The "Not tonight darling, I've got a headache" syndrome is usually associated with women when they're not in the mood, but lately the excuse is increasingly being used by UK men to put off sex, according to a survey.
The new poll by independent charity the Men's Health Forum has found that 15 per cent of men aged between 18 and 59 admitted to a "lack of interest in sex".
Relationship-counselling service Relate has revealed that there's a 40 percent increase in the number of men saying they had gone off sex, compared with 10 years ago.
All the above men with low libido don't face any physical problems; it's just that they do not want to have sex.
Research has found that the growing trend of the drop in male desire is a direct result of women's changing role in society.
Men get overwhelmed with the modern woman, who is confident and comfortable with her own sexual needs and desires.
Apart from that men are bombarded with an overload of sexual images on the Internet, cable TV and in magazines, so much so, that it may be leading them to prefer the ever-ready fantasy to the reality.
Renowned Chicago-based relationships therapist Michele Weiner-Davis caused a furore in the US by claiming that at least 25 per cent of all men suffer from low desire.
It was, "America's best-kept secret," the Sun quoted her as saying.
Michael Gilbert, author of The Disposable Male, said: "Western men feel marginalised.
"In a third of American homes where both partners work, women earn more than men. This tears at the fabric of male sexuality."
And the problem is further worsened by the number of overworked men who are turning to alcohol to relax after work, and it has been revealed earlier that booze interferes with testosterone.
Phillip Hodson, a psychotherapist and author of Men: An Investigation Into The Emotional Male, said: "Sex is all about play. Libido comes out of a moment of idleness and down time. But British men work the longest hours in Europe. Sex and the clock don't go well together.
"Men drink because it's a short-cut to relaxation - but alcohol dampens the libido.