Factors associated with the transition to nonprone sleep positions of infants in the United States: the National Infant Sleep Position Study.
BACKGROUND
Studies have demonstrated strong associations between the prone sleep position (on the stomach) and sudden infant death syndrome (SIDS). In 1992, the American Academy of Pediatrics recommended that infants be placed to sleep laterally (on their side) or supine (on their back) to reduce SIDS risk, and in 1994, the national public education campaign "Back to Sleep" was launched.


OBJECTIVE
To determine the typical sleep position of infants younger than 8 months in the United States, the changes that occurred after these recommendations, and the factors associated with the placement of infants prone or supine.


METHODS
Annual nationally representative telephone surveys.


METHODS
The 48 contiguous states of the United States.


METHODS
Nighttime caregivers of infants born within the last 7 months between 1992 and 1996. Approximately 1000 interviews were conducted per year.


METHODS
The position the infant was usually placed in for sleep, and the position the infant was most commonly found in when checked during the night's sleep.


RESULTS
Ninety-seven percent of respondents in each wave of the survey usually placed their infant to sleep in a specific position. Infants were placed in the prone position by 70% of caregivers in 1992, prior to the campaign, but only 24% in 1996. Supine and lateral placements increased during this time period, from 13% in 1992 to 35% in 1996 and from 15% in 1992 to 39% in 1996, respectively. Significant predictors of prone placement included maternal race reported as black (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.68-3.26), mother's age 20 to 29 years (OR, 1.28; 95% CI, 1.09-1.50), region reported as the mid-Atlantic (OR, 1.41; 95% CI, 1.12-1.78) or southern states (OR, 1.47; 95% CI, 1.22-1.70), mothers with a previous child (OR, 1.68; 95% CI, 1.43-1.97), and infants younger than 8 weeks (OR, 0.63; 95% CI, 0.46-0.85). Infants aged 8 to 15 weeks were significantly more likely to be placed nonprone over time compared with the other age groups. Most of the risk factors for prone were significantly related in the opposite direction to supine placement.


CONCLUSIONS
The prevalence of infants placed in the prone sleep position declined by 66% between 1992 and 1996. Although causality cannot be proved, SIDS rates declined approximately 38% during this period. To achieve further reduction in prone sleeping, efforts to promote the supine sleep position should be aimed at groups at high risk for prone placement.
Willinger
M
M
Pregnancy and Perinatology Branch, Center for Research for Mothers and Children, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-7510, USA. mw75q@nih.gov
Hoffman
H J
HJ
Wu
K T
KT
Hou
J R
JR
Kessler
R C
RC
Ward
S L
SL
Keens
T G
TG
Corwin
M J
MJ
D017408:Guidelines as Topic; D006801:Humans; D007223:Infant; D007224:Infant Care / Q000592:standards*; D007231:Infant, Newborn; D016015:Logistic Models; D015999:Multivariate Analysis; D011159:Population Surveillance; D016684:Prone Position; D012307:Risk Factors; D012890:Sleep; D013398:Sudden Infant Death / Q000453:epidemiology / Q000517:prevention & control*; D016683:Supine Position; D014481:United States / Q000453:epidemiology