Autonomic Nervous System Changes in Term Infants during Early Skin-to-skin Contact (SSC) : Examination of SSC Effectiveness and the Influence of Meconium-stained Amniotic Fluid

[Aim] : To determine the effects of early skin-to-skin contact (SSC) and the influence of meconium-stained amniotic fluid (MSAF) on infants who satisfied the SSC indications by examining the changes in autonomic nervous system and physiological indices in term infants born with normal vaginal delivery. [Methods] : Our study population included cases that satisfied indications for implementing SSC. Study A included 12 infants who underwent SSC (SSC group) and 10 who did not (non-SCC group), and Study B included 9 infants with MSAF (SSC with MSAF group) and 12 without it (SSC with clear AF group). We measured heart rate variability (HRV), heart rate (HR), oxygen saturation (SpO2), state of sleep-wakefulness (measured continuously for 2h after birth), respiratory rate (RR), and body temperature (measured every 15 min). [Results] : In Study A, irrespective of the presence/absence of SSC, sympathetic nervous system (SNS) activities accelerated at 1h after birth, but after 2h, the SNS activity was suppressed in the SSC group. During SSC, SpO2 progressed within the normal range of >95%, and the infants were significantly more often in a state of sleep. In Study B, there was no difference in HRV, HR, RR, temperature, SpO2, and state of sleep according to the presence/absence of MSAF. [Conclusions] : SSC is effective in inducing a state of rest because it induces a state of sleep and suppresses SNS hyperactivity at 2h after birth. When SSC indications are satisfied, we demonstrated, for the first time, that MSAF has no adverse effect on infants.