Vol 92, No 10 (2021)
Review paper
Published online: 2021-10-19

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Uterine niche after cesarean section: a review of diagnostic methods

Joanna Budny-Winska1, Michal Pomorski1
Pubmed: 34747000
Ginekol Pol 2021;92(10):726-730.


The consequence of each cesarean section is the uterine scar formation. In some patients, uterine scar after cesarean section heals incompletely and as a result, the uterine niche is formed. Most of the small niches are asymptomatic, but the large cesarean scar niches in nonpregnant women may cause a cesarean scar syndrome, which manifest itself as abnormal uterine bleeding, dysmenorrhea and secondary infertility. Among pregnant women, the presence of large niches may be associated with potentially life-threatening consequences, such as cesarean scar dehiscence and uterine rupture, placenta accreta spectrum disorders, placenta previa, cesarean scar pregnancy. Due to the possibility of dangerous consequences related to the occurrence of a uterine niche, in recent years many studies have focused on the term of cesarean scar niche, its risk factors, diagnostic methods and treatment options. Uterine niche can be examined using two- or three-dimensional transvaginal ultrasonography, as well as two- and three-dimensional sonohysterography, hysterosalpingography, hysteroscopy or magnetic resonance imaging. However, neither of the above diagnostic method is considered as the “gold standard”.
There are no unambiguous guidelines on some aspect concerning the diagnosis of cesarean scar niche.
The aim of this study is to analyze and describe the diagnostic methods of cesarean section niche.

