Objective: To assess features of sleep among pregnant women.
Methods: We conducted a prospective cohort study of low-risk pregnant women in a tertiary perinatal centre (CHUS) in Eastern Townships, Quebec. Sleep was assessed during the second trimester (mean gestational age 16.1 +/- 3.0 weeks) (T2) and third trimester (mean gestational age 27.5 +/- 1.8 weeks) (T3) using a validated self-administered questionnaire, the Pittsburgh Sleep Quality Index (PSQI). Scores in this index range from 0 to 21, representing the cumulative scoring of seven sleep components. Subjects with a score > 5 were identified as "poor sleepers." Descriptive, bivariate, and regression analyses were performed.
Results: Among 260 consenting women, 192 (73.6%) had a term delivery without any adverse outcome. There were no differences in sleep parameters between pregnancies with adverse outcome and without adverse outcome. Mean overall PSQI scores showed evidence of deterioration in sleep quality from T2 (5.26 +/- 3.16) to T3 (6.73 +/- 4.02; P < 0.01). This deterioration was displayed in five of seven sleep components (P < 0.01). Scores in the "poor sleeper" range were recorded by 36% of women in T2 and 56%, of women in T3 (P < 0.01). "Poor sleep" in T2 and T3 was associated with low or high weight gain (P < 0.01), annual family income < $40,000 (P = 0.03), and single motherhood (P < 0.01). There was a trend for a seasonal influence on sleep scores (P = 0.08). The only predictor of poor sleep using multivariate analysis was single motherhood (P < 0.01).
Conclusion: Sleep is disturbed in early pregnancy and is worse in the third trimester. Interventions to improve sleep should be sought to optimize quality of life for pregnant women.