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Association of caesarean scar defect with risk of abnormal uterine bleeding: results from meta-analysis
BMC Women's Health volume 24, Article number: 432 (2024)
Abstract
Objective
To investigate the association between caesarean scar defects and abnormal uterine bleeding through systematic literature review.
Methods
PubMed, Web of Science, Cochrane Library and Embase databases were searched based on PRISMA 2020 to include studies exploring abnormal uterine bleeding in women with caesarean scar defects. The combined relative risk (RR) of uterine bleeding, combined prevalence of abnormal uterine bleeding and combined RR of intermenstrual uterine bleeding were calculated using a fixed- or random-effects model.
Results
Ten studies involving 1,183 women with caesarean scar defects met the inclusion criteria for this study. Compared with women without caesarean scar defects, those with caesarean scar defects had a higher risk of abnormal uterine bleeding (RR: 3.22, 95% CI: 1.83–5.66) and intermenstrual bleeding (RR: 2.93, 95% CI: 1.91–4.50). The prevalence of abnormal uterine bleeding was approximately 0.46 (95% CI: 0.27–0.64), and across populations, women with a previous caesarean section who had undergone imaging specifically for gynaecological disease had a significantly higher prevalence of abnormal uterine bleeding (0.77, 95% CI: 0.65–0.89) than those with at least one caesarean Sect. (0.25, 95% CI: 0.10–0.39).
Conclusion
A significant association was observed between caesarean scar defects and abnormal uterine bleeding, with the former being a risk factor for the latter. However, previous studies have differed in the definition of caesarean scar defects and abnormal uterine bleeding, and more high-quality studies are needed to further investigate the relevant definitions and study results in the future.
Introduction
Caesarean section is an effective and important obstetric surgery that can save the lives of both mothers and infants. Epidemiological data show that the caesarean section rate is gradually rising worldwide, approximately doubling since 2000, with a global rate of around 21.7%; this is despite the World Health Organisation’s recommendation that the caesarean section rate should remain around 10% [1,2,3]. In China, the caesarean section rate was as high as 32.7% between 2008 and 2014 [4]. The increasing rate has also led to growing concerns about the long-term complications of caesarean section. After lower segment caesarean section, some patients’ scars at the uterine incision site develop into concave anatomical defects, known as caesarean scar defects or caesarean scar diverticula [5]. Previous studies have shown that caesarean scar defects occur in up to 70% of women undergoing caesarean section, 30% of whom experience symptoms [6].
Over the past few decades, numerous studies have been conducted on caesarean scar defects, which may lead to gynaecological symptoms such as abnormal uterine bleeding [7], pain [8], secondary infertility [9] and asymptomatic uterine rupture [10]. The possible mechanisms of abnormal uterine bleeding associated with caesarean scar defects may include menstrual blood retention in the defect, impaired drainage of fibrous tissue and blood production within the defect due to the presence of neovascularisation, inflammation and adenomyosis [11, 12]. The standard treatment has not yet been established for the management of caesarean scar pregnancy; therefore, establishing an understanding of abnormal uterine bleeding and caesarean scar defects is important to facilitate clinical practice [13]. However, there is a lack of systematic reviews on the risk of abnormal uterine bleeding in women with caesarean scar defects. This study is designed to systematically review the existing literature to determine the relationship between caesarean scar defects and the risk of abnormal uterine bleeding, thus providing an evidence-based reference for clinical practice in this field.
Materials and methods
Retrieval strategy
Following the PRISMA 2020 statement [14], literature was systematically retrieved from four English databases, namely, PubMed, Web of Science, Cochrane Library and Embase, from their inception to November 30, 2023. The retrieval strategies included the following keywords: ‘Cesarean scar’, ‘caesarean scar’, defect’, ‘isthmocele’, ‘Cesarean scar dehiscence’, ‘uterine diverticulum’, ‘niche’, ‘Cesarean scar pouch’, ‘abnormal bleeding’, ‘abnormal uterine bleeding’ and ‘bleeding’. Additionally, targeted articles were obtained by reviewing relevant reviews and references from included studies.
Inclusion and exclusion criteria
The inclusion criteria were as follows: (1) studies published in peer-reviewed journals in English or Chinese; (2) studies involving subjects with caesarean scar defects (defined by the investigators); (3) outcomes of interest, including the risk or prevalence of uterine bleeding, menstrual bleeding or abnormal uterine bleeding; different definitions of abnormal uterine bleeding were allowed, but mainly focused on intermenstrual bleeding, postmenstrual bleeding and unscheduled bleeding; and (4) cross-sectional studies, cohort studies and case-control study designs.
