According to the National Institute of Health, these conditions may cause SIDS:
Abnormalities of a neural network in the brain stem that controls breathing and heart rate. If an infant is not breathing enough oxygen, their brain triggers more breathing and/or heartbeats to compensate, but only if their controls work.
Studies have shown an association between specific defective genes and mild respiratory infections in infants who have died of SIDS. Many SIDS infants have an activated immune system, which may indicate they’re vulnerable to simple infections.
Maintaining optimum air flow for breathing is the main issue for babies with the above conditions. Doing so includes preventing 1) airway obstruction from a bad sleeping position, and 2) re-breathing exhaled air collected in soft material in his bed.
When sleeping on their back, a baby’s air passages are wide open and breathing isn’t restricted in any way. Their face is away from the mattress and soft materials like bedding that collect exhaled air. When an infant who is used to sleeping on their back is placed on their stomach or side, they’re at a higher risk of SIDS—so be consistent. It’s OK when your baby learns to roll over on his own, but swaddled babies who roll over are at an even higher risk of SIDS, so it’s time to stop swaddling as soon as he starts trying.
New cribs, bassinets, and other baby beds are required to have firm mattresses that don’t collect much exhaled air. If you’re considering a used baby bed, make sure the mattress is firm and cover it with a tightly fitted sheet that won’t come loose. Couches and soft mattresses are unstable and can result in a baby turning over, too.
In addition to parents rolling over onto their babies, the risks of bed-sharing include the exhaled breath problem presented by pillows and bedding and other issues reflected in this long list of precautions suggested by a proponent of bed-sharing. If you choose to co-sleep with your baby in the bed, be very careful. The highest risk comes when either parent is under the influence of drugs or alcohol while sleeping.
If they end up next to your baby’s face, they capture exhaled air. This includes your baby rolling over and putting his face into them or grabbing and pulling them onto his face.
A scientist at Kaiser thought that good room air flow could help when exhaled air is trapped by bedding, or the baby’s breath flow is so weak that his breath collects around his face. He conducted a study that found sleeping in a room with an open window reduced SIDS by 36%, and a fan on in the room reduced it by 72%. A small fan would also produce soothing white noise.
Additional risk factors for SIDS include:
A hot baby is more likely to sleep deeply and be difficult to arouse, and excessive clothing or blankets and a higher room temperature place a baby at a higher risk for SIDS. Be careful to not overdress your baby and keep the thermostat at a comfortable temperature for you (babies don’t need to be kept any warmer than an adult). Also, swaddling can overheat your baby when he’s in a warm room. In general, if you notice sweating, damp hair, flushed cheeks, or rapid breathing, remove blanket/clothes to cool him down. Overheating may increase the risk of SIDS for a baby who has a cold or infection, so don’t increase the room temperature when he’s sick.
Babies of mothers who smoke during pregnancy are three times more likely to die of SIDS. Secondhand smoke (like from Dad) in the house doubles a baby's risk of SIDS. Scientists found changes occurred in babies’ nervous systems in areas key to arousal and breathing functions. They suspect nicotine negatively affects development of these functions and raises the risk of SIDS.
Studies indicate that for infants who received any amount of breastmilk, the risk of SIDS was 60% lower. For those breastfed at 2 months of age and older, the risk was 62% lower, and for those infants who exclusively breastfed, the risk was 73% lower. Breastfeeding reduces infections and infectious diseases tied to an increased vulnerability to SIDS.
Pacifier use at naptime and bedtime decreased the risk of SIDS from 50% to 90%. Studies also show an increased risk when a baby generally used a pacifier, but not the last time they slept, so be consistent. Recent studies and reviews found pacifier use does not negatively affect breastfeeding duration or exclusivity, so you can start as soon as you think your baby might benefit. Here’s excellent information on pacifier use from the American Academy of Pediatrics.
Have Your Baby Sleep in Your Room for One Year
In 2016, the AAP recommended babies sleep in their parent’s room for a minimum of six months and, ideally, one year. We checked out the evidence in their full report, including four sources they listed and found a very credible alternate perspective. Aaron Carroll, MD is a Professor of Pediatrics and Vice Chair for Health Policy and Outcomes Research at Indiana University. In his New York Times article, this research expert described his experience as a new parent and then reviewed the AAP’s evidence on their recommendation.
He pointed out their four studies were based on data 15 to 25 years old, before major reductions in SIDS occurred and from European countries with different sleep patterns. They were “case-control” studies, among the weaker research designs in human research, that can only indicate an association, not the cause.
He also pointed out that the AAP also did not take into account the costs in terms of lack of sleep to parents: Dr. Fern R. Hauck, a member of the AAP task force that prepared the new policy, said it hadn’t given great thought to parents’ sleep before issuing the recommendation. “Parents will probably need to get used to it,” she said.
Dr. Carroll said that while “we want to do all we can to prevent SIDS, we should do so in ways that are likely to work— and unlikely to cause harm. This recommendation leaves them with the sense that they’re supposed to watch over their babies at every sleeping, as well as waking, moment. With the demands of modern-day child-rearing, parents feel enough guilt already.”
The reason the AAP SIDS committee recommended that your baby sleep in your room for a year, much longer than when SIDS is a significant risk, is the expansion of their scope to non-SIDS injury deaths of infants. There are about 1,250 per year and most are caused by suffocation; check out our Safety section to learn how to prevent them.