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  1. Pomorski M, Fuchs T, Rosner-Tenerowicz A, et al. Standardized ultrasonographic approach for the assessment of risk factors of incomplete healing of the cesarean section scar in the uterus. Eur J Obstet Gynecol Reprod Biol. 2016; 205: 141–145.
  2. Setubal A, Alves J, Osório F, et al. Treatment for uterine isthmocele, a pouchlike defect at the site of a cesarean section scar. J Minim Invasive Gynecol. 2018; 25(1): 38–46.
  3. Jordans IPM, de Leeuw RA, Stegwee SI, et al. Sonographic examination of uterine niche in non-pregnant women: a modified Delphi procedure. Ultrasound Obstet Gynecol. 2019; 53(1): 107–115.
  4. Vervoort A, Vissers J, Hehenkamp W, et al. The effect of laparoscopic resection of large niches in the uterine caesarean scar on symptoms, ultrasound findings and quality of life: a prospective cohort study. BJOG. 2018; 125(3): 317–325.
  5. Pomorski M, Fuchs T, Rosner-Tenerowicz A, et al. Sonographic evaluation of surgical repair of uterine cesarean scar defects. J Clin Ultrasound. 2017; 45(8): 455–460.
  6. Gubbini G, Centini G, Nascetti D, et al. Surgical hysteroscopic treatment of cesarean-induced isthmocele in restoring fertility: prospective study. J Minim Invasive Gynecol. 2011; 18(2): 234–237.
  7. Silver RM. Abnormal placentation: placenta previa, vasa previa, and placenta accreta. Obstet Gynecol. 2015; 126(3): 654–668.
  8. Clark EAS, Silver RM. Long-term maternal morbidity associated with repeat cesarean delivery. Am J Obstet Gynecol. 2011; 205(6 Suppl): S2–10.
  9. Ludwin A, Martins WP, Ludwin I. Evaluation of uterine niche by three-dimensional sonohysterography and volumetric quantification: techniques and scoring classification system. Ultrasound Obstet Gynecol. 2019; 53(1): 139–143.
  10. Al Naimi A, Wolnicki B, Mouzakiti N, et al. Anatomy of the sonographic post-cesarean uterus. Arch Gynecol Obstet. 2021 [Epub ahead of print].
  11. Bij de Vaate AJM, Brölmann HAM, van der Voet LF, et al. Ultrasound evaluation of the Cesarean scar: relation between a niche and postmenstrual spotting. Ultrasound Obstet Gynecol. 2011; 37(1): 93–99.
  12. Yao M, Wang W, Zhou J, et al. Cesarean section scar diverticulum evaluation by saline contrast-enhanced magnetic resonance imaging: The relationship between variable parameters and longer menstrual bleeding. J Obstet Gynaecol Res. 2017; 43(4): 696–704.
  13. Zimmer M, Pomorski M, Fuchs T, et al. Ultrasonograficzna ocena blizny po cieciu cesarskim w macicy nieciezarnej [Ultrasonographic analysis of cesarean scars features in nonpregnant uterus]. Ginekol Pol. 2007; 78(11): 842–846.
  14. Naji O, Abdallah Y, Bij De Vaate AJ, et al. Standardized approach for imaging and measuring Cesarean section scars using ultrasonography. Ultrasound Obstet Gynecol. 2012; 39(3): 252–259.
  15. Tower AM, Frishman GN. Cesarean scar defects: an underrecognized cause of abnormal uterine bleeding and other gynecologic complications. J Minim Invasive Gynecol. 2013; 20(5): 562–572.
  16. Tulandi T, Cohen A. Emerging manifestations of cesarean scar defect in reproductive-aged women. J Minim Invasive Gynecol. 2016; 23(6): 893–902.
  17. Rasheedy R, Sammour H, Elkholy A, et al. Agreement between transvaginal ultrasound and saline contrast sonohysterography in evaluation of cesarean scar defect. J Gynecol Obstet Hum Reprod. 2019; 48(10): 827–831.
  18. Fabres C, Aviles G, De La Jara C, et al. The cesarean delivery scar pouch: clinical implications and diagnostic correlation between transvaginal sonography and hysteroscopy. J Ultrasound Med. 2003; 22(7): 695–700; quiz 701.
  19. El-Mazny A, Abou-Salem N, El-Khayat W, et al. Diagnostic correlation between sonohysterography and hysteroscopy in the assessment of uterine cavity after cesarean section. Middle East Fertility Society Journal. 2011; 16(1): 72–76.
  20. Alalfy M, Osman OM, Salama S, et al. Evaluation of the cesarean scar niche in women with secondary infertility undergoing ICSI using 2D sonohysterography versus 3D sonohysterography and setting a standard criteria; alalfy simple rules for scar assessment by ultrasound to prevent health problems for women. Int J Womens Health. 2020; 12: 965–974.
  21. Budny-Winska J, Zimmer-Stelmach A, Pomorski M. Two- and three-dimensional transvaginal ultrasound in assessment of the impact of selected obstetric risk factors on cesarean scar niche formation: the case-controlled study. Ginekol Pol. 2021; 92(5): 378–382.
  22. Surapaneni K, Silberzweig JE. Cesarean section scar diverticulum: appearance on hysterosalpingography. AJR Am J Roentgenol. 2008; 190(4): 870–874.
  23. Ahmadi F, Torbati L, Akhbari F, et al. Appearance of uterine scar due to previous cesarean section on hysterosalpingography: various shapes, locations and sizes. Iran J Radiol. 2013; 10(2): 103–110.
  24. Sipahi S, Sasaki K, Miller CE. The minimally invasive approach to the symptomatic isthmocele - what does the literature say? A step-by-step primer on laparoscopic isthmocele - excision and repair. Curr Opin Obstet Gynecol. 2017; 29(4): 257–265.
  25. Marotta ML, Donnez J, Squifflet J, et al. Laparoscopic repair of post-cesarean section uterine scar defects diagnosed in nonpregnant women. J Minim Invasive Gynecol. 2013; 20(3): 386–391.
  26. Raimondo G, Grifone G, Raimondo D, et al. Hysteroscopic treatment of symptomatic cesarean-induced isthmocele: a prospective study. J Minim Invasive Gynecol. 2015; 22(2): 297–301.
  27. Connor ME, Clark J. Unusual Hysteroscopic situations: cesarean niche and retained placental tissue. In: Diagnostic and Operative Hysteroscopy. Cambridge University Press 2020: 196.
  28. Chen YY, Tsai CC, Kung FT, et al. Association between hysteroscopic findings of previous cesarean delivery scar defects and abnormal uterine bleeding. Taiwan J Obstet Gynecol. 2019; 58(4): 541–544.
  29. Shapira M, Mashiach R, Meller N, et al. Clinical success rate of extensive hysteroscopic cesarean scar defect excision and correlation to histologic findings. J Minim Invasive Gynecol. 2020; 27(1): 129–134.
  30. van der Voet LF, Jordans IPM, Brölmann HAM, et al. Changes in the uterine scar during the first year after a caesarean section: a prospective longitudinal study. Gynecol Obstet Invest. 2018; 83(2): 164–170.
  31. Bennich G, Rudnicki M, Wilken-Jensen C, et al. Impact of adding a second layer to a single unlocked closure of a Cesarean uterine incision: randomized controlled trial. Ultrasound Obstet Gynecol. 2016; 47(4): 417–422.
  32. Vervoort AJ, Uittenbogaard LB, Hehenkamp WJK, et al. Why do niches develop in Caesarean uterine scars? Hypotheses on the aetiology of niche development. Hum Reprod. 2015; 30(12): 2695–2702.
  33. Woźniak A, Pyra K, Tinto HR, et al. Ultrasonographic criteria of cesarean scar defect evaluation. J Ultrason. 2018; 18(73): 162–165.
  34. Bij de Vaate AJM, van der Voet LF, Naji O, et al. Prevalence, potential risk factors for development and symptoms related to the presence of uterine niches following Cesarean section: systematic review. Ultrasound Obstet Gynecol. 2014; 43(4): 372–382.