Analysis of Risk Factors for Intraoperative Bleeding in the Surgical Treatment of Cesarean Scar Pregnancy and Development of Predictive Models

Figures & data

Table 1 Comparison of the General Information of the Two Groups

Item	Excessive Bleeding Group (n=27) (Max, Min)	Control Group (n=181) (Max, Min)	P
Age (years)	33.15±5.67 (44,23)	32.97±4.67 (46,22)	0.859
Gravida (number of times)	4.74±1.53 (7,2)	4.66±1.66 (10,2)	0.819
Parity (number of times)	1.63±0.69 (3,1)	1.65±0.57 (3,1)	0.890
Previous cesarean section (number of times)	1.59±0.69 (3,1)	1.55±0.55 (3,1)	0.776
Time since last cesarean section (years)	5.67±3.85 (17,1)	5.87±3.77 (18,0.4)	0.796
Duration of amenorrhea (days)	56.52±13.76 (77,25)	47.41±8.51 (75,29)	0.002**
Maximum diameter of gestational sac (cm)	3.62±1.10 (6,1.2)	2.42±1.08 (5.9,0.5)	<0.001***
Thickness of myometrium at uterine scar site (cm)	0.20±0.10 (0.41,0.05)	0.28±0.15 (0.9,0.09)	0.001**
Preoperative vaginal bleeding (cm)	14.63±14.74 (50,0)	14.59±46.49 (600,0)	0.996
Pre-treatment blood HCG (IU/mL)	79,625.65±68,412.11 (200,000,51.7)	44,600.89±49,243.41 (200,000,145.1)	0.016*
Pre-treatment Hb (g/L)	122.04±18.61 (144,70)	125.59±11.86 (159,81)	0.184
CSP type			0.144
Type I (%)	3 (6.1)	46 (93.9)
Type II (%)	24 (15.1)	135 (84.9)
Blood flow signal grading			<0.001***
Grade 0 (%)	0 (0)	36 (100)
Grade I (%)	1 (1.8)	55 (92.8)
Grade II (%)	4 (10)	36 (90)
Grade III (%)	22 (28.9)	54 (71.1)

Notes: *P < 0.05; **P < 0.01; ***P < 0.001.

Abbreviations: HCG, human chronic gonadotrophin; Hb, hemoglobin; CSP, cesarean scar pregnancy.

Table 2 Results of ROC Curve Analysis of Different Indicators

Item	AUC	P-value	95% CI	Best Cut-Off Value (Sensitivity, Specificity)
Age (years)	0.502	0.970	0.370–0.635	(0.519, 0.652)
Pregnancy history (number of times)	0.523	0.697	0.406–0.640	(0.370, 0.718)
Delivery history (number of times)	0.519	0.753	0.395–0.643	(0.481, 0.597)
Previous cesarean section (number of times)	0.501	0.989	0.376–0.625	(0.111, 0.972)
Time since last cesarean section (years)	0.528	0.645	0.412–0.643	(0.519, 0.635)
Duration of amenorrhea (days)	0.723***	< 0.001	0.605–0.840	(0.704, 0.663)
Maximum diameter of gestational sac (cm)	0.788***	< 0.001	0.697–0.879	(0.741, 0.751)
Thickness of myometrium at uterine scar site (cm)	0.653*	0.010	0.542–0.765	(0.296, 0.956)
Preoperative vaginal bleeding (cm)	0.587	0.147	0.470–0.703	(0.481, 0.713)
Pre-treatment blood HCG (IU/mL)	0.653*	0.012	0.525–0.781	(0.654, 0.722)
Pre-treatment Hb (g/L)	0.522	0.707	0.403–0.642	(0.704, 0.403)

Notes: *P < 0.05; ***P < 0.001.

Abbreviations: ROC, receiver operating characteristic; AUC, the area under the ROC curve; HCG, human chronic gonadotrophin.

Figure 1 Least absolute shrinkage and selection operator (LASSO) regression plot related to bleeding risk. (A) Coefficient path; (B) Cross-validation curve.

Table 3 Multifactorial Logistic Regression Analysis of Predictors Related to Bleeding Risk

Indicator	Coefficient	OR	95% CI	P
Duration of amenorrhea (days)	0.050	1.051	(1.002, 1.102)	0.040*
Maximum diameter of gestational sac (cm)	0.533	1.704	(0.934, 3.108)	0.082
Thickness of myometrium at uterine scar site (cm)	−4.415	0.012	(0.000, 2.329)	0.100
Pre-treatment blood HCG (IU/mL)	0.000	1.000	(1.000, 1.000)	0.576
Blood flow signal grade 0	-	-	-	0.040*
Blood flow signal grade I	−19.848	0.000	(0.000, -)	0.997
Blood flow signal grade II	−2.880	0.056	(0.006, 0.545)	0.013*
Blood flow signal grade III	−1.102	0.332	(0.096, 1.155)	0.083

Note: *P < 0.05.

Abbreviations: OR, odd ratio; CI, confidence interval; HCG, human chronic gonadotrophin.

Figure 2 Bleeding risk prediction nomogram.

Figure 3 Receiver operating characteristic (ROC) curve of the nomogram of bleeding risk prediction.

Figure 4 Calibration curve of the hemorrhage risk prediction nomogram.

Figure 5 Decision curve of the hemorrhagic risk prediction nomogram.