What Happens to Your Baby's Cortisol When They Sleep Alone

Where your baby sleeps at night may affect how their stress system develops. Researchers in the Netherlands followed 163 mothers and babies through the first seven weeks of life, measuring cortisol responses to everyday stressors based on sleeping arrangements. Babies who slept alone showed higher cortisol reactivity to mild stressors compared to those who co-slept. I also cover the neuroscience of infant co-regulation — why babies cannot self-regulate their stress response in early infancy, and why caregiver proximity at night is a biological expectation rather than a habit to break. Study referenced: Tollenaar et al. (2012) — Psychoneuroendocrinology, Radboud University Nijmegen Subscribe for science-based parenting content: @mumscience I am not a medical professional. Always consult your GP or health visitor for guidance on your baby's sleep arrangements.