In Sync with the Family: Children and Partners Influence the Sleep-Wake Circadian Rhythm and Social Habits of Women

Different factors have been proposed to influence morningness-eveningness, biological rhythms, and sleep-wake cycles, but few studies focused on the influence of social habits. Here, we focus on the influence of children and partners on the social habits of women at different stages of their lives and on synchronization within the family. One hundred and seventy-nine women participated in the study and were allocated into four groups: women without children, pregnant women without children, pregnant women with children, and non-pregnant mothers. Morningness was predicted by the presence of children, and earlier chronotype was predicted by the presence of children, pregnancy, and age. Average sleep duration was longest in pregnant women. The presence of children was responsible for a difference in rise times of approximately 1.5h on the weekend. Subjective sleep-onset latencies were shortest in women with children. The synchrony between partners (husband/wife) was 0.46 in women without children, 0.79 in pregnant women, 0.40 in women with children, and 0.56 between mother and child. Partners' chronotypes were highly correlated, as were those of mother and child. This study suggests children have a strong influence on their mother's lifestyle and sleep-wake rhythm, far beyond the first months of life, and that children are a more important social factor than the male partner.