A role for sleep disorders in pregnancy complications: challenges and opportunities

See related article, page 52Sleep and sleeplike states have been identified in all mammalian species, other vertebrates such as birds,1Zepelin H. Rechtschaffen A. Mammalian sleep, longevity, and energy metabolism.Brain Behav Evol. 1974; 10: 425-470Crossref PubMed Scopus (209) Google Scholar, 2Campbell S.S. Tobler I. Animal sleep: a review of sleep duration across phylogeny.Neurosci Biobehav Rev. 1984; 8: 269-300Crossref PubMed Scopus (520) Google Scholar, 3Rechtschaffen A. Current perspectives on the function of sleep.Perspect Biol Med. 1998; 41: 359-390Crossref PubMed Scopus (233) Google Scholar, 4McNamara P. Barton R.A. Nunn C.L. Evolution of sleep. Cambridge University Press, New York, NY2009Google Scholar and invertebrates (eg, fruit fly or Drosophila melanogaster).5Shaw P.J. Cirelli C. Greenspan R.J. Tononi G. 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Aguera-Ortiz L.F. et al.Greater risk of Alzheimer's disease in older adults with insomnia.J Am Geriatr Soc. 2011; 59: 559-562Crossref PubMed Scopus (112) Google ScholarFigure 2Pathway to clear cellular waste from the brain using the glymphatic systemReproduced with permission from American Association for the Advancement of Science, from Nedergaard.62Nedergaard M. Neuroscience: garbage truck of the brain.Science. 2013; 340: 1529-1530Crossref PubMed Scopus (354) Google ScholarShow full captionCerebrospinal fluid (CSF) passes through the para-arterial space surrounding the arteries (top part of the Figure). This space is bound by the non-luminal surface of the blood vessel and the apical processes of astrocytes. 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