Table 2.

Changes in rapid, tonic, and endurance contraction according to participants general characteristics in univariate analysis

Variables	Group	Rapid contraction		Tonic contraction		Endurance contraction
		Mean ± SD	P	Mean ± SD	P	Mean ± SD	P
Age	≤ 29	37.49 ± 17.70	0.420	26.38c ± 13.27	< 0.001	22.22b ± 11.47	< 0.001
	30–39	37.82 ± 18.64		25.75b ± 13.47		21.55a ± 11.48
	40–49	37.91 ± 18.27		23.81a ± 12.68		20.53a ± 11.77
BMI(kg/m2)	< 18.5a	32.61 ± 15.12	< 0.001	22.80 ± 11.75	< 0.001	19.26 ± 10.19	< 0.001
	18.5–23.9b	36.67 ± 17.68		25.31 ± 12.83		21.23 ± 11.08
	24–27.9c	39.32 ± 18.60		27.06 ± 14.17		22.69 ± 11.96
	≥ 28d	42.26 ± 21.70		28.95 ± 14.50		24.66 ± 12.89
Parity	1	36.98a ± 17.68	< 0.001	25.92 ± 13.38	0.293	21.79 ± 11.52	0.445
	2	38.83b ± 19.05		26.12 ± 13.35		21.85 ± 11.41
	3	39.02b ± 19.48		25.90 ± 13.84		22.09 ± 11.80
	≥ 4	33.63 ± 13.54		22.717 ± 9.67		19.32 ± 8.27
Education	≤ 12	36.89 ± 18.66	0.003	24.45 ± 12.93	< 0.001	20.79 ± 11.08	< 0.001
	> 12	37.85 ± 18.14		26.32 ± 13.45		22.04 ± 11.56
NW	< 4	37.51 ± 18.09	< 0.001	25.86 ± 13.34	< 0.001	21.69 ± 11.44	< 0.001
	≥ 4	40.43 ± 20.36		28.04 ± 13.87		23.93 ± 12.04
NOF	1	37.57 ± 18.21	< 0.001	25.90 ± 13.35	< 0.001	21.74 ± 11.46	< 0.001
	≥ 2	42.74 ± 19.06		29.96 ± 14.22		25.47 ± 12.17
DM	CSd	44.74 ± 18.88	< 0.001	31.23 ± 14.01	< 0.001	26.61 ± 12.09	< 0.001
	NIVDc	34.49 ± 16.85		23.53 ± 12.11		19.55 ± 10.25
	EPb	32.58 ± 15.49		22.48 ± 11.61		18.58 ± 9.84
	FDa	24.29 ± 13.29		16.28 ± 10.44		13.50 ± 8.71

Post-hoc test: a < b < c < d

BMI body mass index, NW neonatal weight, NOF number of fetus, DM delivery mode, CS cesarean section, NIVD non-instrumental vaginal delivery, EP episiotomy, FD forceps delivery