WASHINGTON, Nov. 21 (Xinhua) -- The use of acupuncture for children is common and acupuncture is generally safe for children when performed by "appropriately trained practitioners," Canadian researchers reported Monday in online journal Pediatrics.

Researchers at the University of Alberta looked at data from 37 studies of needle acupuncture, spanning 60 years, on children from birth to age 17, and assessed the association between needle acupuncture and various levels of adverse events in children. They found that of 279 adverse events identified, 253 were mild, one was moderate and 25 were serious.

Serious side effects included bleeding, infections, and heart and lung problems. One child may have contracted HIV. But the researchers said the serious side effects were related to substandard conditions from the care provider, rather than acupuncture's technique itself. They concluded that in trained hands, pediatric acupuncture is safe.

Acupuncture has been around for thousands of years, and traditional Chinese theory suggests needle placement helps balance the body's energy flow, called "qi". Acupuncture is sometimes used to treat headaches, migraines, back and joint pains, cramps, and chemotherapy-induced nausea. Estimates show 150,000 U.S. children undergo acupuncture each year.