Sleeping Positions:
Sleeping Positions:
Prone position: Placing an infant on stomach to sleep.
Supine position: Placing an infant on back to sleep.
Incidences of sudden and unexplained deaths of an apparently healthy infant have occurred since the earliest of times. It wasnit until 1969 that it was given the name Sudden Infant Death Syndrome and formally recognized as a disease (Bergman & Choate, 1975). The newly revised definition of SIDS is as follows:
The sudden death of an infant younger than one year that remains unexplained after a thorough case investigation, including performance of an autopsy, examination of the death scene, and review of the clinical history (Dwyer, Ponsonby, Blizzard, Newman, & Cochrane, 1995; Gilbert-Barness & Barness, 1996; Kinney, Filiano, Sleeper, Mandell Valdes-Dapena, & White, 1995; Klonoff-Cohen, Edelstein, Lefkowitz, Sriniwasan, Kaegi, Chang, & Wiley, 1995; "Sudden infant death syndrome," 1996; Willinger, 1995).
The cause of SIDS is unknown (Bergman & Choate, 1975; Gilbert-Barness & Barness, 1996). The requirements for examining the death scene and reviewing the history allowed for greater precision in diagnosing SIDS, however the diagnosis is still one of exclusion. It is based on the absence of more specific findings obtained from a routine autopsy (Gilbert-Barness & Barness, 1996). SIDS is the leading cause of postneonatal (ages 14 to 364 days) infant mortality in the United States (Willinger, 1995). The diagnosis accounts for approximately one-third of all such deaths ("Sudden infant Death Syndrome," 1996). Almost all instances of sudden and unexpected deaths of an infant continue to be diagnosed as SIDS (Gilbert-Barness & Barness, 1996). Each year 5,000 to 6,000 infants die with that diagnosis (Andolsek, 1997; Willinger, 1995), thats one out of every 1,000 babies born (Gilbert-Barness & Barness, 1996). Most infants who die of SIDS are between one and six months old. Eighty-five percent of those victims die between the ages of two and four months, and 95% are younger than six months (Gilbert-Barness & Barness, 1996; Klonoff-Cohen & Edelstein, 1995). SIDS is so rare outside this age range that the diagnosis should be made cautiously and only when all other possible causes such as metabolic diseases are ruled out (Bergman & Choate, 1975; Gilbert-Barness & Barness, 1996). SIDS may also be confused with Shaken Baby Syndrome, which can sometimes be hard to diagnose. Hemorrhage of the retina or optic nerve is usually present in these cases, however vigorous attempts to resuscitate an infant can also be excluded in cases of accidental or deliberate poisoning determined by toxicological tests (Gilbert-Barness & Barness, 1996). This research has found that exposure to cocaine through passive inhalation, ingestion, or in breast milk is possibly lethal and could result in an unexpected and sudden death of an infant. They also suggest that coroners and medical examiners may have trouble differentiating infant deaths due to SIDS as opposed to those that may be a result od child abuse. The difficulty lies in that an autopsy cannot distinguish between SIDS and suffocation with a soft object, such as a pillow or the cupped hand of an adult. Suspicions of a deliberate suffocation should be raised if there are previous episodes of apnea in the presence of the same person, the infant is older than six months, and if there are previous unexpected or unexplained deaths of one or more infants in the care of the same person. Gilbert-Barness and Barness find that suffocation may also occur eventually in cases of Munchausen by proxy. Unfortunately the association of Munchausen with SIDS, near-miss SIDS, and Apparent Life-Threatening Episodes appears to be on the rise. In the end a diagnosis of SIDS or abuse is determined by the circumstances of death and the medical history of the family, including whether or not there are earlier deaths of the same sort among siblings (Gilbert-Barness & Barness, 1996).
There are many aspects to consider when determining risk factors for SIDS. SIDS appears to have seasonal variations, with fewer incidences occurring in summer months ("The Sudden Infant Death Syndrome," 1977). This could also reflect the increase in risks due to room temperature and heating or infections for infants who may sleep in the prone position (Golding, Limerick, & Macfarlane, 1985; Willinger, 1995). Children who are born to mothers under the age of 20 are twice as likely to die suddenly and unexpectedly than children who are born to mothers over age 25 ( Golding et al., 1985). Golding et al. (1985) also found a correlational risk to SIDS in birth order. They find that the younger the mother the higher the risk of SIDS for each additional birth. However, regardless of the age of the mother, the more children she has the higher the risk of SIDS. Virtually all studies have shown a higher mortality rate for males, suggesting perhaps that certain factors may exist that predispose them to SIDS (Klonoff-Cohen & Edelstein, 1995; "The Sudden Infant Death Syndrome," 1977). In the period from 1983-1989 male infants were 45% more likely to die from SIDS than females. In 1990-1994 they were 50% more likely to die ("Decline in SIDS rates," 1997). There is also an increased risk among low birth weight babies ("Sudden infant death syndrome," 1996; "The Sudden Infant Death Syndrome," 1977). According to The Sudden Infant Death Syndrome (1977) the risk of SIDS declines as birth weight increases. This study also finds that SIDS is not a genetic disease, which implies that a predisposition to SIDS is more closely related to extrauterine environmental factors than with post conceptional age.
The difference in risks between the various races appears to be one of socio-economic or environmental circumstances (Golding et al., 1985; "The Sudden Infant Death Syndrome," 1977). For example, incidences of SIDS tend to be higher among minority groups such as American Indians, African Americans, and Mexican Americans--not due to any racial characteristics, but because more of these families tend to live in less fortunate circumstances (Bergman & Choate, 1975). Despite its greater attack among the less privileged, SIDS does not discriminate between class or social position ("The Sudden Infant Death Syndrome," 1977).
