SIDS – What Is It and How to Prevent
Sudden Infant Death Syndrome (SIDS) is a parent’s worst nightmare: the unexpected loss of a seemingly healthy baby, most often during sleep. While it’s rare, its impact is profound. Understanding what SIDS is, why it happens, how common it is, which babies are most at risk, and the steps parents can take to reduce that risk empowers families to make safer, more informed choices.
Key Takeaways
SIDS is the sudden, unexplained death of an infant under one year, typically during sleep.
Most SIDS deaths happen between 2–4 months, with more than 90% occurring before six months.
Parents can reduce risk through safe sleep habits like back–only sleep, room sharing (not bed sharing), and avoiding overly soft bedding.
SIDS – What Is It?
SIDS stands for Sudden Infant Death Syndrome—a diagnosis given when an infant younger than one year dies unexpectedly during sleep, and no other cause can be found even after an autopsy and investigation. Often referred to as “crib death,” SIDS remains unexplained, despite apparently healthy infants and thorough investigation.
Who Is At Risk for SIDS?
Virtually any baby under one year can experience SIDS, but certain groups are more at risk:
Typically infants between 2–4 months old, with 95% of cases before six months
Male infants are about 60% more likely than female infants to be affected
Preterm babies, those with low birth weight, and those with inadequate prenatal care are more vulnerable
Parental smoking during pregnancy or exposure to secondhand smoke increases risk
Unsafe sleep environments—soft bedding, prone sleep, bed sharing—also heighten danger
What Causes SIDS?
The exact cause of SIDS remains unknown. Research supports a multi-factor “triple risk” model:
A vulnerable infant (due to genetic, brain, or developmental factors)
A critical stage in brain development (especially 2–4 months)
An external stressor (like prone sleeping or smoke exposure)
Theories also point to problems in brain areas regulating breathing/arousal and low enzyme levels affecting breathing response. In the U.S., SIDS remains the leading cause of death for infants aged 1–12 months—around 1,500 deaths in 2022.
How Is SIDS Diagnosed?
SIDS is considered a diagnosis of exclusion, meaning it’s only determined after all other possible causes of death have been ruled out. This process typically involves a full autopsy, a detailed review of the infant’s medical and family history, and a thorough investigation of the death scene. If no other medical explanation—such as infection, trauma, or congenital disorder—is found, and the circumstances fit the profile, the death may be classified as SIDS. This careful and comprehensive process is essential not only for accuracy but also to provide families with as much clarity as possible during an incredibly difficult time.
How to Prevent SIDS
Creating a safe sleep environment is key. The American Academy of Pediatrics (AAP) recommends a series of protective steps:
Prenatal Care
Early and consistent healthcare during pregnancy—avoiding smoking, alcohol, and substance use—can lessen your baby’s vulnerability.
Sleeping on Back
Firmly placing your baby on their back for every nap and bedtime greatly reduces SIDS risk. This was the cornerstone of the ‘Safe to Sleep’ campaign, which cut SIDS rates by over 50%.
Tummy Time
While only safe when supervised and awake, tummy time strengthens neck muscles and aids developmental milestones—two protective factors against SIDS.
Proper Bedding
Use a firm mattress with a well-fitted sheet. Avoid pillows, blankets, crib bumpers, plush toys, or sleep positioners—all of which pose suffocation risks.
Stay in the Same Room
Room-sharing without bed-sharing lowers SIDS risk by around 50%. Keep the crib or bassinet in the parents’ room if possible.
Avoid Bed Sharing
Sharing a bed may increase risk, particularly if adults smoke, drink alcohol or use medications. The AAP advises separately tucked beds until at least one year.
Pediatric Healthcare
Stay current with well-child checkups and immunizations. Vaccinated infants have a notably lower SIDS risk.
Breastfeeding
Exclusive breastfeeding for six months cuts SIDS risk by about 50%. Breast milk boosts immunity and promotes lighter sleep patterns, enhancing arousal responses.
Pacifiers
Using a pacifier at nap & bedtime can help, even if it falls out mid-sleep. Pacifiers don’t interfere with breastfeeding beyond the first month.
Additional Safe Sleep Practices
Dress your baby appropriately to avoid overheating
Avoid smoking and ensure smoke-free surroundings
Skip devices without evidence—like “intelligent” monitors or sleep positioners
Ensure immunizations are up to date
Bottom Line
Understanding what is SIDS and embracing how to prevent SIDS through safe sleep choices, prenatal care, and pediatric support can significantly reduce risk. At Birthly, our childbirth education classes cover safe sleep environments, breastfeeding support, and prenatal strategies to guard against SIDS and help parents feel confident. Joining a class means being equipped—not just informed—about infant safety.
SIDS FAQ
Are there support groups for families that have experienced SIDS?
Yes. Many hospitals and non-profits—including local bereavement groups and national organizations—offer emotional support and counseling for families impacted by SIDS.
What are the warning signs of SIDS?
Sadly, there are no visible warning signs. SIDS is sudden and unexplained, underscoring the critical role of prevention rather than detection.
What age is SIDS no longer a risk?
While risk drops significantly after six months and especially after eight months, safe sleep practices should continue until your baby turns one.
How prevalent is SIDS?
In 2022, approximately 1,500 U.S. infants died from SIDS—part of roughly 3,700 total sleep-related infant deaths.