The exclusion criteria included: (1) non-population-based studies; (2) conference articles, case reports, systematic reviews and other non-original studies; (3) insufficient outcome data for data analysis; (4) duplicate publications of the same study; and (5) studies for which full-text articles could not be obtained.
Literature screening and data extraction
Literature screening was performed as per the inclusion and exclusion criteria by two investigators separately, first by reading the titles and abstracts of the articles for initial screening, followed by a full-text reading of articles that met the inclusion criteria. In cases of disagreement between the two investigators, a third investigator was consulted, with a consensus reached upon discussion. Following literature screening, the two investigators independently extracted data using a standardised data extraction form, including publication information, demographic characteristics of the study participants, study time and outcome events.
Quality evaluation
The Newcastle–Ottawa Scale (NOS) [15] was used to evaluate the quality of cohort studies and case-control studies. Eight items were evaluated, including representativeness of the study population, comparability between groups, adequacy of outcome evaluation, sufficiency of follow-up time and completeness of follow-up. The maximum score was 9, with a score of 7 or above indicating high-quality articles and a score of 5 or below indicating low-quality articles. Moreover, the quality of cross-sectional studies was evaluated using the JBI Quality Appraisal Checklist [16], which consists of nine evaluation items, and each item is scored as 1 if the included article meets the criteria. The maximum score is 9.
Statistical analysis methods
Statistical analysis was performed using Stata 16.0 software. The effect size for count data was expressed as relative risk (RR), with the 95% confidence interval (CI) used for estimating the interval range. Heterogeneity was determined using I2 statistics and the Q test: I2 < 50% or P > 0.1 indicated homogeneity among the included articles, and a fixed-effects model was used for analysis; I2 > 50% or P < 0.1 indicated poor homogeneity among the included articles, in which case a random-effects model was used for analysis. For significant heterogeneity, subgroup analyses or sensitivity analyses were conducted to explore the source of heterogeneity. Unless otherwise specified, the significance level was set at 0.05.
Results
Basic characteristics and quality evaluation of included articles
After excluding 1,370 duplicate articles, a preliminary screening of the titles and abstracts of 2,921 articles was conducted, 66 articles were included for full-text review, and finally, 10 articles [11, 17,18,19,20,21,22,23,24,25] met the inclusion criteria for this study. The literature screening workflow is shown in Fig. 1. The eligible articles were published between 2001 and 2021 from countries including the United States, China, Finland, Italy, the Netherlands and Chile. The study designs included cohort studies, case-control studies and cross-sectional studies, involving 1,183 subjects with caesarean scar defects, and there was some variability in the definitions of caesarean scar defects and abnormal uterine bleeding among these studies. The quality evaluation results suggested a high quality of the included articles. See Table 1 for more data on the basic characteristics and quality evaluation results of the included articles.
Risk of abnormal uterine bleeding
Six studies compared the risk of abnormal uterine bleeding in women with/ without caesarean scar defects, involving a sample size of 761 exposed participants and 798 controls. Pooled risks were calculated using a random-effects model based on the heterogeneity evaluation (I2 = 73.3%, P = 0.002). The meta-analysis showed that subjects with caesarean scar defects had a 3.22-fold increased risk of abnormal uterine bleeding (95% CI: 1.83–5.66) compared with the control group, as shown in Fig. 2. Since heterogeneity was observed among the included articles, sensitivity analyses were conducted to identify potential sources of heterogeneity; however, no clear sources were found after excluding the included articles one by one, as shown in Fig. 3.
Prevalence of abnormal uterine bleeding
Data on the prevalence of abnormal uterine bleeding in women with caesarean scar defects were reported in 10 studies, and subgroup analyses were conducted on different subgroups of study populations (women with at least one caesarean section; women with previous caesarean section who underwent imaging specifically for gynaecological diseases) to determine the prevalence of abnormal uterine bleeding in different study populations. The heterogeneity evaluation results indicated heterogeneity among the included articles (I2 = 98.6%, P < 0.001), and a meta-analysis was performed using a random-effects model, which revealed that the prevalence of abnormal uterine bleeding was around 0.46 (95% CI: 0.27–0.64). In the different populations, the prevalence of abnormal uterine bleeding in women undergoing imaging (0.77, 95% CI: 0.65–0.89) was significantly higher than that in women with at least one caesarean Sect. (0.25, 95% CI: 0.10–0.39), as shown in Fig. 4. The sensitivity analysis revealed a prevalence of 0.22–0.69 for abnormal uterine bleeding (see Fig. 5).
