Prevalence, definition, and etiology of cesarean scar defect and treatment of cesarean scar disorder: A narrative review

Abstract

BackgroundCesarean scar defects (CSD) are caused by cesarean sections and cause various symptoms. Although there has been no previous consensus on the name of this condition for a long time, it has been named cesarean scar disorder (CSDi).MethodsThis review summarizes the definition, prevalence, and etiology of CSD, as well as the pathophysiology and treatment of CSDi. We focused on surgical therapy and examined the effects and procedures of laparoscopy, hysteroscopy, and transvaginal surgery.Main findingsThe definition of CSD was proposed as an anechoic lesion with a depth of at least 2 mm because of the varied prevalence, owing to the lack of consensus. CSD incidence depends on the number of times, procedure, and situation of cesarean sections. Histopathological findings in CSD are fibrosis and adenomyosis, and chronic inflammation in the uterine and pelvic cavities decreases fertility in women with CSDi. Although the surgical procedures are not standardized, laparoscopic, hysteroscopic, and transvaginal surgeries are effective.ConclusionThe cause and pathology of CSDi are becoming clear. However, there is variability in the prevalence and treatment strategies. Therefore, it is necessary to conduct further studies using the same definitions.

Cervical Stenosis After Hysteroscopic Surgery for Cesarean Scar Disorder

“…Our patient developed cervical stenosis after TCR for CSDi. Conventionally, when treating CSDi, hysteroscopic surgery is performed when the patient has a sufficient RMT, whereas laparoscopic surgery is performed when the RMT is insufficient [ 1 ]. Although there have been no previous reports of cervical stenosis after hysteroscopic or laparoscopic surgery for CSDi, in this case, cervical stenosis may have been caused by the surgical method used for TCR-CSDi.…”

“…Cesarean scar disorder (CSDi) is a newly recognized disease caused by a cesarean section that has presented various symptoms in recent decades [ 1 ]. Its frequency is estimated to be approximately 18-24% in cesarean section patients [ 1 ], and it is known by various names such as niche, isthmocele, cesarean scar syndrome, and cesarean scar defect [ 2 ]. Recently, a CSDi study group defined CSDi as a cesarean scar defect more than 2 mm deep with one or more primary symptoms or two or more secondary symptoms [ 2 ].…”

“…CSDi can cause abnormal uterine bleeding, chronic pelvic pain, and secondary infertility in women of reproductive age [ 2 - 4 ]. Although the cause of CSDi is not yet elucidated, there are reports describing fibrosis and adenomyosis as the main histopathologic features of cesarean scar defects [ 1 ]. In women who do not intend to become pregnant, treatment options for CSDi include medications such as oral contraceptives or the levonorgestrel-releasing intrauterine system; however, surgery is the only treatment for CSDi patients with infertility [ 1 ].…”

“…Although the cause of CSDi is not yet elucidated, there are reports describing fibrosis and adenomyosis as the main histopathologic features of cesarean scar defects [ 1 ]. In women who do not intend to become pregnant, treatment options for CSDi include medications such as oral contraceptives or the levonorgestrel-releasing intrauterine system; however, surgery is the only treatment for CSDi patients with infertility [ 1 ]. Due to the risk of uterine perforation at thinning scars when performing transcervical resection (TCR) for CSDi, laparoscopic or hysteroscopic surgery is generally chosen for treatment, depending on the residual myometrial thickness (RMT) [ 5 ].…”

“…TCR-CSDi has been reported to increase RMT and reduce symptoms of CSDi [ 1 ]. Previously, three methods of lesion resection for TCR-CSDi have been reported, including (i) resection of only the inferior edge of the defect, (ii) resection of the superior and inferior edges of the defect, and (iii) resection of the bottom of the defect in addition to the superior and inferior edges [ 1 ]. However, the best resection method has not yet been established.…”