Significant physiological stress and disrupted sleep patterns were recorded in 2-day-old newborns who were physically separated from their mothers but remained within close proximity in the same room, according to a study in Biological Psychiatry.

Research has shown that close contact between mothers and newborns in the first few hours of life significantly improves breastfeeding rates. Sleeping in the same bed, however, is strongly discouraged in Western countries.

Heart-rate monitors recorded the physiological responses of 16 South African newborns, 10 boys and six girls, during one hour of skin-on-skin contact with their mothers and one hour facing her from a bassinet. Mothers were 17 to 40 years of age and had no post-natal complications.

Compared with close maternal contact, separation triggered a nearly three-fold increase in autonomic nervous system activity, including heart-rate and respiration changes, and an 86 percent decrease in quiet or non-rapid eye movement sleep, the study found.

A drop in body temperature could explain the sleep changes but infants aren't well evolved to cope with maternal separation, researchers said. Disrupting important early maternal-neonatal interactions may affect later development, they said.

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