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Altered sleep state patterns have been associated with various clinical entities in the perinatal period, such as infants of diabetic mothers, infants of addicted mothers and premature infants with an abnormal neonatal course. The objective of this study was to provide normative laboratory sleep state values during the first six months of life. Twelve-hour polygraphic measures were obtained in 10 full term infants during the first week of life and at 1, 2, 3, 4 and 6 months of age. Each minute of the recording was coded as Awake (AW), Active Sleep (AS) or REM, Quiet Sleep (QS) and Indeterminate (IN). A computer program calculated sleep variables. The entire study was replicated in another group (N=10). Results were assessed with an analysis of variance. The total percent of time spent in AS decreased with age. This was due to the decrease in the number of AS episodes. Both the duration of AS episodes and intervals between them remained the same. The percent of time in QS increased with age. This was due only to an increase in the duration of QS episodes. The average percent of time spent in AW and IN remained the same. The mean number of awakenings (16) at one and two months was twice as high than at four and six months. Although variability among infants was high, the age effects described were robust. Only relatively large departures from normative values are indicative of abnormal developmental patterns.

Infants with unexplained apneic episodes (Near-Miss for Sudden Infant Death Syndrome (SIDS)), are presumably at increased risk of subsequently dying of SIDS. It has been proposed that these infants exhibit prolonged sleep apnea which contributes to the mechanism leading to death. The objective of this study was to document the incidence of apnea during sleep recordings in 16 Near-Miss infants and compare the findings with those obtained from age and sex matched controls. Polygraphic records of 4 sleep and 3 cardiopulmonary variables were obtained during a 12 hour overnight recording. Successive minutes were classified as quiet sleep, active sleep, waking or indeterminate states by trained observers using standard scoring criteria. Respiratory rate and variability were calculated by computer for each minute across the night and related to sleep state. Pauses in breathing ≥3 seconds were identified in both groups. There was a tendency for Near-Miss infants to breathe faster with fewer apnea than controls, but this finding was not statistically significant. Although one half of the Near-Miss infants had recurrent prolonged apneic spells, all survived and were normal at 2 years. The proposed relationship between SIDS and apnea is not confirmed by this study.