A study of Australian sexual habits has found we are having less sex than a decade ago, but are engaging in a wider variety of activities.

The Australian Study of Health and Relationships involved about 20,000 men and women aged between 16 and 69.

According to the survey, heterosexual couples were having sex an average 1.4 times per week, compared to 1.8 times per week a decade ago.

• Stage is set for Abbott vs Putin 

Lead author Professor Juliet Richters said researchers were surprised by the declining frequency of sex, blaming technology and the increased demands of professional life.

“We think it might be the intrusion into people’s home lives of work – checking your work emails last thing before you go to bed, taking your laptop and mobile to bed, and a lot of sort of individual entertainment rather than doing things together,” she said.

“It might also be … and this is more positive … a drop in the amount of… servicing sex.

“In a lot of heterosexual relationships, even if both the man and the woman are interested in having more sex and would like to have more of it, it’s often the man who is driving the frequency.

“So then women are often kind of going, ‘Look, I’m exhausted but do it if you like’… if there’s less of that happening, that would reduce the frequency.”

Among the study’s other findings was an improvement in attitudes towards homosexuality, while Australians were found to be less tolerant of sex outside committed relationships.

“What we’ve found is that it’s been an increasing sense of openness and permissiveness around sexuality, but also at the same time an increase in desire for fidelity in relationships as they exist at the moment, so people in relationships want to stay in that relationship,” Professor Chris Rissel said.

“People are saying that they want to be faithful in the relationship, and that’s increased from last time.”