Table 5. Comparison of Mean Duration and Pain Score of the First and Second Stages of Labor in Sufentanil and Fentanyl Groups^a.

Stages of Labor	Duration, min			Pain Score, vas
	S Group	F Group	P Value	S Group	F Group	P Value
First stage	52.45 ± 33.63	46.65 ± 33.40	0.074	1.73 ± 2.10	1.27 ± 2.01	0.294
Second stage	26.51 ± 19.49	26.46 ± 18.52	0.971	2.54 ± 3.06	2.20 ± 2.78	0.699

^aValues are expressed as mean ± SD.