Sleep Duration and Sleep Loss During Pregnancy: a Longitudinal FinnBrain Birth Cohort Study

PURPOSE:To investigate sleep duration and sleep loss during antenatal period and assess associative factors, including maternal characteristic and mood symptoms. METHODS:A cohort of 3038 women was enrolled. Self-reported sleep duration and sleep loss, the latter being calculated from preferred sleep need and actual sleep duration, were measured in early, mid- and late pregnancy, and at delivery. The associations with age, BMI, parity, education, smoking, napping, and depressive and anxiety symptoms were evaluated. RESULTS:Sleep duration was longest in early pregnancy and shortest at delivery (7.93 h-7.76 h, p < 0.001). The proportion of short sleepers (< 6 h) increased from 1.4% to 5.9% throughout the studied period (p < 0.001). Mean sleep loss remained stable in early- and mid-pregnancy, lowering in late pregnancy (p < 0.001) and increasing again until delivery (p = 0.003). The number of women with notable sleep loss (> 2 h) was similar during the first three measurement points (9.4%, 8.9% and 9.5%), but increased until delivery (14.1%, p < 0.001). Older, multiparous, and more-depressive women slept less (p < 0.001, p < 0.001, p = 0.017). Women with higher BMI were more likely to sleep < 6 h in late pregnancy (p = 0.012). Multiparous, more-depressive, and higher-BMI women reported more sleep loss (p < 0.001, p < 0.001, p = 0.049). CONCLUSION:We confirmed earlier reported decrease in sleep duration at the end of pregnancy. As a novel finding, we showed a notable increase in sleep loss during the last month of pregnancy. Various factors were associated with both short sleep and sleep loss, especially multiparity, napping and depressive symptoms.