Table 3.

Fetal pulmonary vascular results by ultrasound in baseline conditions and after maternal hyperoxygenation.

	Controls	FGR	p-value*
N	111	97
Gestational age at ultrasound (weeks)	33.0 ± 3.5	33.2 ± 3.5	0.808
Pulmonary Doppler in baseline conditions
Main pulmonary artery
PI	2.24 ± 0.22	2.16 ± 0.27	0.036
Velocity time integral (cm)	10.7 ± 3.5	9.15 ± 1.79	<0.001
Peak systolic velocity (cm/s)	78.5 ± 22.8	68.6 ± 12.4	<0.001
Acceleration time (ms)	41.5 ± 8.2	44.8 ± 12.6	0.026
Ejection time (ms)	191.7 ± 10.2	188.7 ± 11.8	0.053
Acceleration/ejection time ratio	0.22 ± 0.04	0.24 ± 0.06	0.006
Diameter (mm)	5.66 ± 1.16	5.59 ± 1.26	0.978†
Intrapulmonary artery
PI	3.69 ± 1.12	4.22 ± 1.64	0.006
Velocity time integral	7.03 ± 2.02	6.22 ± 2.49	0.011
Peak early-diastolic reverse flow (cm/s)	− 13.9 ± 4.8	− 13.9 ± 5.1	0.988
Pulmonary Doppler after maternal hyperoxygenation
Main pulmonary artery
PI	2.25 ± 0.21	2.16 ± 0.25	0.004
Velocity time integral (cm)	10.5 ± 1.6	9.80 ± 1.70	0.003
Peak systolic velocity (cm/s)	77.2 ± 11.8	71.5 ± 11.9	0.001
Acceleration time (ms)	43.2 ± 7.5	46.2 ± 9.5	0.010
Ejection time (ms)	194.6 ± 11.8	194.3 ± 10.5	0.868
Acceleration/ejection time ratio	0.22 ± 0.04	0.24 ± 0.05	0.007
Diameter (mm)	5.94 ± 1.13	5.68 ± 1.30	0.120†
Intrapulmonary artery
PI	3.47 ± 1.14	3.40 ± 1.11	0.642
Velocity time integral (cm)	8.75 ± 3.11	7.30 ± 2.51	0.287
Peak early-diastolic reverse flow (cm/s)	− 12.5 ± 4.67	− 12.0 ± 3.75	0.425

Data shown as mean ± SD or n (percentage).

PI pulsatility index.

*p-value adjusted by gestational age at ultrasound.

^†p-value adjusted by gestational age at ultrasound and estimated fetal weight.

Statistically significant different (p <0.05) variables are highlighted using bold text.