From: Effect of different delivery modes on the short-term strength of the pelvic floor muscle in Chinese primipara
N
0
1
2
3
4
5
Perineal laceration Group①
398
21
151
192
30
Episiotomy Group②
2279
197
996
975
108
Forceps assisted Group③
72
37
28
①②③
①-②
①-③
②-③
X2 or Z
18.736
−4.182
−2.550
−0.830
p-value
0.000
0.032
1.000