Women past the menopause who snore could have the problem relieved by doses of a sex hormone to help them breathe.

It is estimated that 15% of women suffer partial obstruction of their ariways during sleep, and the problem often emerges later in life.

While this can be a severe annoyance to their sleeping partner, it also causes oxygen in the blood to drop below normal levels.

They can find themselves suffering from intense fatigue if their sleep is affected this way over a long period.

Scientists have suspected for a while that the menopause, at which point the ovaries stop producing the hormone progesterone, may be significant.

Hormone supply

However, a team from Turku in Finland decided to test the theory that giving a synthetic version of the hormone could improve the situation.

From a group of 71 women over 50 years old, 10 were found who suffered partial airway obstruction while sleeping.

They were given doses of synthetic progesterone, then monitored again a few weeks later to see if they had improved.

Lung ventilation - the ability of the patient to fill up and empty the lungs - improved substantially with the treatment.

Waste removal

A key sign of success was that the quantity of carbon dioxide - the "waste gas" of breathing - fell by almost 15%.

Although this is not as marked an effect as using a "continuous positive airway pressure" mask - which pushes air under slightly increased pressure into the lungs - this was still considered significant by the researchers.

Dr Tarja Saaresranta said that while it was premature to recommend the treatment wholesale, there was certainly evidence that a short course of treatment might help women with such night-time breathing problems.

Even a couple of weeks after the treatment had been given, there was still evidence that it was having an effect, according to the researchers.

Their work was published in the European Respiratory Journal.