title: Timing and variability of postpartum sleep in relation to daytime performance.
abstract: Postpartum women have highly disturbed sleep, also known as sleep fragmentation. Fragmentation extends their total sleep period, also disrupting sleep timing. A stable and earlier sleep period among non-postpartum populations is related to better performance, physical health, and mental health. However, sleep timing has not been examined among postpartum women who are also vulnerable to daytime impairment. The study objective was to examine how the timing and regularity of sleep during the early postpartum period are related to daytime functioning across postpartum weeks 2-13. In this field-based study, 71 primiparous women wore an actigraph, a small wrist-worn device that monitors sleep and sleep timing, for the 12-week study period. Mothers self-administered a 5-min psychomotor vigilance test (PVT) each morning to evaluate the number of >500ms response lapses. They also completed a Morningness-Eveningness scale at the beginning of the study to identify chronotype. After controlling for maternal age, earlier sleep timing was associated with significantly fewer PVT lapses at postpartum weeks 9,12; a more stable sleep midpoint was associated with significantly fewer PVT lapses at postpartum weeks 2,5-13. Earlier sleep midpoints were related to more stable sleep midpoints at postpartum week 2 and a morning-type chronotype. An earlier sleep midpoint was also associated with a reduced slope of worsening PVT lapses across weeks. Across the first 12 postpartum weeks, women with earlier or more stable sleep periods had less daytime impairment than women with later or more variable sleep midpoints. Postpartum women with earlier sleep midpoints also showed less severe decrements in performance across time, which has been attributed to cumulative impacts of sleep disturbance. These data suggest that the sleep period, in addition to sleep duration and fragmentation, should be more closely examined, particularly among vulnerable women, as it may affect the neurobehavioral performance of new mothers.
authors.affiliation: Department of Psychology, West Virginia University, WV, USA.
authors.forename: Amanda L
authors.initials: AL
authors.lastname: McBean
authors.forename: Hawley E
authors.initials: HE
authors.lastname: Montgomery-Downs
mesh_terms: D056044:Actigraphy; D000328:Adult; D001288:Attention / Q000502:physiology*; D005260:Female; D006801:Humans; D009483:Neuropsychological Tests; D049590:Postpartum Period / Q000502:physiology / Q000523:psychology*; D011597:Psychomotor Performance / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology / Q000523:psychology*; D013997:Time Factors
keywords: Individual differences; Maternal; Postpartum; Psychomotor vigilance; Sleep midpoint; Sleep period
references.citation: Sleep Med. 2012 May;13(5):469-75
references.pmid: 22357064
references.citation: Obstet Gynecol. 1997 Sep;90(3):381-6
references.pmid: 9277648
references.citation: Chronobiol Int. 2002 Jul;19(4):695-707
references.pmid: 12182497
references.citation: Curr Biol. 2004 Dec 29;14(24):R1038-9
references.pmid: 15620633
references.citation: Psychiatry Res. 2011 Jun 30;188(1):88-95
references.pmid: 21237517
references.citation: Sleep Med Rev. 2011 Aug;15(4):259-67
references.pmid: 21237680
references.citation: Psychophysiology. 1966 Jan;2(3):263-6
references.pmid: 5903579
references.citation: BMJ. 1998 Dec 19-26;317(7174):1675-7
references.pmid: 9857121
references.citation: CMAJ. 2006 Dec 5;175(12):1560-2
