Reevaluating the variation of cesarean scar defect

Hiroshi Kobayashi, Imanaka S, Shogo Imanaka
Journal of Obstetrics and Gynaecology Research · 2024 · vol. 50(12) , pp. 2169–2177 · doi:10.1111/jog.16137 · PMID:39497572 · W4404082658
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This review examines the pathogenesis and diverse morphological characteristics of cesarean scar defects, which can involve myometrial disruptions, endometriosis, or adenomyosis, contributing to varying clinical symptoms.

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This narrative review investigates the pathogenesis, morphology, and clinical diversity of cesarean scar defects (CSDs), using electronic database searches to compile 41 relevant publications published up to December 31, 2023. It highlights that the myometrium’s inner and outer layers have distinct origins and functions, and that disruptions across these layers can contribute to CSD development, producing multiple structural manifestations such as myometrial defects, intrauterine cystic protrusions, and extrauterine cystic extensions. The review also reports that symptomatic CSD may be associated histopathologically with uterine scar endometriosis, cystic adenomyosis, or endometrial cysts, implying that CSD—especially cases requiring surgery—may involve iatrogenic endometriosis or adenomyosis, but it does not provide new quantitative estimates or a formal risk stratification within the review. This paper is centrally about endometriosis and adenomyosis in the context of cesarean scar defects — specifically, it summarizes histopathological links between CSD and scar endometriosis or cystic adenomyosis.

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Abstract

AIM: The increasing incidence of cesarean sections has led to a higher prevalence of cesarean scar defects (CSDs), predominantly characterized by postmenstrual bleeding in affected women. CSD manifests in various forms, including isolated myometrial defects, intrauterine cystic protrusions, and extrauterine cystic extensions. The pathophysiological mechanisms underpinning CSD and its associated symptoms remain insufficiently understood. This review explores the pathogenesis of CSD, highlights its morphological characteristics with an emphasis on variable clinical diversity, and addresses the challenges for future research. METHODS: A comprehensive narrative review was conducted using electronic databases, including PubMed and Google Scholar, to identify 41 relevant literatures published up to December 31, 2023. RESULTS: The myometrium comprises two distinct layers-the inner and outer myometrium-with differences in their origin, structure, and function. Disruptions within these layers contribute to CSD development. Histopathologically, symptomatic CSD may be linked to uterine scar endometriosis, cystic adenomyosis, or endometrial cysts, suggesting that CSD, particularly those necessitating surgical intervention, are not limited to myometrial defects but may also involve iatrogenic endometriosis or adenomyosis, thereby exacerbating clinical symptoms. CONCLUSION: This review provides an updated understanding of the histopathological features and classification of CSD, with an emphasis on elucidating its underlying pathogenesis.
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Methods

A comprehensive narrative review was conducted using electronic databases, including PubMed and Google Scholar, to identify 41 relevant literatures published up to December 31, 2023.

Results

The myometrium comprises two distinct layers—the inner and outer myometrium—with differences in their origin, structure, and function. Disruptions within these layers contribute to CSD development. Histopathologically, symptomatic CSD may be linked to uterine scar endometriosis, cystic adenomyosis, or endometrial cysts, suggesting that CSD, particularly those necessitating surgical intervention, are not limited to myometrial defects but may also involve iatrogenic endometriosis or adenomyosis, thereby exacerbating clinical symptoms.

Conclusion

This review provides an updated understanding of the histopathological features and classification of CSD, with an emphasis on elucidating its underlying pathogenesis. CONFLICT OF INTEREST STATEMENT The authors declare no competing interests. DATA AVAILABILITY STATEMENT No new data were created.

References

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endometriosisadenomyosis

MeSH descriptors

Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section Cesarean Section

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