Around 40% of women are said to experience low libido at some point

The hormone-releasing pill has so far only been given to female monkeys and shrews who displayed more mating behaviour and ate less.

The team from the Medical Research Council's Human Reproduction Unit in Edinburgh believe a human version could be available within a decade.

But a psychologist said low-libido was usually caused by relationship issues.

Up to 40% of women are thought to experience a lack of sex drive at some point in their lives.

'Rump presentation'

The Edinburgh team, led by Professor Robert Millar, have been looking at the properties Type 2 Gonadotrophin-releasing hormone.

When it was given to monkeys, they displayed mating behaviour such as tongue-flicking and eyebrow-raising to the males, while female shrews displayed their feelings via "rump presentation and tail wagging".

When couples come to me and they are not having sex, the last thing they want to do is examine their relationship

Lesley Perman-Kerr, psychologist

But the animals also ate around a third less food than they normally would.

Professor Millar hopes to achieve a similar rise in libido and fall in appetite in a pill for women.

He told the Scotland on Sunday newspaper: "This hormone is distributed in the brain in areas that we suspect affect reproductive behaviour.

"It is considered a major pharmaceutical endeavour to address the area of libido.

"So the next stage is to produce a drug that simulates the actions of this hormone.

"It is most likely that we will do it in partnership with a pharmaceutical firm. It could be available to women within the next 10 years."

He said it may also be possible to develop a pill which worked for men, but he has so far not carried out any tests on male animals.

But psychologist Lesley Perman-Kerr said relationship problems usually had a psychological, rather than a biological, basis.

"Some women have problems specific to libido.

"But often if they go off sex, it's more to do with their relationship than their level of libido.

"When couples come to me and they are not having sex, the last thing they want to do is examine their relationship.

"They want to believe that it's nothing to do with their relationship."