Swaddling, or the art of wrapping a baby in a blanket for warmth and security, has been used for many generations across the world, but a new study shows that swaddling a baby may increase the risk of sudden infant death syndrome or SIDS.

The study, published in the journal Pediatrics, shows that swaddled babies that are put to sleep on their sides or abdomen may increase the risk of SIDS.

Researchers analyzed the data from four studies involving 2,519 infants, of which 760 died due to SIDS. On the other hand, 323 of the infants involved in the study are swaddled, including 133 that died of SIDS.

"We only found four studies and they were quite different, and none gave a precise definition for swaddling making it difficult to pool the results. We did find, however, that the risk of SIDS when placing infants on the side or front for sleep increased when infants were swaddled," said Dr Anna Pease, from the School of Social and Community Medicine and lead author of the study, in a statement.

According to the study, swaddled babies sleeping at their back have 93 percent increase risk of SIDS compared to babies that are not swaddled. On the other hand, swaddled babies asleep in their stomachs and sides have 10 times and three times risk of having SIDS respectively.

The age of the babies also play a crucial role in the link found between swaddling and SIDS. Researchers noted that the risk of SIDS is higher for older babies, about six months old and older, due to their new found ability of rolling to their stomach while sleeping.

Researchers then advised that swaddling babies should be stopped once the baby start being able to roll over.

According to the report of Centers for Disease Control and Prevention, there are about 3,500 reported cases of SIDS each year, and 25 percent of those deaths are caused by accidental suffocation and strangulation in bed.

Swaddling has been taught in majority of hospitals. It is used to mimic the environment of the woman's womb, soothing and relaxing the babies.