title: Maternal caffeine consumption and infant nighttime waking: prospective cohort study.
abstract: OBJECTIVE
  Coffee and other caffeinated beverages are commonly consumed in pregnancy. In adults, caffeine may interfere with sleep onset and have a dose-response effect similar to those seen during insomnia. In infancy, nighttime waking is a common event. With this study, we aimed to investigate if maternal caffeine consumption during pregnancy and lactation leads to frequent nocturnal awakening among infants at 3 months of age.
  
  
  METHODS
  All children born in the city of Pelotas, Brazil, during 2004 were enrolled on a cohort study. Mothers were interviewed at delivery and after 3 months to obtain information on caffeine drinking consumption, sociodemographic, reproductive, and behavioral characteristics. Infant sleeping pattern in the previous 15 days was obtained from a subsample. Night waking was defined as an episode of infant arousal that woke the parents during nighttime. Multivariable analysis was performed by using Poisson regression.
  
  
  RESULTS
  The subsample included 885 of the 4231 infants born in 2004. All but 1 mother consumed caffeine in pregnancy. Nearly 20% were heavy consumers (≥300 mg/day) during pregnancy and 14.3% at 3 months postpartum. Prevalence of frequent nighttime awakeners (>3 episodes per night) was 13.8% (95% confidence interval: 11.5%-16.0%). The highest prevalence ratio was observed among breastfed infants from mothers consuming ≥300 mg/day during the whole pregnancy and in the postpartum period (1.65; 95% confidence interval: 0.86-3.17) but at a nonsignificant level.
  
  
  CONCLUSIONS
  Caffeine consumption during pregnancy and by nursing mothers seems not to have consequences on sleep of infants at the age of 3 months.
authors.affiliation: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.
authors.forename: Iná S
authors.initials: IS
authors.lastname: Santos
authors.forename: Alicia
authors.initials: A
authors.lastname: Matijasevich
authors.forename: Marlos R
authors.initials: MR
authors.lastname: Domingues
mesh_terms: D000328:Adult; D001143:Arousal / Q000187:drug effects; D001938:Brazil; D001942:Breast Feeding; D002110:Caffeine / Q000008:administration & dosage / Q000009:adverse effects*; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007223:Infant; D018730:Infant Behavior / Q000187:drug effects*; D007231:Infant, Newborn; D008297:Male; D015999:Multivariate Analysis; D016012:Poisson Distribution; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012959:Socioeconomic Factors; D014851:Wakefulness / Q000187:drug effects*; D055815:Young Adult
chemical_list: D002110:Caffeine