Sudden Infant Death Syndrome: What It Is And How To Prevent It
It’s every new parent’s biggest fear: One moment, baby is sound asleep and the next, she’s not breathing. By definition, Sudden Infant Death Syndrome (SIDS) has no known cause. It’s extremely rare, but a small percentage of babies do die in their sleep within the first year of life, without warning or explanation. The best way to decrease baby’s SIDS risk is to always keep her in a safe environment, especially while sleeping. Here’s what you need to know about SIDS risk factors and how to prevent SIDS as best you can.
What Is SIDS?
SIDS is defined as the “sudden and unexpected death of a baby (under a year old) that remains unexplained after a thorough death scene investigation, autopsy and review of clinical history,” says Debra Weese-Mayer, MD, professor of pediatric autonomic medicine at Northwestern University’s Feinberg School of Medicine and chief of the Center for Autonomic Medicine in Pediatrics at the Lurie Children’s Hospital of Chicago and Stanley Manne Children’s Institute. Since it strikes when baby is sleeping, SIDS is also sometimes called “crib death”—which is something of a misnomer, since cribs don’t contribute to SIDS risk. (They’re in fact the safest place to put baby to sleep.)
SIDS is actually part of the umbrella term Sudden Unexpected Infant Death (SUID), which includes babies who die unexpectedly in the first year of life due to a number of reasons, including:
- Accidental suffocation (when baby gets tangled in soft bedding)
- Entrapment (when baby gets trapped between two objects and can’t breathe)
- Overlay (when another person rolls on top of or against baby)
- Strangulation (when baby gets something wrapped around his neck)
SUID can occur if baby is placed to sleep on his stomach, in an adult bed or on a couch, in a bed with other children or adults or in a sleep space that includes blankets, soft bedding, toys or crib bumpers, says Deborah Campbell, MD, FAAP, chief of neonatology at the Children’s Hospital at Montefiore in New York City. But while these deaths are often referred to as “sleep-related,” they’re not categorized as SIDS, Campbell says, since there’s a clear cause of death.
How common is SIDS?
SIDS is the leading cause of death among infants 1 to 12 months old, and about 1,600 babies died from SIDS in the US in 2015, according to the US Centers for Disease Control and Prevention (CDC).
But those SIDS statistics used to be much higher: In 1993, 4,700 babies died from SIDS, according to the American Academy of Pediatrics (AAP). Since then, the number of annual SIDS deaths has been on the decline thanks to an increased focus on awareness and education. The “Back to Sleep” campaign, for example, was launched by the US National Institute of Child Health and Human Development and other agencies in 1994 to promote putting babies to sleep on their backs on a firm surface and following other safe-sleep practices.
When Does SIDS Occur?
“By definition, SIDS includes infants under one year of age,” Weese-Mayer says. “But 95 percent of SIDS deaths occur by 6 months of age. The peak SIDS age range is between 2 and 4 months of age.”
Age is the primary factor in assessing SIDS risk in babies. While other considerations may come into play—like location, environment, race and ethnicity—there’s no conclusive research that defines how these other factors play into a child’s SIDS risk. It used to be believed that SIDS was more common during the colder months of the year, Campbell says, but we now know that time of year has no bearing on the likelihood of SIDS.
Causes of SIDS
What scares parents the most about SIDS is that there’s no known cause. Not surprisingly, the lack of a clear answer has sparked frequently asked questions about the potential causes of SIDS.
Many people ask, “Is SIDS genetic?” The answer is no—but fatal genetic mutations are sometimes mistaken for SIDS until they are discovered during an infant autopsy. “Some infants diagnosed as dying from SIDS have rare gene mutations that affect the function of the heart’s conduction system or change how the body’s metabolism works,” Campbell says. “These mutations can lead to a deadly heart arrhythmia or, in the case of a metabolic disorder, cause a buildup of chemicals that cause baby’s breathing and heart to fail. These babies die from a sudden unexpected death, but not from SIDS.”
Others wonder if there’s a link between SIDS and vaccines, but there’s no conclusive research that shows vaccines are…