregnancy.

Quilliam noted that some tips from the original had to be removed, because they were illegal.

"One of them was having sex on horseback, the other was having sex on a moving motorcycle, although I do include guidelines on how to have sex on a stationary motorcycle," she said.

The publishers of the new 288-page edition, Mitchell Beazley, said it would "reflect the current attitude to sex and help bring the joy back into sexual relationships."