Risk of intermenstrual bleeding
Three studies provided data on the risk of intermenstrual bleeding in women with caesarean scar defects. The heterogeneity results indicated no heterogeneity among the included articles, and the pooled effect size was calculated using a fixed-effects model. In addition, the meta-analysis indicated that women with caesarean scar defects were more likely to experience intermenstrual bleeding (RR: 2.93, 95% CI: 1.91–4.50) (see Fig. 6).
Discussion
The association between caesarean scar defects and abnormal uterine bleeding was investigated in this study based on a systematic review and meta-analysis. The study designs of the 10 eligible articles were mainly cohort studies and cross-sectional studies, with a lack of data from prospective studies. However, the findings of our study still provide an evidence-based indication for clinical practice in this field, as well as evidence of causal inference between caesarean scar defects and abnormal uterine bleeding. The study findings suggest that women with caesarean scar defects face a significantly increased risk of abnormal uterine bleeding and intermenstrual bleeding, with caesarean scar defects being a risk factor for abnormal uterine bleeding.
Abnormal uterine bleeding is the most common symptom of caesarean scar defects, with the common bleeding pattern being persistent spotting after regular menstruation, and the total bleeding time per cycle usually lasts for over 10 days. Despite its relatively small volume, the diverticulum can still cause prolonged bleeding. Morris et al. [12] concluded that the inflammatory state of the endometrial tissue covering the diverticulum and local endometrial coagulation disorders are among the causes of abnormal uterine bleeding. The connective tissue at this site can also be replaced by the basal tissue, which may negatively affect contractile haemostasis. Moreover, data about histological case characteristics also provide solid evidence for this hypothesised cause of bleeding, and the most common histopathological features of Cesarina scar defects include fibrosis [26], necrotic tissue [27], endometriosis/adenomyosis [28] and inflammatory infiltration [29].
Regarding a dose-response relationship, there may be a strong relationship between caesarean scar defects and abnormal uterine bleeding. Previous studies have demonstrated that the risk of bleeding may be higher in large-sized defects. Specifically, large-sized caesarean scar defects with a depth of over 50% of the muscular layer (or a residual muscular layer thickness of below 2.2 mm) account for 11–45% of all scar defects, while the probability of abnormal uterine bleeding in defects with a depth of over 50% of the muscular layer is six times higher than that in the population with a depth of below 50% [22]. In addition, previous studies have shown that a residual muscular layer thickness of below 2.15 mm at the scar site is an independent risk factor for total menstrual bleeding time longer than 14 days [30] and that repair surgery for caesarean scar defects can improve bleeding symptoms [31, 32].
The cause of a caesarean scar niche appears to be multifactorial and likely a combination of technical factors (low incision location), anatomical factors (uterine retroflexion) and patient factors (body mass index, smoking, maternal age), which might impair healing [33]. In pregnancy, caesarean scar niches have been associated with placenta accreta spectrum disorder and uterine rupture [34]. It should be noted that the standard treatment of caesarean scar defects still requires further research. Caesarean scar defect is a critical problem, much like other uterine surgeries [35, 36], which can cause poor outcomes; therefore, exploring the relationship between caesarean scar defects and poor outcomes is necessary.
Our study provides updated research to explore the relationship between caesarean scar defects and abnormal uterine bleeding, and the quantitative analysis results provide indications for clinical practice [37]. However, it should be noted that this study comes with some limitations. Firstly, there were variations in the definitions of caesarean scar defects and abnormal uterine bleeding among the included articles, which may be one of the main factors contributing to the heterogeneity among them. Therefore, caution should be exercised when interpreting the findings of this study. Additionally, due to limited information and data from the original studies, the quantitative analysis was only conducted on the risk, prevalence and intermenstrual bleeding risk of abnormal uterine bleeding, without any quantitative analysis of other aspects of abnormal uterine bleeding.
In conclusion, the current study findings indicate a clear association between caesarean scar defects and abnormal uterine bleeding. In light of the limitation of this study regarding varied definitions of abnormal uterine bleeding, an expert consensus should be reached in the future to standardise key definitions in this field to ensure the credibility of the reported results. Furthermore, more high-quality prospective studies are still needed for further in-depth investigations into the association between caesarean scar defects and abnormal uterine bleeding.
