Reference range for target oxygen saturation in late preterm neonates delivered by cesarean section following delayed...

To develop reference range for target oxygen saturation levels during the first 10 min of life in late preterm neonates born by cesarean delivery.

A prospective observational study conducted at a tertiary hospital in India between April 2022 and September 2024 included 200 late preterm neonates delivered by cesarean section following delayed cord clamping. Preductal peripheral oxygen saturation (SpO₂), heart rate, and temperature were recorded every minute at 2-10 min after birth.

The mean (SD) gestational age and birth weight were 35.6 (1.3) weeks and 2260 (496) g, respectively. The median (q1, q3) preductal SpO₂ at 2, 5, and 10 min were 77 (70, 84), 88 (82, 92) and 95 (93, 96), respectively. The median (q1, q3) time taken to reach saturations of ≥ 80%, ≥ 85% and ≥ 90% were 4 (3, 5), 5 (3, 6) and 6 (4, 7) minutes, respectively. Only 73.3% late preterm neonates reached the target SpO₂ of ≥ 80% at 5 min; 98.8% reached ≥ 85% at 10 min without any intervention.

Nearly one-fourth of healthy late preterm neonates did not reach the thresholds laid by the Neonatal Resuscitation Program (NRP) until 5 min after birth, yet nearly all achieved the ≥ 85% threshold of SpO₂ by 10 min without intervention. This suggests a slightly delayed but adequate transition, indicating routine supplemental oxygen may be unnecessary in clinically stable late preterm neonates.