An astonishing 75% of human brain growth (more than any other mammal) occurs post-natally. As a consequence of its immaturity the human infant is forced to rely on external regulation and support, especially in the first year of life (see Galef, 1981; Rosenbloom and Schwartz 1984; and McKenna, 1986 for further discussions). The extent to which, on a minute-to-minute basis, the infant's most fundamental physiology such as heart rate, body temperature, breathing, EEG patterns, can, and likely are, influenced by the caregiver may be the most difficult and challenging concept for sleep and SIDS researchers to accept. Yet, the human infant is the least neurologically mature mammal at birth. It experiences the longest delays in both social and biological maturation (Lancaster and Lancaster 1982)--a fact not likely to be appreciated without a comparative analysis of mammalian evolution and development, and known physiological effects of short-term separation from a caregiver, as briefly described below.
Stone age babies in a space age world gae babies
Stone Age Babies In A Space Age World ? The Biology of Western Infant Sleep and Breast Feeding in the Context of SIDS Prevention James J. McKenna Ph.D. Edmund P. Joyce CSC Chair in Anthropology Director, Mother-Baby Behavioral Sleep Laboratory University of Notre Dame La Leche League International
cultural influences on infant touching <ul><li>“ In the western world it is perhaps a great advantage for an infant to have a sensitive skin or diaper rash or some other dermatological disorder, for then, at least, it can be assured of receiving something resembling an adequate amount of cutaneous stimulation” (Montagu :1986:247) </li></ul>
Until recent, western historic periods, no human parents ever asked: Where will my baby sleep, how will I lay my baby down to sleep, and how will I feed my baby? most human parents still don’t!
For the human infant the three functionally inter-related (adaptive) components of normal, healthy infant sleep include: <ul><li>Sleep location </li></ul><ul><ul><li>(next to mother for social or co-sleeping behavior involving on-going sensory exchanges, monitoring and mutual regulation) </li></ul></ul><ul><li>Nighttime feeding </li></ul><ul><ul><li>exclusive breast feeding </li></ul></ul><ul><li>Sleep position </li></ul><ul><ul><li>Back (supine) </li></ul></ul>
Enter… human biology… <ul><li>The human “obstetrical dilemma”; </li></ul><ul><li>Human Fetal Head Size Exceeds Outlet Dimensions With Emergence of Bipedalism </li></ul>
Percentage of Adult Brain Size: Chimpanzee Infant Human Infant At Birth 3 months 6 9 1 year 2 4 8-9 45 50 60 65 70 75 85 100 25 35 45 50 60 70 80 95 *(100% at 14-17 years)
Hidden regulatory mechanisms.. calming a baby by “shhhhh..ing” A universal practice! <ul><li>prenatal sensory experiences--fetus hears rhythmic “ shhoosh--sha ” as blood pulses by infant’s ear every .10 of a second following maternal heart contraction.. </li></ul><ul><ul><li>“ chamosh (Urdu) “ sh uu” (Vietnamese) </li></ul></ul><ul><ul><li>ch utee (Serbian), “ soos ” Armenian </li></ul></ul><ul><ul><li>Hu sh - s ilen ce (English), “ s tille” (German), </li></ul></ul><ul><ul><li>“ hu sh ket” (Arabic),” sh eket (Hebrew) </li></ul></ul><ul><ul><li>“ Shuh-shuh ” Chinese, “too sst ” Swedish </li></ul></ul>(From H.Karp 2002)
Biology of Mother’s Milk Predicts Mothering Behavior <ul><li>Feed and Leave Species </li></ul><ul><ul><li>(Ungulates) </li></ul></ul><ul><ul><ul><li>High fat </li></ul></ul></ul><ul><ul><ul><li>High protein </li></ul></ul></ul><ul><ul><ul><li>Low carbohydrate </li></ul></ul></ul><ul><li>High calorie = long </li></ul><ul><li>feeding interval; </li></ul><ul><li>(to avoid predators nested infants do defecate or cry in mother’s absence) </li></ul><ul><li>Contact, Co-sleeping, And Carry Species </li></ul><ul><ul><li>(Primates—Humans) </li></ul></ul><ul><ul><ul><li>Low fat </li></ul></ul></ul><ul><ul><ul><li>Low protein </li></ul></ul></ul><ul><ul><ul><li>High carbohydrate </li></ul></ul></ul><ul><li>Low calorie = short feeding interval; </li></ul><ul><li>(carried infants cry in mothers absence and defecate spontaneously) </li></ul>
Consider the physical intimacy of the maternal-infant relationship … socially and medically obscured by western culture Balinese Mother and infant
http://www.bfnews.blogspot.com/ (2004) is this what we mean when we say….. “ a good taste in art” ?
Maternal behavior among primates extends throughout an extremely long infant and juvenile period, with prolonged periods of physical contact. Orang-Utan
1.Dis-articulated from mother… No touch; No smells; No sounds No movement; No body heat’ No breadth exchange
Diversity of Co-sleeping ( requires taxonomic distinctions) Co-bedding twins (within sensory range) partial, mixed bedsharing with Dad
Parent -infant co-sleeping is biologically and psychologically expectable, if not inevitable.
Evidence -Based Science: Infants sleeping alone in a room by themselves are at least twice as likely to die from SIDS than are infants sleeping in the company (same room) as a committed adult caregiver… Sources: Great Britain (Blair et al 1999), New Zealand (Mitchell and Scragg 1995), and European Collaborative Study (Carpenter et.al.in press, Lancet )
All-night sleep-wake histograms for five (A-E) cosleeping pairs. Mosko, McKenna et al (1993). Journal of Behavioral Medicine 16 (6). Mom Baby Wake Sleep Mom Mom Baby Mom Baby Mom Baby Baby Wake Sleep
<ul><li>Figure Synchronous breathing pauses of cosleeping mother-infant pairs. </li></ul><ul><li>McKenna, JJ and Mosko, S. (1990). Human Nature 1 (3). </li></ul>Baby > Mom >
is the human mother’s sleeping body an inherent lethal weapon against which she and her infant need to be protected…?
