And this from Medline - Toby

Newborns' sleep-wake patterns: the role of maternal,
delivery and infant
               factors.
 AUTHOR:
               Sadeh A; Dark I; Vohr BR
 AUTHOR
 AFFILIATION:
               Department of Psychology, Tel-Aviv University, Israel.
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 SOURCE:
               Early Hum Dev 1996 Feb 23;44(2):113-26
 NLM CIT. ID:
               96351176
 ABSTRACT:
               OBJECTIVE: The purpose of this study was to assess the
sleep-wake
               patterns of fullterm (> or = 37 weeks) newborns and to
evaluate the effects
               of specific factors including maternal gestational
diabetes, infant size and
               anthropometric measures, gender, gestational age and
delivery variables.
               METHODS: Two-hundred twenty newborns were studied in the
hospital
               nursery for a continuous 24-h period with miniature
activity monitors
               attached to the infants' ankles. The sample consisted of
102 infants of
               gestational diabetic mothers (IGDM) and 118 controls.
Anthropometric
               measurements were obtained and maternal and infant
characteristics were
               recorded. RESULTS: The newborns had a discernible diurnal
sleep pattern
               and slept twice as much during the nighttime as daytime
hours (P <
               0.001). Higher skinfold measurements correlated
significantly with
               increased quiet and motionless sleep (P < 0.05) for the
IGDM but not for
               controls. Sleep of infants born at later gestational ages
was characterized
               by increased percent of quiet and motionless sleep (P <
0.0001). No direct
               gender effects were identified. CONCLUSIONS: Multiple
factors were
               associated with the sleep-wake patterns of the newborns
on our study
               cohort including maternal glucose values during
pregnancy, increased
               measures of adiposity in IGDM, increased gestational age,
mode of
               delivery and delivery Sequence. Investigation of the
sleep-wake
               characteristics of neonates using activity monitors is a
noninvasive
               method for gaining new understanding of the relationships
between sleep
               wake activity patterns and infant characteristics.
 MAIN MESH
 SUBJECTS:
               Circadian Rhythm/*PHYSIOLOGY
               *Delivery
               Diabetes, Gestational/*PHYSIOPATHOLOGY
               Infant, Newborn/*PHYSIOLOGY
               Sleep/*PHYSIOLOGY
               Wakefulness/*PHYSIOLOGY
 ADDITIONAL
 MESH
 SUBJECTS:
               Adult
               Analysis of Variance
               Anthropometry
               Female