Table 2.

Comparison of umbilical artery blood flow between two groups

Groups	Observation group (n=30)	Control group (n=60)	t	P
S/D	4.16±1.46	2.76±0.62	6.398	<0.001
RI	0.74±0.07	0.61±0.09	6.926	<0.001
PI	1.84±0.31	1.07±0.29	11.601	<0.001

Note: S/D: systolic blood flow velocity to end-diastolic blood flow velocity; RI: resistance index; PI: pulsatility index.