During the first year postpartum, women experience suboptimal sleep duration and poor sleep quality. Most previous studies examining factors influencing sleep did not consider the dynamic nature in this period. We hypothesize that factors associated with the mother’s sleep change during this period. Methods: Women who gave birth to a singleton infant at ≥37 weeks gestation participated in the study (n=81). Participants wore an Actiwatch Spectrum Plus on their wrist at 6-8 weeks, 4 months, 6 months, and 12 months postpartum for one week to assess sleep. Covariates were assessed at each time point including sociodemographic and psychosocial variables, factors related to providing night care, physical activity (by hip-worn actigraphy), and weight retention (weight minus pre-pregnancy weight). Multiple linear regression models with night sleep duration (TSTnt) or percent sleep (Psleep, percentage of epochs scored as sleep in the night sleep interval) as the dependent variable were run for each time point. The initial model included covariates with moderate or stronger bivariate association with the dependent variable. The independent variable with the weakest correlation was subsequently eliminated, and the model was re-run until no variables can be dropped (p ≥ 0.15). Results: TSTnt was 410±62 (mean±SD), 404±54, 408±53 and 414±47 minutes at the four timepoints, respectively. Associated factors included weight retention, sleep start time, Psleep, chronotype, and whether back to work at 6-8 weeks, race and sleep start time at 4 months, race, total activity, sedentary time, and self-reported sleep quality at 6 months, and race, sleep start time, and whether providing night care at 12 months. Psleep at night was 86.6±4.8, 89.4±4.0, 89.7±4.2, and 91.1±3.7% at the four timepoints, respectively. Associated factors included TSTnt, sedentary time, household income, first time giving birth, infant wake ups at night, housing type, environmental noise, relationship status, and breastfeeding at night at 6-8 weeks, nighttime sleep, environmental noise, and breastfeeding at night at 4 months, and night sleep time, infant wakeups at night, and housing type at 6 months, and none at 12 months. Conclusions: Factors associated with TSTnt and Psleep are dynamic in the postpartum period, with different factors influencing sleep duration versus quality. Behavioral factors, such as time going to sleep and sedentary time could be intervention targets to improve postpartum women’s sleep.
Wang et al. (Tue,) studied this question.