In biblical times SIDS was attributed to "overlaying." During this time it was quite common to place babies in the same bed as parents, siblings, or a nurse to sleep (Bergman & Choate, 1975; Gilbert-Barness & Barness, 1996). It was assumed that infants suffocated when rolled upon by an adult while sleeping. While this may have happened in some cases, often when alcohol was implicated, it is still not known how co-sleeping increases the risk of SIDS (Mitchell, 1996). One possibility includes hypoxia due to the rebreathing of either their own or their parents expired air (Gilbert-Barness & Barness, 1996; Mitchell, 1996). According to Mitchell (1996) co-sleeping is often associated with breastfeeding, partly because one encourages the other. He also concludes that while there are numerous reasons to encourage breastfeeding, the protective effect of doing so is modest against SIDS. Mitchell suggests that infants should not bedshare at all, especially those infants whose mothers smoke.
Babies born to mothers who smoked during pregnancy had a risk 4.09 times higher than those whose mothers did not smoke (Gilbert-Barness & Barness, 1996). The risk became even higher when both parents smoked (Klonoff-Cohen et al., 1995). Klonoff-Cohen et al. (1995) found that mothers who smoked during conception or throughout their pregnancies and were exposed to passive smoke by the father during their pregnancy indirectly exposed the fetus to tobacco smoke, thereby increasing the risk of SIDS. They also found that passive exposure to tobacco smoke after birth provided a dose-response trend--the greater the amount of cigarettes the infant was exposed to after birth from all adults, the higher the risk of SIDS. When adults smoked in the same room as the infant the risk was even greater. This effect of exposure to passive smoke was independent of parental age, education level, maternal smoking, maternal drug use, prenatal care, sleep position, and birthweight. According to Walling (1996) postpartum exposure to tobacco smoke can triple the risk of SIDS. If parents didn't smoke during pregnancy and after birth this cause of death could be reduced by two-thirds.
In 1972 a paper was published that argued that SIDS was caused by sleep apnea and that it ran in families (Begley, 1997; Pinholster, 1995). According to Begley (1997) the paper was based on Molly and Noah Hoyt, the last two of five Hoyt children who supposedly died of SIDS due to sleep apnea. The paper became an instant classic and spawned a multi-million dollar apnea-monitor industry. Apnea is a cessation in breathing that may be as short as 15 seconds ( "Infantile Apnea," 1986). It was thought that the prone position interfered in some way with an infants effort to arouse or autoresucitate once this cessation of breathing occurs (Gilbert-Barness & Barness, 1996). In 1995, when Waneta Hoyt was convicted on five counts of murder including Molly and Noah's, the medical community began to question why they bought the whole apnea idea "hook, line and sinker" (Begley, 1997). The paper was so powerful that in many cases it kept medical examiners and pediatricians from considering homicide when an apparently healthy baby died for no reason, it also allowed for no suspicion to be raised when more than one child in a family died of SIDS. When Waneta Hoyt was convicted, the possibility of SIDS being preventable with the use of an apnea monitor also became questionable (Begley, 1997). Evidence shows that with the introduction of home monitoring, the annual rate of SIDS did not perceivably decline ("Infantile Apnea," 1986). In 1985 the American Academyof Pediatrics concluded that apnea monitors should be prescribed only in cases where an infant has had an apparent life-threatening episode (Gilbert-Barness & Barness, 1996).
In 1994 SIDS declined from the second to the third leading cause of infant death, behind low birth weight and congenital anomalies, for the first time since 1980 (Gilbert-Barness & Barness, 1996). The American Academy of Pediatrics Task Force on Infant Positioning and SIDS in May of 1992 concluded that there was significant evidence to implicate the prone sleeping position as a risk factor for SIDS and began recommending that healthy and full-term infants be placed in the supine sleep position (Gilbert-Barness & Barness, 1996). This was the largest individual contribution to the decline in SIDS and accounted for 70% of that decline (Dwyer et al., 1995). During the period of 1983-1994 the diagnosis of SIDS was given to 61,882 infants. From 1983-1990 SIDS rates declined an average of 1.6% per year, whereas during 1990-1994 the rate decreased an average of 5.6% per year ("Decline in SIDS rates," 1997). This decrease is due in part to the recommendation to avoid prone sleeping and may reflect changes in the prevalence of known risk factors and changes in the diagnosis of SIDS ("Decline in SIDS rates," 1997; "Sudden infant death syndrome," 1996). The recommendation from the AAP was soon followed in June 1994 with the national public education "Back to Sleep" campaign (Klonoff-Cohen et al., 1995). This decision was based on epidemiological evidence from overseas where a 50% or more decrease in SIDS was observed by reducing the use of the prone position.
Many parents were initially concerned that aspiration would occur if an infant were to spit up while sleeping in the supine position. This fear appears to be unwarranted and is actually less common in infants who do sleep on their backs (Gilbert-Barness & Barness, 1996). The danger of the prone position may also be compounded by excess clothing and bedding. It is possible for loose bedding to hollow out a pocket and force infants to rebreathe their own expired air which is high in carbon dioxide. An infant who cannot lift his head out of the pocket may suffocate (Gilbert-Barness & Barness, 1996; Mitchell, 1996). In 1994 the Consumer Product Safety Commission (CPSC) found that fluffy and loose bedding could trap toxic amounts of carbon dioxide ( Sandrick, 1997). That following year in 1995 the CPSC announced the results of their two year investigation of the relationship between SIDS and soft bedding. The study showed that as many as 30% of the 5,000 to 6,000 deaths diagnosed as SIDS each year are probably cases of suffocation brought about when an infant rebreaths their own expired air while sleeping face down on soft bedding. (Gilbert-Barness & Barness, 1996).
