Mothers' wakefulness at night in the post-partum period is related to their infants' circadian sleep-wake rhythm.

The relationship between a post-partum mother's wakefulness at night and her infant's circadian sleep-wake rhythm was examined. The subjects were seven primipara and their infants. Actigraphic recordings for the mothers and their infants were made over three to five continuous days during Weeks 3, 6, 9 and 12. A 24-h peak of autocorrelograms of the infants' movements appeared in two cases at Week 6, in six cases at Week 9, and in seven cases at Week 12. The mothers' night-time movements significantly decreased from Week 3 to Week 12. Mothers' wakefulness during night sleep in the post-partum period is related to their infants' obtaining circadian sleep-wake rhythm.