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Updated: Apr 16, 2026

Multi-Modal Home Sleep Monitoring in Older Adults
Published on: January 26, 2019
Objective sleep of older primiparous Japanese women during the first 4 months postpartum: an actigraphic study
Hiroko Iwata1, Emi Mori, Miyako Tsuchiya
1Graduate School of Nursing, Chiba University, Chiba, Japan.
This longitudinal study was designed to examine objective sleep parameters of older primiparous Japanese women during the first 4 months postpartum using actigraphy. The participants were 18 older primiparae (Mean (SD) = 37.06 (2.62) years, range 35-44 years) who gave birth to healthy neonates at one of three urban Japanese hospitals. Objective sleep quality was measured using actigraphy for 48 h at 1, 2 and 4 months postpartum. The Friedman test was used to test for differences in sleep parameters across time. Sleep duration (SMIN) increased significantly from 2 months (Mean (M) = 301.94 min) to 4 months (M = 372.78 min). Sleep efficiency (SE) increased significantly from 1 month (73.52%) to 2 (86.66%) and 4 months (89.05%). Waking after sleep onset (WASO) decreased significantly from 1 month (M = 114.64 min) to 2 (M = 40.18 min) and 4 months (M = 38.36 min) and long waking episodes (LWEP) significantly decreased from 1 month (4.67) to 2 (2.69) and 4 months (3.12). Persistent postpartum sleep problems can be a sign of postpartum depression as well as health problems among infants.
This longitudinal study was designed to examine objective sleep parameters of older primiparous Japanese women during the first 4 months postpartum using actigraphy. The participants were 18 older primiparae (Mean (SD) = 37.06 (2.62) years, range 35-44 years) who gave birth to healthy neonates at one of three urban Japanese hospitals. Objective sleep quality was measured using actigraphy for 48 h at 1, 2 and 4 months postpartum. The Friedman test was used to test for differences in sleep parameters across time. Sleep duration (SMIN) increased significantly from 2 months (Mean (M) = 301.94 min) to 4 months (M = 372.78 min). Sleep efficiency (SE) increased significantly from 1 month (73.52%) to 2 (86.66%) and 4 months (89.05%). Waking after sleep onset (WASO) decreased significantly from 1 month (M = 114.64 min) to 2 (M = 40.18 min) and 4 months (M = 38.36 min) and long waking episodes (LWEP) significantly decreased from 1 month (4.67) to 2 (2.69) and 4 months (3.12). Persistent postpartum sleep problems can be a sign of postpartum depression as well as health problems among infants.
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