It is apparent that the head of a preterm infant should not be left uncovered, however it remains unclear whether covering the head of a preterm baby with plastic wrapping is effective in preventing heat loss.

We conducted a prospective, randomised, controlled trial in very preterm infants to evaluate if a polyethylene cap prevents heat loss after delivery better than polyethylene occlusive wrapping and conventional drying. Furthermore, we assessed body temperature 1 hour after admission to Neonatal Intensive Care Unit (NICU) to evaluate whether the polyethylene cap prevents postnatal heat loss.

The primary outcome measure was axillary temperature taken on admission to the NICU (immediately after cap and wrap removal) and again 1 hour later. Axillary temperature was measured using a digital thermometer (Terumo Digital Clinical Thermometer C202, Terumo Corporation, Tokio, Japan). The occurrence of hypothermia, defined as axillary temperature less then 36.4°C, on NICU admission was also evaluated.

Secondary outcomes included mortality prior to hospital discharge, presence of major brain injury (sonographic evidence of intraventricular hemorrhage with ventricular dilatation, parenchymal hemorrhagic infarction, or periventricular leukomalacia), tracheal intubation at birth, Apgar scores, delivery to admission time, blood gas analysis and serum glucose concentration on NICU admission.

Inclusion Criteria:

• infants <29 weeks' gestation born in the study center.

Exclusion Criteria:

• congenital anomalies with open lesions (e.g. gastroschisis, meningomyelocele) and babies whose delivery was not attended by the neonatal team.