The effects did not seem to be related to changes in levels of the hormones responsible for sparking the menopause and its associated symptoms, the study shows.

The authors base their findings on 53 middle aged women, all of whom were classified as being postmenopausal -- they had spontaneously stopped having periods for a year. Their somatic (hot flushes) urogenital (vaginal dryness and urinary tract infection) and psychological (mood swings) symptoms were measured using a five point scale (MRS).

Twenty seven of the women received traditional Chinese acupuncture twice a week for 10 weeks, with needles left in position for 20 minutes without any manual or electrical stimulation. The rest were given sham acupuncture.

Hormone levels of estrogen, follicular stimulating hormone (FSH), and luteinising hormone (LH) were measured before the study began and after the first and last acupuncture sessions in both groups to see if these changed.

The results showed that those women given traditional acupuncture had significantly lower MRS scores for somatic and psychological, but not urogenital, symptoms at the end of the 10 weeks than their peers given the sham treatment. The symptom registering the sharpest fall in severity was that of hot flushes.

Furthermore, the effects seemed to be cumulative, with stronger results seen between the first and last sessions.

Estrogen levels also rose, while LH levels fell in the group treated with traditional Chinese acupuncture. Low levels of estrogen and high LH and FSH levels are characteristic of the menopause, as the ovaries start to fail.

But because of the differences between the groups in these various hormones to start with, there was little evidence to suggest that any hormonal fluctuations were themselves responsible for the changes in symptom severity, say the authors.

They suggest that the explanation for the reduced severity of hot flushes might be that acupuncture boosts the production of endorphins, which may stabilize the body's temperature controls.

The authors caution that their study was small and that they did not monitor how long symptom relief lasted, but they suggest that traditional Chinese acupuncture could be an alternative for those women unable or unwilling to use hormone replacement therapy to ease troublesome menopausal symptoms.