Is it wrong to fake an orgasm?
According to one study, up to 80 per cent of women admit to 'faking it'. And it's not only the female of the species who do it.
Buzzfeed.com recently did its own study of the subject. Its researchers put together a selection of 'sound samples', some of which were real and some of which were fake, and asked people to tell the difference. And, it seems, it's not that easy to know which is which sometimes.
So if faking it is so rife, how does it affect relationships?
Dr Jennifer Berman, a sex expert in the USA, says: "There's a lot of pressure on women to be responsive, to make the man feel good.
She emphasises that while being responsive and making appreciative noises is a positive thing, it's not healthy for the relationship if you feel you have to pretend.