According to the results of a global survey older men are more satisfied with their sex lives than their female equivalents.
The survey found that the vast majority of people who are married or who have a partner remain sexually active throughout the second half of their lives and age had little effect on sexual well-being.
The study involved surveying 27,500 people between the ages of 40 and 80, including equal numbers of men and women across 29 countries.
The study's intention was to draw out people's personal views of the role of sex in their relationships with partners.
It included questions about how physically or emotionally satisfying their relationships were and how important sex was to them.
They were also asked about their overall happiness; physical and mental health circumstances, including sexual dysfunction; their attitudes toward sex; and their attitudes toward various social and demographic factors, including age, education, income and religious affiliation.
This is the first large-scale international study to include large numbers of respondents from diverse religious traditions, including Christian, Jewish, Muslim, Buddhist and other Asian religions, and atheists.
A particular focus was the impact of aging, health conditions and socio-cultural context on sexual well-being.
According to the international team of researchers factors such as health problems or depression had a substantial impact on a person's sex life.
The study found that people reported the greatest sexual satisfaction in four countries, led by Austria, and followed by the United States, Spain and Canada.
At the low end of satisfaction were Japan and Taiwan. Countries such as Turkey, Egypt and Algeria were in the middle.
The survey examined how they viewed their sex lives, their health, and their happiness and found that for a greater proportion of people in Europe, North America, and Australia, where men and women have equality in their relationships, sex was an enjoyable experience both physically and emotionally.
The research indicated that fewer people reported satisfying sex lives where men have a dominant status over women, such as nations in East Asia, and the Middle East, and in poorer countries, but the gender gap of 10 points remained consistent across the world.
On average men reported higher levels of satisfaction with their sex lives than women.
Lead author, Edward Laumann, the George Herbert Meade Distinguished Service Professor in Sociology at the University of Chicago, says in the survey there was a bias towards married people who were prepared to talk about their sex lives, and towards urban populations in less-developed nations.
Laumann says procreation is the rationale for sex, and pleasure is not "part of the story" in sexually conservative cultures in the Far East such as China, Indonesia, Japan, Taiwan, and Thailand.