Assumption: Swaddling is good for babies.
Swaddling has been proved to comfort newborns and help their brains regulate, but there are dangers in swaddling as well. Hip dysplasia can be caused by swaddling an infant with legs straight. This article sums up the research on this problem and has pictures of the best way to swaddle a baby.
My Views: Swaddling has become more and more used in the past decade or so, as infants have been put on their backs to sleep (to avoid SIDS). Newborns startle easily and swaddling seems to help some babies feel more secure when placed on their backs. If you observe a newborn, you will see that the natural position of the hips is flexed. Swaddling with this natural position in mind can help prevent hip dysplasia (misalignment of the hip joint). As a side note, those who like to “wear” their babies should keep this positioning in mind as well. If your baby is hanging from his/her crotch, the legs are not in a natural position. A carrier that allows the baby to “sit” with hips flexed is better for the baby’s development.