Background Hypothermia is defined as core body temperature being below 36.5°C. This study aimed to identify the prevalence, associated factors and outcomes of hypothermia among neonates admitted to the premature baby unit (PBU) of a secondary care hospital in Nawalapitiya, Sri Lanka. Methods In a cross–sectional analytical study, medical records of neonates admitted to the PBU were selected retrospectively from March 2022 using consecutive sampling. The recorded axillary temperature on admission, socio-demographic and clinical data were extracted. Following bivariate analysis, multivariable logistic regression was performed. Results Among 407 neonates, the median admission age was 1 day. The majority were males (52.6%), were term (59%) and had a normal birth weight (52.5%). The prevalence of hypothermia was 38.6% (95% confidence interval (CI):33.9–43.4). Maternal factors like teenage pregnancy, multiple pregnancy, hypertension during pregnancy, premature rupture of membranes and lower-segment caesarean sections; neonatal factors like age on admission being less than 24 hours, prematurity, corrected gestational age on admission being less than 37 weeks, low birth weight, weight on admission being less than 2.5 kg and having been resuscitated at birth had statistically significant associations with hypothermia on the bivariate analysis. Hypothermia showed no significant association with the month of admission. Following multivariable analysis, age on admission being less than 24 hours (adjusted odds ratio (aOR):3.3, 95% CI:1.9–5.8), teenage pregnancy (aOR:8.2, 95% CI:1.8–37.2), multiple pregnancy (aOR:2.8, 95% CI:1.1–7.1) and hypertension in pregnancy (aOR:2.3, 95% CI:1.2–4.7) remained statistically significant. Neonates with hypothermia had 5.2 times (95% CI:1.8–14.6) odds of mortality and 4.9 times (95% CI:2.8–8.5) odds of receiving ventilatory support compared to normothermic neonates. Hypothermia also showed statistically significant associations with infant respiratory distress syndrome, metabolic acidosis and neonatal jaundice. Conclusions Nearly two out of five neonates admitted to the PBU were hypothermic. There were significant maternal and neonatal associations to be addressed. Hypothermia on admission may indicate serious neonatal morbidity and mortality. Keywords Newborn, temperature, morbidity, mortality, South Asia

The authors have declared no competing interest.

This study did not receive any funding.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee/IRB of National hospital Kandy, Sri Lanka gave ethical approval for this work. (ERC No: NHK/ERC/19/2022)

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