Why SIDS Deaths Have Declined Since the 1990s

American children today are luckier than their parents' generation. Since 1990, the number of babies who have passed away unexpectedly in their sleep has fallen by more than 50 percent. The epidemic of sudden infant death syndrome, also called SIDS or cot death, reached its peak in the mid-to-late twentieth century and has been on the decline ever since. To keep these tragedies to a minimum and to protect as many new lives as possible, it's important to know why SIDS rates have declined so sharply. Several factors come into play to make SIDS rates lower than they were in decades past.

Back-Sleeping Prevents SIDS

Until the 1990s, parents and pediatricians alike fell to a very grave mistake. On the whole, most believed that babies were safest sleeping on their bellies, because many thought that SIDS was caused by babies choking on spit-up in their sleep. We now know that babies are by far safest sleeping on their backs, and SIDS rates have declined tremendously since the American Academy of Pediatrics began universally recommending back-sleeping for babies under one year of age. Depending on the study, babies are anywhere from 2 to 12 times safer from SIDS if they sleep on their backs compared to their stomachs, so, with the majority of parents now following expert advice for safe sleeping, rates of unexplained infant death have declined as expected.

Fewer Smoking Moms Means More Healthy Babies 
Smoking puts babies at an extremely high risk for dying of SIDS, whether they're exposed to mom's cigarettes during pregnancy, after birth, or both. Babies born to smokers are more likely to be underweight or premature, which are both risk factors for SIDS, and even if they are healthy and full-term, they are still at a higher risk than average. Secondhand smoke is also a known contributing factor to SIDS and increases based on the number of smokers in the house. Although it was fairly common for moms to smoke during pregnancy, and for parents to smoke indoors, during the 1960s, 1970s, and 1980s, there has been a fortunate decline in the number of babies exposed to tobacco, with only about 1 in 10 moms now smoking at some point during pregnancy). Because of that, we've seen SIDS rates fall tremendously (although that one mom in ten needs to quit so we can see even better numbers).

Babies Born to Moms Over 20 Are Healthier and Safer 
In 1990, rates of teen pregnancy peaked, with nearly two percent of girls between 15 and 19 years of age getting pregnant per year. Babies born to teen moms were more likely to have health problems, including higher rates of preterm birth and low birth weight, and they were also much more likely to pass away because of SIDS. Fortunately for both moms and babies, teen pregnancy now affects .7 percent of 15- to 19-year-old girls and women. Although babies born to teen mothers are still at risk, we have been lucky to see a drop in the number of SIDS deaths because fewer women are giving birth as teens.

There may be other factors that are influencing current rates of SIDS. Better prenatal health care, better nutrition, more well-visits to pediatricians, and the current vaccine schedule could also play a role. The important thing for both parents and doctors is to look at what we're doing right and keep doing it. Maybe one day in the not-too-distant future, SIDS will be remembered along with plague and smallpox, as a tragic and distant epidemic.