Breastfeeding is associated with increased Non REM S3-sleep in non-depressive mothers three months post partum

Objectives: During postpartum period, mothers often experience poor sleep and fatigue. However, the impact of breastfeeding on maternal sleep has not been indisputably elucidated, although some evidence suggests that breastfeeding might promote nocturnal sleep. The aim of this study was to investigate subjective and objective sleep of breastfeeding mothers, as compared to formula feeding mothers. Methods: A total of 59 non-depressive mothers at three months after delivery (mean age: 32.8 ± 4.3 years; primipara: 51.7%) took part in the study. Of those, 44 were breastfeeding, and 15 were formula feeding. The objective sleep measure was obtained using a sleep EEG; subjective sleep quality was assessed with the Insomnia Severity Index (ISI). Results: Sleep-EEGs of breastfeeding women did not differ from controls in total sleep time, waketime after sleep onset or number of awakenings. Breastfeeding was associated with increased NREM-S3-sleep, decreased REM-sleep and reduced sleep efficiency. Subjective sleep quality did not statistically differ between both groups. Conclusion: Our results suggest that in non-depressive mothers breastfeeding affects maternal sleep structure featuring more NREM-S3-sleep and decreased REM- sleep. Given that subjective sleep did not differ, it is conceivable that these changes may be of minimal clinical relevance.

This study was supported by Gottfried und Julia Bangerter-Rhyner-Stiftung, Bern, Switzerland