Analgesic Effects, Birth Process, and Prognosis of Pregnant Women in Normal Labor by Epidural Analgesia Using Sufentanil in Combination with Ropivacaine: A Retrospective Cohort Study

Table 3

Comparison of the stage of labor and blood loss between the two groups [ ± s].

Grouping	N	The first stage of labor (min)	The second stage of labor (min)	The third stage of labor (min)	Bleeding volume (ml)
Control group	30	445.81 ± 24.22	50.19 ± 3.66	24.91 ± 2.33	280.95 ± 25.44
Research group	30	430.19 ± 12.45	45.91 ± 4.32	20.91 ± 2.34	265.95 ± 20.52
t value		2.698	4.140	6.634	2.513
value		<0.05	<0.05	<0.05	<0.05