As I said, it doesn't happen to everyone, it doesn't happen to most. But is does happen. Here is someone who it happened to in Cleveland: http://www.ideastream.org/news/be-well-why-do-babies-die-in-... . Note, not on drugs, not high, not drunk, doing the "right things." Had researched co-sleeping safely etc... I head her talk on the radio about it. The cause of death was determined to be her breathing on her child's face while they were both asleep. This just isn't the kind of risk I would be willing to take.
Life is never a zero-risk game, and you need to put things in perspective with numbers, not scare stories. You do this every day when you choose to hop on a bike, get in your car or on a train and go to to work.
Parenting is personal, very personal, so do what you feel is right for yourself and your child.
Yes, infant deaths are horrific, no matter the cause(s), and make for emotionally compelling reports.
Do you have numbers on infants who die while in a crib in the same room? Another room? Bedside bassinet?
My current wife, myself and my ex all had agreed that we prefer to be more responsive to our children. My wives both are light sleepers, and woke to the slightest disturbance to check, but went right off to sleep at the all clear. I also developed this sense. A cough, a wheeze, and somehow my brain triggered me to pay attention, but not routine noises.
I never fall out of bed, never have, and neither do the majority of the population. NOTE: I prefer a mattress on the floor anyway, so even if I did, it is 7 inches to the ground. We are aware of our surroundings when we sleep. The babies have always slept between us.
Of course there are exceptions: Drugs, alcohol, people with sleep disorders like 'night terrors', hybermobile sleepers, PTSD-affected people and so on. Again, reason and education.
I will look into the 'breathing onto the face of the baby' bit, since being a technical diver, CPROX-certified and aware of related things, I would think you would have to have your exhaling nose or mouth right up against your baby rather than at breast height where they normally sleep. Ambient air usually is around 21% O2. It would take a high concentration of CO2 to displace the ambient air and to develop right at the nose or mouth, and babies tend to breath twice as fast as parents, so it doesn't seem to add up. I'd like to find numbers on that one.
Again, in the US I kept an old drafty house with lots of air exchange by default, not the typical modern American construction which tends to seal and caulk everything and keep closed doors. This keeps harmful off-gassing products trapped in your breathing space. I also didn't use much energy, since I prefer it a bit chilly vs. toasty, so the drafts and fresh air were welcomed.
It's the reason Radon remediation saw people adding active ducts to remove it from basements and such. Too tightly sealed, no air circulation. Radon is naturally occurring, and it is only when you trap the radon progeny that attach to surfaces or dust that it becomes a respiratory/radiation health concern.
For the past year, I have been living in a house in East Java, where I can see daylight through the roof tiles, and the room is very airy due to the night breeze. We sleep on a mattress on a floor, and the rice fields and trees are all around us with a volcano 13 miles due SSW (Now, that could be a risk!).
[UPDATE] Here's an interesting take from a pediatrician for 35 years, who co-slept with all 8 of his children, and wrote 2 books on the subject regarding Sids[1].
Obesity is also a barrier to co-sleeping, and usually carries other issues like sleep apnea. The US doesn't practice co-sleeping anywhere near the numbers in Asia, and I think the obesity problem is well-known.
