Table 2 Observational studies measuring SpO₂ in the first few minutes of life in the delivery room where some infants were treated with 100% oxygen.

Study	Gestation	Type of oximeter	Sensor location	Resuscitation	n	SpO2 %			Comments
						1 min	5 min	10 min
Sendak et al26	Term and preterm	Nellcor N‐100	Postductal	No infant received oxygen	25	63*	89*	NA	Vaginal delivery
					34	27 (4)†	72*		C/S
				100% oxygen given	27	48 (5)†	69*		C/S and oxygen
House et al14	Term and preterm	Nellcor N‐100 or Ohmeda Biox 3700	Preductal	19/38 vaginal deliveries and 53/62 C/S received 100% oxygen	100	58 (22)‡	82 (14)‡	89 (6)‡
				No infant received oxygen	28	78 (9)‡	84 (14)‡	90 (5)‡	C/S and vaginal deliveries
Deckardt et al19	>37 weeks	Nellcor N‐100	Postductal	12 infants received CPAP with 100% oxygen	35	40–75 range	NA	NA	All vaginal deliveries
Porter et al24	Term	Ohmeda Biox 3700	Preductal or postductal	100% oxygen if poor respiratory effort, central cyanosis, or heart rate <100. Number receiving oxygen not indicated	96	77 (11)‡	84 (7)‡	89 (6)‡	C/S and vaginal deliveries
Rao and Ramji16	Term and preterm	Novametrix 515A	Preductal	Infants with asphyxia randomised to receive air or 100% oxygen during resuscitation	95	45 (20)‡	84 (14)‡	91 (10)‡	Infants with asphyxia enrolled in the Resair 2 study
				Not reported	30	70 (16)‡	89 (9)‡	94 (2)‡	Non‐asphyxiated controls
Dimich et al5	Not reported	Ohmeda Biox 3700	Preductal	7 infants received 100% supplemental oxygen	100	72 (6)‡	83 (4)‡	91 (5)‡	63 vaginal deliveries 37 C/S
			Postductal			63 (4)‡	77 (4)‡	87 (6)‡

CPAP, continuous positive airway pressure; C/S, caesarean section; NA, not available; SpO₂, saturation by pulse oximetry.

*Mean; †mean (SEM); ‡mean (SD).