Sudden Infant Death Syndrome: Finally, We Have Some Answers

Research is shedding light on congenital causes for some “inexplicable” deaths

In my grandmothers’ days they called it “blue baby” or “cot death,” the terrible phenomenon doctors now call sudden infant death syndrome, or SIDS. It’s horrible when these babies come into the ER – found dead and blue in their cribs, the parents start CPR and call 911, hoping and praying for a miracle. It usually doesn’t happen. Instead, we finish the code and call time of death, then comfort the parents. It’s hard to explain to parents why their healthy baby suddenly died in his crib, without any apparent cause. Do these babies just die peacefully in their sleep? Or do they struggle to breathe and suffer? Could someone have prevented this? I never had answers to these questions, leaving parents to suffer in our medical ignorance.

Finally, we now have some real answers for parents about the cause of sudden infant death syndrome.  

Research published in the medical journal "Pediatrics" shows that most infants who die of SIDS had underlying brain stem abnormalities. Specifically, they had abnormalities in serotonin levels and receptors, as well as GABA receptors and 14-3-3 (a protein that regulates serotonin). So it’s not just suffocation that causes SIDS. Babies who die of SIDS often have a brainstem abnormality that prevents them from responding appropriately to a lack of oxygen. 

When you fall asleep with a blanket over your face, you wake up. But some babies have immature brain stems that can’t recognize this lack of oxygen correctly, so they don’t wake up and move.
 
We don’t know what babies have these brainstem abnormalities. There is no diagnostic test that can detect an infant at risk for SIDS. Dr. Hannah Kinney, the author of this and many other studies on SIDS, hopes to one day develop such a diagnostic test. For right now, though, SIDS can be prevented by keeping babies in safe sleep environments, putting them to sleep on their back and away from suffocation hazards. In her conclusions, Dr. Kinny emphasizes the need to continue practicing safe sleep for infants.

The "ABC’s" of SIDS help us remember how to keep our babies safe while sleeping:

Babies should sleep ALONE, on their BACK, in a CRIB.

Yet these ABC’s of safe sleep are the center of controversy, especially among breastfeeding mothers who share a bed with their baby. Bed-sharing increases the risk of infant suffocation. The vast majority of pediatricians agree that the safest place for a baby to sleep is in the same room as their mother but not in the same bed.
 
Dr. Sears, Dr. McKenna, and Dr. Burke are three pediatricians well known for supporting bed sharing, against research that shows cosleeping increases risk of SIDS. I applaud their efforts to improve maternal-infant bonding and breastfeeding. But I feel that the death statistics speak for themselves. In 2011, 57 Missouri infants died while sharing a bed with a parent according to the state’s Child Fatality Review program. And the risk of sudden death during sleep increases by 15 times when a parent sleeps in the same bed as an infant. It is true that substance abuse increases risk of bed-sharing death, as does sleeping with your infant on a couch. Parents should be specifically counseled about these risks. But many deaths were not associated with substance abuse or couch sleeping.

Supporters of bed sharing often tell me that humans have bed-shared with infants for most of antiquity. The difference today, however, is that modern American bedding is much softer and more prone to causing suffocation than the kind of bedding that has been used for most of antiquity. We also do not have statistics on how many infants died while bed-sharing through history.

Here are the most common questions I hear about safe sleep:

"How long should my baby sleep on his back?"
The American Academy of Pediatrics recommends that babies sleep on their backs until they are one year of age. As a mother, I know this is hard to accomplish!  Put your baby to sleep on his back from the time he is born and let him learn to be a back sleeper. Do not let him sleep on his belly even if he is on your chest. Do not let him sleep on his side.

“What if my baby spits up while he is sleeping on his back? Will he choke?”
No, neurologically healthy babies cannot choke on their own spit-up, even if they are sleeping on their backs. They may cough a bit but this is normal.

“I have a crib set with a bumper, blanket, stuffed animal and other matching pieces. Is it safe?”
No. Nothing goes in a crib except the baby and a tight fitting crib sheet. The “crib sets” marketed by many retail stores include many unsafe items. Never use a blanket in your baby’s bed except to swaddle the baby as described below. Bumpers are not recommended because many experts feel they are a suffocation hazard. Never put pillows, blankets, stuffed animals, or other objects in your baby’s bed.

“Can I swaddle my baby like they did in the nursery at the hospital?”
Yes, you may swaddle your baby tightly until he knows how to get out of his swaddling blanket, which usually occurs within the first month. “Wearable blankets” and swaddling blankets with Velcro closures are now highly recommended to keep your baby warm and safely swaddled. They can also help your baby sleep for longer periods of time at night, which means you get more sleep, too! Be careful that your baby is not too warm.  

“Can I use a sleep positioner or wedge?”
Sleep positioners and wedges are now considered suffocation hazards. Only a few years ago these were marketed as SIDS prevention devices, yet now they are known to be dangerous. If your baby spits up a lot or has been diagnosed with gastroesophageal reflux, you may consider raising the head of the crib mattress. Remember, nothing goes in the crib except the baby and a tight fitting crib sheet.

“I like to sleep with my baby, especially when she needs to feed during the night. Is this safe?”
Sleeping with your baby in the same bed puts your baby at significant risk for suffocation. It is especially dangerous to sleep with your baby on a couch, a waterbed, or a bed with a comforter. Sadly, many babies die when they get wedged between a parent and a couch cushion or get their faces buried in bedding. As a breastfeeding mother myself, I know how hard it is not to co-sleep while breastfeeding. Breastfeeding itself reduces SIDS risk and has many other benefits to mother and baby, so please don’t let a fear of suffocation discourage you from breastfeeding. Bedside bassinets and other cribs can make life easier when your baby wakes frequently in the night for feeding. Be sure that your baby’s bed is SIDS safe, though. Many beds such as “Moses baskets” and beds with soft bedding and blankets are not safe.

Personally, I recommend “co-sleepers,” three-sided cribs that abut the edge of a parent’s bed. Most co-sleepers meet safe sleeping recommendations. They are especially helpful for breastfeeding mothers. It is easy to breastfeed even every 1-2 hours as needed, then simply place her back in her “co-sleeper” crib where you know she is safe and you can sleep soundly. And your feet never have to touch the floor. Of note, the American Academy of Pediatrics feels there is insufficient research to recommend for or against “co-sleepers.” I, however, do recommend them as a sort of compromise between bed-sharing and crib sleeping. I feel co-sleepers really are the best solution to optimize breastfeeding and maternal-infant bonding while minimizing risks of suffocation/SIDS.

Additional resources regarding SIDS are available from SIDS Resources, a St. Louis-based not-for-profit network providing free bereavement services for Infant Loss and educational information relating to Sudden Infant Death Syndrome.

Kathleen M. Berchelmann, MD is an Assistant Professor of Pediatrics at Washington University School of Medicine in St. Louis, and a mother of five young children. She is a regular contributor to Aleteia, ChildrensMD, CatholicPediatrics, and CatholicMom, as well as multiple TV and radio outlets. Connect with Dr. Berchelmann at KathleenBerchelmannMD.com.