After asking 5,000 adults, cynical researchers have claimed that the romantic schedule means men can catch up with their football highlights on Match Of The Day at 10.30pm.
The second most popular time for sex is 9pm on Friday, followed by 9.30am on Sunday, reports The Daily Express.
"It certainly seems that sex has become a matter of convenience for many people.
"When couples get past the honeymoon stage in their relationship they seem to settle down a bit, and sex isn't as important any more."
The survey shows a quarter of couples go longer than two months between romps.