How can putting my newborn to sleep on his back be safe if he happens to spit up?

My 3-week-old baby often falls asleep on my stomach while I'm trying to burp him. At the hospital, the doctor told me to place him on his back or side when I put him down. I've read plenty of information about Sudden Infant Death Syndrome (SIDS) and understand the risk of placing him on his stomach to sleep. How can placing him on his back be safe if he happens to be sick? Isn't there a possibility of him choking on it?

Your son is not at risk from SIDS when he is lying on your body, so don't worry about turning him when you are holding him. That's because if he were to experience some difficulty breathing, you would notice immediately. (SIDS - unexplained sudden death while an infant sleeps - occurs in one to two of every 1,000 births.) If your son sicks up frequently, you may want to place him propped on his side straight after he eats, for 30 minutes or so. If he has serious vomiting problems, discuss this with his GP. Some infants need to be on their stomachs after feeding for a variety of medical situations, but that's a call your doctor should make on an individual basis. It may also be reassuring to know that babies have a great ability to keep their airways clear of the usual small amounts of sick, so the usual directive is that babies be placed on their backs to sleep. This has already lowered the incidence of SIDS in Britain. It looks like we are on the right track with this change of policy.