Acupuncture may hold the key to stop a baby from crying.

A new study published in the journal Acupuncture in Medicine says infants with colic - crying for more than three hours a day, for at least three days a week - had fewer symptoms after getting the traditional Chinese needling technique.

A randomised, controlled trial compared two styles of acupuncture with no acupuncture.

Among 426 infants whose parents sought help for colic, 147 took part in the study.

All infants received the usual care - plus four extra visits to public child health centres, twice a week for two weeks.

The infants were randomly allocated to three groups: standardised minimal acupuncture, semi-standardised individual acupuncture inspired by traditional Chinese medicine, and no acupuncture.

It was given by nurses with extensive experience of acupuncture.

It found that the effect of the two types of acupuncture was similar, and both were superior to standard care alone.

"Relative to baseline, there was a greater relative reduction in time spent crying and colicky crying by the second intervention week and follow-up period, respectively, in infants receiving either type of acupuncture", the study says.

More infants receiving acupuncture cried less than three hours a day - thereby no longer reaching the criteria for colic.

While no serious adverse events were reported in the trial.

The study concluded that acupuncture "appears to reduce crying in infants with colic safely."