"Our study shows that most older people consider sexual activity and associated feelings to be a natural part of later life," according to lead researcher Nils Beckman of University of Gothenburg in Sweden.

For their study, the researchers surveyed over 1,500 septuagenarians who were asked about their sex lives including their sexual activity, marital satisfaction as well as sexual dysfunction over 30 years from 1971 to 2001.

They found that the number of men and women continuing to have sexual intercourses into the old age has increased in both sexes. Among married men, it rose from 52 per cent to 68 per cent and among married women from 38 to 56 per cent.

The unmarried also enjoyed more sex, rising from 34 per cent to 54 per cent among men. Unmarried women over 70 saw the biggest rise in sexual activity -- more than tenfold -- from 0.8 per cent to 12 per cent, The Independent reported.

A substantial proportion report having sex once a week or more, 31 per cent of the sexually active men and 26 per cent of the women.

However, while female sexual satisfaction has increased, satisfaction has decreased among men. Though men are performing better, thanks to anti-impotence drugs, they are enjoying themselves less, the study found.