title: Self-reported sleep in late pregnancy in relation to birth size and fetal distress: the E Moe, Māmā prospective cohort study.
abstract: OBJECTIVE
  To explore associations between features of sleep during pregnancy and adverse outcomes for the infant.
  
  
  METHODS
  E Moe, Māmā is a cohort study in Aotearoa/New Zealand that investigates self-reported sleep and maternal health in late pregnancy and the postpartum period.
  
  
  METHODS
  Women (N=633; 194 Māori) reported detailed information on their sleep duration, quality, disturbances, disorders (snoring, breathing pauses, twitching legs, restless legs) and daytime sleepiness between 35 and 37 weeks gestation.
  
  
  METHODS
  Birthweight and fetal distress during labour were extracted from medical records. Associations between each sleep variable and small or large for gestational age (SGA/LGA) using customised birthweight centile or fetal distress were estimated using multinomial/logistic regression, controlling for potential confounders. Secondary analyses considered differences in associations between Māori and non-Māori women.
  
  
  RESULTS
  There was some indication that breathing pauses (a measure of sleep apnoea) were associated with both SGA (OR 2.8, 95% CI 0.9 to 9.0, p=0.08) and LGA (OR 2.0, 95% CI 0.7 to 5.7, p=0.20), with the association for LGA being stronger when only pregnancy-onset breathing pauses were considered (OR 3.5, 95% CI 1.3 to 9.6, p=0.01). There was also some evidence that pregnancy-onset leg twitching (OR 3.3, 95% CI 1.1 to 10.0, p=0.03) and frequent sleep disturbance due to feeling too hot or too cold (OR 1.7, 95% CI 0.9 to 3.6, p=0.13) were associated with higher risk of fetal distress. Other sleep measures, including snoring, were not associated with SGA, LGA or fetal distress. Many of the associations we observed were considerably stronger in Māori compared with non-Māori women.
  
  
  CONCLUSIONS
  We did not find evidence of previously reported associations between snoring and SGA. Our findings tentatively suggest that self-reported breathing pauses and leg twitching in late pregnancy are associated with infant outcomes, and highlight ethnic inequalities.
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, UK Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Laura D
authors.initials: LD
authors.lastname: Howe
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: T Leigh
authors.initials: TL
authors.lastname: Signal
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Sarah-Jane
authors.initials: SJ
authors.lastname: Paine
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Bronwyn
authors.initials: B
authors.lastname: Sweeney
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Monique
authors.initials: M
authors.lastname: Priston
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Diane
authors.initials: D
authors.lastname: Muller
authors.affiliation: University of California, San Francisco, California, USA.
authors.forename: Kathy
authors.initials: K
authors.lastname: Lee
authors.affiliation: University of Otago, Wellington, New Zealand.
authors.forename: Mark
authors.initials: M
authors.lastname: Huthwaite
authors.affiliation: Sleep-Wake Research Centre, Massey University, Wellington, New Zealand.
authors.forename: Philippa
authors.initials: P
authors.lastname: Gander
mesh_terms: D000328:Adult; D001724:Birth Weight; D005006:Ethnicity; D005260:Female; D005316:Fetal Distress / Q000208:ethnology / Q000209:etiology*; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D011379:Prognosis; D011446:Prospective Studies; D057566:Self Report; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000150:complications* / Q000208:ethnology / Q000503:physiopathology
keywords: SLEEP MEDICINE