references.pmid: 17146094
references.citation: J Biol Rhythms. 2003 Jun;18(3):183-94
references.pmid: 12828276
references.citation: J Psychiatr Res. 2001 May-Jun;35(3):165-72
references.pmid: 11461712
references.citation: Arch Gen Psychiatry. 2001 Jan;58(1):69-75
references.pmid: 11146760
references.citation: Chronobiol Int. 2005;22(2):267-78
references.pmid: 16021843
references.citation: Ann N Y Acad Sci. 2008;1129:305-22
references.pmid: 18591490
references.citation: Sleep. 2009 Jul;32(7):847-55
references.pmid: 19639747
references.citation: Behav Sleep Med. 2003;1(1):54-67
references.pmid: 15600137
references.citation: J Obstet Gynecol Neonatal Nurs. 2008 Nov-Dec;37(6):722-35; quiz 735-7
references.pmid: 19012723
references.citation: CNS Drugs. 2009;23 Suppl 2:15-26
references.pmid: 19708722
references.citation: Sleep. 2013 Jan 01;36(1):73-81
references.pmid: 23288973
references.citation: Dev Psychobiol. 2013 May;55(4):361-72
references.pmid: 22553114
references.citation: Hum Neurobiol. 1982;1(3):195-204
references.pmid: 7185792
references.citation: Behav Res Methods Instrum Comput. 2004 May;36(2):339-46
references.pmid: 15354700
references.citation: J Appl Physiol. 1953 Nov;6(5):269-82
references.pmid: 13108823
references.citation: AAOHN J. 2010 Jul;58(7):297-301; quiz 302
references.pmid: 20608568
references.citation: Sleep. 2011 May 01;34(5):581-91
references.pmid: 21532951
references.citation: Behav Sleep Med. 2004;2(1):41-9
references.pmid: 15600223
references.citation: Sleep. 2006 Dec;29(12):1609-15
references.pmid: 17252892
references.citation: J Biol Rhythms. 2006 Feb;21(1):68-76
references.pmid: 16461986
references.citation: J Obstet Gynecol Neonatal Nurs. 2009 Jan-Feb;38(1):60-8
references.pmid: 19208049
references.citation: Biol Psychol. 1978 Sep;7(1-2):37-53
references.pmid: 218642
references.citation: Pediatr Clin North Am. 2004 Feb;51(1):135-51
references.pmid: 15008586
references.citation: Cardiovasc J Afr. 2008 Jul-Aug;19(4):210-5
references.pmid: 18776968
references.citation: J Psychosom Res. 2002 Jul;53(1):529-37
references.pmid: 12127168
references.citation: Biol Res Nurs. 2004 Apr;5(4):311-8
references.pmid: 15068660
references.citation: Sleep Med. 2007 Sep;8(6):602-12
references.pmid: 17383934
references.citation: J Psychiatry Neurosci. 2005 Jul;30(4):247-56
references.pmid: 16049568
references.citation: Chronobiol Int. 2011 Nov;28(9):802-9
references.pmid: 22080786
references.citation: Sleep. 2007 Apr;30(4):519-29
references.pmid: 17520797
references.citation: Sleep. 2003 Feb 1;26(1):81-5
references.pmid: 12627737
references.citation: Am J Obstet Gynecol. 2010 Nov;203(5):465.e1-7
references.pmid: 20719289
references.citation: J Sleep Res. 2003 Dec;12(4):275-82
references.pmid: 14633238
references.citation: Prog Cardiovasc Nurs. 2004 Spring;19(2):56-9
references.pmid: 15133379
references.citation: Am J Mens Health. 2012 Jan;6(1):80-8
references.pmid: 21965183
references.citation: Semin Neurol. 2009 Sep;29(4):320-39
references.pmid: 19742409
references.citation: Semin Neurol. 2009 Sep;29(4):393-405
references.pmid: 19742414
references.citation: Arch Womens Ment Health. 2009 Aug;12(4):229-37
references.pmid: 19396527
references.citation: Int J Chronobiol. 1976;4(2):97-110
references.pmid: 1027738
references.citation: J Affect Disord. 1999 Jan-Mar;52(1-3):19-29
references.pmid: 10357014
references.citation: J Affect Disord. 2013 Sep 25;150(3):1103-8
references.pmid: 23706877
references.citation: Sleep. 1997 Apr;20(4):267-77
references.pmid: 9231952