Race Matters In All Areas Of Infant Mortality <ul><li>“ Breastfed infants are 80% less likely to die before age 1 year than those who never breast fed, even controlling for low birthweight”; </li></ul><ul><ul><li>For every 100 deaths in the formula-fed group, there were 20 deaths in the breast fed group </li></ul></ul><ul><ul><li>Using breast feeding as the normative behavior (20 deaths in the first year) the formula group with 100 deaths, had five times as many deaths or a 500% increase in mortality.. </li></ul></ul><ul><ul><li>Forste et al 2001:108 291-296Pediatrics </li></ul></ul>
University of Notre Dame Mother-Baby Behavioral Sleep Laboratory (morning wake up) first time mothers, teen moms… Research funded by NICHD RO1
Mother-Baby Behavioral Sleep Laboratory University of Notre Dame
Variations of Safe/Unsafe Sleep Practices Infra-red Video Studies: Crib-Solitary and Bedsharing ( HD 39456-01 ) Examples: 1.Solitary-crib baby placed prone, face down; 2. Neck-wrap, head covering, pillow, solitary, crib baby; 3.Bottle-fed, bedsharing, between pillow, teen mom ,lack of maternal response; 4.Breast feeding mothers, high level of responsivity to infant;
Forste et al. 2001 “ Analysis of infant mortality indicated that breast feeding accounts for race difference in infant mortality in the United States at least as well as low birth weight does” Pediatrics 2001;108:291-296
Why Is Breast Feeding So Important to the Bedsharing Issue? <ul><li>Mother-infant co-sleeping with breast feeding is an integrated, inherently adaptive system, mutually reinforcing, appropriate, predictable; </li></ul><ul><li>Changes social and biological characteristics of infant and maternal sleep (connectedness-sensitivities) of co-sleeping dyad..different from bottle feeding pairs… </li></ul><ul><li>Functional landscape of bed environment i.e. “outcomes” different from non-breast feeding-bedsharing contexts… </li></ul>
“ Not Breast Feeding and the Risk of Post-neonatal Death In the United States” <ul><li>Studied 1204 infants who died between 28 days and 1 year from causes other than congenital anomaly/tumor.and (7740 children who lived at 1 year) (controls); </li></ul><ul><li>Longer breast feeding associated with lower risk: odds ratio range from: </li></ul><ul><ul><li>.59 95% CI 0.38-0.94 for injuries to 0.84% (95%CI:.67-1.05) for sudden infant death syndrome (SIDS); (Amin Chen and Walter J.Rogan) </li></ul></ul><ul><ul><li>“ Breast feeding has the potential to save or delay ~720 post=neonatal deaths in the United States each year </li></ul></ul><ul><ul><li>Pediatrics (2004) 113: E435-439…url:http://www/pediatrics.org/cgi/content/full/113/e435 </li></ul></ul>
The origin of supine infant sleep is traced to its role in facilitating nighttime breastfeeding in the context of mother-infant cosleeping breast feeding -> cosleeping -> supine position
Co-Sleeping with breast feeding promotes the safer supine infant sleep position Richard et. al 1996, Sleep
Mother and Infant Bedsharing Orientation on BN (in min) From: Richard et al., Sleep 19 (9) 1996 ( F ace E ach O ther)
Number of Maternal Arousals With Temporal Overlap *note sensitivity of routine bedsharing mother waking to infant arousal (no habituation!)
Mean Duration of Stage 3-4 Sleep: Why Important ? <ul><li>Schechtman et al. report that, at 3-4 months of age, siblings of SIDS victims display increased integrated delta amplitude, in early morning hours compared with controls; </li></ul><ul><li>Siblings of SIDS and ALTE infants: deficient arousal responses to hypoxia or hypercapnia; </li></ul><ul><li>SIDS victims: more difficulty awakening from sleep, fewer movements; </li></ul>*p<.o27)
Why Do Babies Co-sleep? because they are supposed to…!
At the population level “outcomes” are not explained by “practice” (Black Box) who? what? why? What kind of relationship is brought to bed ? How is bedsharing linked to quality of attachment, maternal mental health, motivation, knowledge of adverse risk factors? LEADS TO BENEFITS LEADS TO DEATH (Bedsharing Practices) How linked to family characteristics ?
SIDS..patho-physiology still unexplained after all these years <ul><li>most age circumscribed human syndrome; </li></ul><ul><li>victims peak between 4-12 weeks; </li></ul><ul><li>diagnosis by exclusion; </li></ul><ul><li>multiple etiologies </li></ul><ul><li>multiple environmental factors coalesce with infantile deficits to increase SIDS risk; </li></ul><ul><li>possible subtle deficits, effecting infants in different ways; </li></ul><ul><li>unhealthy infant? damage in the womb; </li></ul>
USA SIDS Rates 2002 (NCHS) .57 per 1000 live infants born Asian .1-.2 Hispanics .2-.4 Whites .3-.6 Blacks 1.2-1.6 Native Americans 2.7-6.6
Carpenter et.al…2004…Lancet breast feeding remained undistinguished in the sample, as was type of bedsharing “ ... About 16% percent of cases were attributable to bedsharing and roughly 36% to the baby sleeping in a separate room.
At long last! The Consumer Product Safety Commission is finally happy! Co-sleeping finally works!