Fantastic niches and where to find them: the current diagnosis and management of uterine niche

Abstract

Background: Caesarean section (CS) scar niche is a well recognised complication of caesarean delivery and is defined as an indentation at the site of the CS scar with a depth of at least 2mm. Objectives: To review systematically the medical literature regarding the current diagnosis and management of uterine niche Materials and Methods: We carried out a systematic review using MeSH terms ‘niche’ OR ‘sacculation’ OR ‘caesarean scar defect’ OR ‘caesarean section scar’ OR ‘uterine defect’ OR ‘isthmocele.’ Articles included were peer-reviewed and in English language. Main Outcome Measures: Prevalence, symptoms, diagnosis, pathophysiology and management of uterine niche. Results: CS scar niche is common and, in a subgroup, produces a range of symptoms including post-menstrual bleeding, dyspareunia and subfertility. It may be linked to use of locked sutures during CS closure. Niche repair can be achieved laparoscopically or hysteroscopically and appears to improve symptoms, although solid conclusions regarding fertility outcomes cannot be drawn. Conclusions: CS scar niche is associated with a range of symptoms. Repair may aid subfertile patients and those with post-menstrual spotting. The presence of a niche is probably irrelevant in the absence of symptoms. What is New? LNG-IUS and surgical repair appear to improve symptoms in those with a niche.

The presentation and management of cesarean scar defects: an updated review on an evolving diagnosis

“…The high incision group had a defect rate of 7%, while in the low incision group, it was 41%, representing a six-fold increased risk of CSD development in the low incision group [51]. Other studies echoed these findings as captured in a recent systematic review [24 ▪ ].…”

“…The hysteroscopic approach traditionally involves resecting the distal and proximal edges of the CSD with fulguration of its base, effectively remodeling the defect to prevent accumulation of menstrual blood in the defect, and facilitate drainage [16,23,24 ▪ ]. Variations include resecting only the inferior edge [32], or additionally resecting the base of the defect when sufficient RMT is present [33,34] (Fig.…”

“…In patients not seeking pregnancy, treatment with combined hormonal contraceptives (CHC) and the levonorgestrel intrauterine system (LNG-IUS) have been used to improve AUB and pain, though evidence is limited to small observational studies [24 ▪ ,25]. Two prospective cohort studies demonstrated a significant reduction in bleeding days for patients with known CSD following 3 months of CHC use.…”

Untersuchung des unteren Uterinsegments im Hinblick auf die Prävalenz einer Nische bei Frauen im Zustand nach Sectio caesarea

“…Diese ist definiert als Einzug des Myometriums im Bereich der ehemaligen Uterotomie um mindestens 2mm 1 . Mögliche Folgen betreffen sowohl schwangere als auch nicht-schwangere Patientinnen, insbesondere steigt das Risiko sowohl für Plazentationsstörungen, ektope (Narben-)Schwangerschaften, Uterusrupturen als auch für Blutungsstörungen, Sterilität und chronische Unterbauschmerzen 2 3 4 . Obwohl uterine Nischen bereits erstmals 1961 beschrieben wurden, sind die genaue Prävalenz (22-84%) und Pathogenese bis heute unklar 5 6 .…”

The Applicability and Effectiveness of Saline Infusion Sonography Using Solid Embryo Transfer Catheter in the Diagnosis of Isthmocele in Patients with Secondary Infertility

“…2 Monteagudo et al defined the term "niche" in 2001, but the condition has also been termed a sacculation, isthmocele, a cesarean/postcesarean scar defect, scar pouch, and pouch-like diverticulum by various authors at the site of cesarean scar in the anterior wall of the lower uterine segment. 3,4 In the year 2019, the "European Niche Taskforce" published a document using the term uterine niche; in which it was defined as an indentation at the site of the cesarean incision with a depth of at least 2 mm. 5 According to Delphi consensus, the niche is subclassified as simple niche, simple niche with one branch, and complex niche.…”