Image copyright Science Photo Library Image caption Babies with colic tend to have intense bouts of crying for several hours a day

The crying of babies with colic may be reduced if they are treated with acupuncture, according to controversial research from Sweden.

But UK experts say no conclusions can be drawn from the small study of 147 babies aged two to eight weeks.

Although colic is harmless, looking after a baby who has it can be frustrating and distressing.

NHS Choices lists a number of different ways of comforting a colicky baby. Acupuncture isn't one of them.

Colic - frequent, excessive crying in a baby who is otherwise healthy - affects up to one in five babies.

The frequent, excessive crying will normally disappear by the time the baby is six months old, but it can feel a like a very long time to get to that point.

What causes colic is unknown, but it has been suggested that indigestion, trapped wind or a gut which is sensitive to breast or formula milk could be behind it.

So what works?

There are a number of techniques that may help with colic. These include:

holding your baby during a crying episode

preventing your baby swallowing air by sitting or holding them upright during feeding

burping your baby after feeds

gently rocking your baby over your shoulder

bathing your baby in a warm bath

gently massaging your baby's tummy

The mother might also want to try avoiding drinking caffeine drinks and spicy foods if they are breastfeeding.

Some babies may also benefit from changes to their diet, such as adding drops to breast or bottle milk that aid digestion and release any bubbles of trapped air in baby's digestive system, says NHS Choices.

Of course, there might be other things causing the baby to cry, such hunger, tiredness or a dirty nappy.

Cry-sis is a support group for families with excessively crying, sleepless and demanding babies. It advises parents to make use of friends and take breaks when possible if things are tough.

"Put baby down in a safe place, walk out of the room and shut the door, take a short break. Give baby to a trusted friend or family member for a few hours if possible and use any time away from baby to look after yourself," its website says.

What about acupuncture?

In the study, published in the BMJ journal, Acupuncture in Medicine, researchers from Lund University separated the babies with colic into three groups - two of the groups received two different types of minimal acupuncture, while the remaining group received no acupuncture.

One needle was inserted to a depth of 3mm for a few seconds in the first group and up to five needles were inserted for up to 30 seconds for the second group.

Image copyright Science Photo Library Image caption Acupuncture is often used to treat joint pain in adults and recommended as a treatment for migraines

This happened twice a week for two weeks and the parents of all the babies were asked to keep a detailed diary of how often and how long their child cried during this time.

The time the babies spent crying excessively reduced in all three groups, the researchers found, but the groups given acupuncture appeared to reduce their crying at a slightly faster rate.

Dr Kajsa Landgren, study author from the faculty of medicine at the university said that the babies did not cry at all during more than half of the treatments and only cried for more than one minute during 31 out of 380 sessions.

She said parents with babies who cry for more than three hours a day on three or more days of the week should try removing cow's milk from their feeds before looking at other options, such as acupuncture, if the crying continues.

But Prof Edzard Ernst, emeritus professor of complementary medicine at the University of Exeter, said any conclusions about the therapeutic effects of acupuncture could not be drawn from the study.

"We know that colicky babies respond even to minimal attention, and this trial confirms that a little additional TLC will generate an effect.

"The observed outcome is therefore not necessarily related to acupuncture."

Dr Mike Cummings, medical director of the British Medical Acupuncture Society, said he was not aware of young babies being treated for colic in the UK using acupuncture.

Specialists in paediatric acupuncture do treat children, however.

Although the study findings were not statistically significant, Dr Cummings said "there might be an effect which could be worth investigating further".

NICE (the National Institute for Health and Care Excellence) only recommends considering acupuncture as a treatment option for:

chronic tension-type headaches

migraines

Acupuncture is also often used to treat other conditions, including: