Overheating is a possible risk of swaddling if you don't take care and make sure baby isn't too hot.
Suffocating is a possible risk of swaddling if you don't take care and make sure cloth can't cover their face.
Inability to move is a possible risk of swaddling (especially if you swaddle an place baby on their stomach, although hopefully there's enough information out there that this doesn't happen too much - but one study seemed to find a higher risk in this situation so maybe it does!).
Being in a deeper sleep and less responsive to external cues is a possible risk of swaddling.
Swaddling occasionaly is possibly of higher risk than swaddling regularly and from birth.
In cultures where swaddling is common practice the risk of SIDS is very low - which suggests that swaddling is not a big risk factor for SIDS when done within the other standard practices of that culture.
Studies done in Western cultures have, in some instances, found a link between swaddling and an increase in SIDS cases. That doesn't make it a causative link, but there does seem to be a link. How does ignoring the research make things safer?
LadyOfTheFlowers - I'm glad swaddling worked for you and that all 4 of your children are fine. But a population of 4 is not statistically meaningful and shows nothing about the safety of swaddling.
Yes, as parents we have masses to worry about. Whatever we do, whatever choices we make - they all come with risks and benefits attached. All children are different, all families are different so there is no single right answer that works for everyone. All we can do is make the best choices for us, and try to find the risk/benefit profile that we are most comfortable with.