Role of relaxin in diastasis of the pubic symphysis peripartum

Table 1 Chi-squared test of delivery modes and delivery durations between the 2 groups

		Delivery modesa		Durationsb
		Cesarean section	Natural labor	1	2	3
Group	Control group	19	20	16	22	1
	Observational group	5	10	10	5	0
Total		24	30	26	27	1

^aχ² = 1.038, P = 0.308.

^bχ² = 3.018, P = 0.221.

Table 2 Comparison of multiple factors between patients with or without diastasis of the pubic symphysis

Variables	Control group	Observational group	t	P value
Relaxin concentration (µg/mL)	170.435 ± 42.299	122.380 ± 0.729	3.245	0.002
Weight of baby (g)	3676.000 ± 521.725	3379.487 ± 402.420	2.229	0.03
Gestational age (wk)	39.809 ± 0.839	39.105 ± 1.258	1.998	0.051
Age at delivery (yr)	29.667 ± 4.271	30.795 ± 4.964	−0.776	0.441
Pre-pregnancy weight	75.467 ± 8.269	76.731 ± 10.807	−0.408	0.685
Weight gain during pregnancy	18.643 ± 2.706	17.716 ± 4.759	0.685	0.497
First stage of labor (min)	359 ± 134.346	374.25 ± 122.553	−0.311	0.758
Second stage of labor (min)	54.70 ± 43.16	45.80 ± 39.325	0.566	0.576

Table 3 Multivariate regression analysis of parturients with pubic symphysis diastasis

	B	Standard error	Wald test quantity	Degrees of freedom	P value	OR
Weight of baby (kg)	0.002	0.001	4.107	1	0.043	1.002
Relaxin concentration (µg/mL)	0.022	0.008	8.075	1	0.004	1.022
	−10.508	3.673	8.183	1	0.004	0.000

OR: Odds ratio.

Table 4 Comparison of multiple factors between pregnant and postpartum parturients in the observational group

	Pregnancy diastasis	Postpartum diastasis	t	P value
Relaxin content (µg/mL)	162.049 ± 43.178	177.774 ± 42.994	-0.705	0.493
Diastatic gap (cm)	1.285 ± 0.458	2.168 ± 1.151	-1.896	0.08
Weight of baby (g)	3807.143 ± 440.519	3561.250 ± 588.058	0.905	0.382
Gestational age (wk)	39.754 ± 0.837	39.858 ± 0.896	-0.229	0.822
Age at delivery (yr)	30 ± 3.559	29.375 ± 5.041	0.273	0.789
Pre-pregnancy weight	78.500 ± 8.646	72.813 ± 7.445	1.370	0.194
Weight gain during pregnancy	18.5 ± 2.345	18.75 ± 3.105	-0.165	0.872
First stage of labor (min)	282.50 ± 173.241	378.13 ± 129.723	-0.890	0.400
Second stage of labor (min)	83.50 ± 94.045	47.50 ± 28.909	1.063	0.319

Table 5 Multivariate linear regression of the degree of diastasis

	Unstandardized coefficient		Standardization coefficient	t	P value	Collinear statistics
	B	Standard error	Beta			Tolerance	Variance inflation factor
Variables	-8.200	29.024		-0.283	0.825
Gestational age (wk)	0.653	0.695	0.477	0.939	0.520	0.361	2.772
Age at delivery (yr)	-0.137	0.111	-0.562	-1.238	0.433	0.451	2.215
Pre-pregnancy weight	-0.077	0.103	-0.601	-0.744	0.593	0.143	7.008
Baby weight (kg)	0.000	0.002	-0.136	-0.170	0.893	0.146	6.859
First stage of labor (min)	-0.001	0.006	-0.150	-0.200	0.874	0.167	6.002
Second stage of labor (min)	0.000	0.010	0.008	0.020	0.987	0.560	1.786
Relaxin content (µg/mL)	0.013	0.014	0.494	0.928	0.524	0.327	3.056
Weight gain during pregnancy	0.366	0.175	-0.938	-2.098	0.283	0.465	2.151

Table 6 Analysis of the correlation between the levels of relaxin and other factors

		Gestational age (wk)	Age at delivery (yr)	Pre-pregnancy weight (kg)	Weight gain during pregnancy (kg)	Neonatal weight (g)	Delivery duration
Relaxin level	Pearson’s correlation coefficient	0.145	0.118	−0.081	0.012	0.002	0.034
	P value	0.301	0.339	0.563	0.931	0.986	0.808

Table 7 Analysis of the correlation between the degree of separation and Barthel index and visual analog scale score

		Barthel index	Visual analog scale
Degree of separation	Pearson’s correlation coefficient	−0.828	0.960
	P value	0.000	0.000