Diagnosing early scar pregnancy in the lower uterine segment after cesarean section by intracavitary ultrasound

Table 1 Early scar pregnancy diagnoses by examination method, n (%)

Method	Cases	Accuracy	Missed diagnosis	Misdiagnosis
Intracavitary	63	61 (96.83)	0 (0.00)	2 (3.17)
Transabdominal	63	53 (84.13)	3 (4.76)	7 (11.11)
χ2 value		4.513	1.366	1.915
P value		0.034	0.242	0.166

Table 2 Examination methods and the diagnostic accuracy for early scar pregnancy types, n (%)

Methods	Cases	Gestational sac	Heterogeneous mass	Uterine cavity	Accuracy
Intracavitary	63	42/42 (100.00)	15/16 (93.75)	4/5 (80.00)	61/63 (96.83)
Transabdominal	63	38/42 (90.48)	12/16 (75.00)	3/5 (60.00)	53/63 (84.13)
χ2 value		2.363	0.948	0.000	4.513
P value		0.124	0.330	1.000	0.034

Table 3 Intracavitary ultrasound for diagnosing early scar pregnancy types

Types	Cases	Performance	Blood flow	Interval (cm)
Gestational sac	42	The gestational sac was located in the scar of the lower uterine segment	Abundant peripheral blood flow	2.42 ± 0.50
Heterogeneous mass	16	The heterogeneous mass was located in the lower part of the anterior wall of uterus, protruding into the bladder	Abundant internal and peripheral blood flow	1.79 ± 0.30
Part of the uterine cavity	5	The gestational sac was located in the lower part of the uterine cavity and part in the scar	Abundant internal and peripheral blood flow	2.29 ± 0.28