Objective

This study investigated the relationship of daytime maternal napping, exercise, caffeine, and alcohol intake to objective and subjective sleep indices.

Participants

Sixty healthy, nondepressed, first-time mothers between 3 and 6 months postpartum.

Methods

Seven consecutive days of online behavior diaries, sleep diaries, and wrist actigraphy, collecting Total Sleep Time (TST), Sleep Onset Latency (SOL), and Wake After Sleep Onset (WASO).

Results

After controlling for infant age, employment status, infant feeding method, and infant sleeping location, mixed linear models showed that longer average exercise durations were associated with longer average TST, and longer average nap durations were associated with longer average WASO durations. Significant within-person differences in TST and SOL were also observed, such that, on days when participants exercised and napped longer than average, their respective TST and SOL durations that night were longer.

Conclusion

Shorter nap durations and longer exercise durations were associated with longer TST, shorter SOL, and reduced WASO. Even small changes in daily exercise and napping behaviors could lead to reliable improvements in postpartum maternal sleep.

Sleep and social relationships are two key determinants of psychosocial health that undergo considerable change across the transition to motherhood. The current study investigated the bidirectional relationship between daytime Positive and Negative Social Interactions (PSIs & NSIs) and nighttime sleep quality on maternal mood across 1 week in the 3-6 month postpartum period. Sixty healthy, non-depressed first-time mothers completed 7-consecutive days of daily social interaction and sleep diaries. Results indicated that higher than average sleep quality buffered the effect of higher than average NSIs on maternal mood (i.e., buffered mood reactivity) and appeared to promote mood recovery following a particularly "bad day" (i.e., higher than average NSIs). In addition, although PSIs were more common than NSIs overall, the most frequent and positively rated PSIs were with baby as were the most frequent and negatively rated NSIs. To our knowledge, our results are the first to characterize the impact of PSIs on postpartum maternal mood, assess maternal-infant social interactions in daily diary study of postpartum social relationships, and demonstrate the role that maternal sleep quality plays in social discord-related mood reactivity and mood recovery processes in the 3-6 month postpartum period.