Data availability
The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.
References
Wells JC, Wibaek R, Poullas M. Global epidemiology of use of and disparities in caesarean sections. Lancet. 2019;394(10192):24–25. https://doi.org/10.1016/S0140-6736(19)30715-9. Epub 2019 Jul 4. PMID: 31282355.
WHO. Caesarean section rates continue to rise, amid growing inequalities in access. Geneva: World Health Organization; 2023.
WHO. WHO statement on caesarean section rates. Reprod Health Matters. 2015;23:149–50.
Li HT, Luo S, Trasande L, Hellerstein S, Kang C, Li JX, Zhang Y, Liu JM, Blustein J. Geographic Variations and Temporal Trends in cesarean Delivery Rates in China, 2008–2014. JAMA. 2017;317(1):69–76. https://doi.org/10.1001/jama.2016.18663. PMID: 28030701.
Kulshrestha V, Agarwal N, Kachhawa G. Post-caesarean niche (isthmocele) in uterine scar: an update. J Obstet Gynaecol India. 2020;70(6):440–6. https://doi.org/10.1007/s13224-020-01370-0. Epub 2020 Sep 21. PMID: 33417629; PMCID: PMC7758379.
Naji O, Abdallah Y, Bij De Vaate AJ, Smith A, Pexsters A, Stalder C, McIndoe A, Ghaem-Maghami S, Lees C, Brölmann HA, Huirne JA, Timmerman D, Bourne T. Standardized approach for imaging and measuring cesarean section scars using ultrasonography. Ultrasound Obstet Gynecol. 2012;39(3):252-9. https://doi.org/10.1002/uog.10077. PMID: 21858885.
Tulandi T, Cohen A. Emerging Manifestations of cesarean Scar Defect in Reproductive-aged Women. J Minim Invasive Gynecol. 2016 Sep-Oct;23(6):893–902. https://doi.org/10.1016/j.jmig.2016.06.020. Epub 2016 Jul 5. PMID: 27393285.
Tsuji S, Nobuta Y, Hanada T, Takebayashi A, Inatomi A, Takahashi A, Amano T, Murakami T. Prevalence, definition, and etiology of cesarean scar defect and treatment of cesarean scar disorder: a narrative review. Reprod Med Biol. 2023;22(1):e12532. https://doi.org/10.1002/rmb2.12532. PMID: 37577060; PMCID: PMC10412910.
Vissers J, Hehenkamp W, Lambalk CB, Huirne JA. Post-caesarean section niche-related impaired fertility: hypothetical mechanisms. Hum Reprod. 2020;35(7):1484–94. https://doi.org/10.1093/humrep/deaa094. PMID: 32613231; PMCID: PMC7568911.
Giampaolino P, Della Corte L, Venetucci P, D’Antuono F, Morra I, Nappi C, Bifulco G. Treatment of asymptomatic uterine rupture of caesarean scar pregnancy in patient with advanced gestational age: case report. J Obstet Gynaecol. 2018;38(4):571–2. Epub 2017 Oct 23. PMID: 29057686.
Bij de Vaate AJ, Brölmann HA, van der Voet LF, van der Slikke JW, Veersema S, Huirne JA. Ultrasound evaluation of the cesarean scar: relation between a niche and postmenstrual spotting. Ultrasound Obstet Gynecol. 2011;37(1):93 – 9. https://doi.org/10.1002/uog.8864. PMID: 21031351.
Morris H. Surgical pathology of the lower uterine segment caesarean section scar: is the scar a source of clinical symptoms? Int J Gynecol Pathol. 1995;14(1):16–20. https://doi.org/10.1097/00004347-199501000-00004. PMID: 7883420.
Giampaolino P, De Rosa N, Morra I, Bertrando A, Di Spiezio Sardo A, Zizolfi B, Ferrara C, Della Corte L, Bifulco G. Management of cesarean scar pregnancy: a single-Institution Retrospective Review. Biomed Res Int. 2018;2018:6486407. https://doi.org/10.1155/2018/6486407. PMID: 29693012; PMCID: PMC5859871.
Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE, Chou R, Glanville J, Grimshaw JM, Hróbjartsson A, Lalu MM, Li T, Loder EW, Mayo-Wilson E, McDonald S, McGuinness LA, Stewart LA, Thomas J, Tricco AC, Welch VA, Whiting P, Moher D. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021;372:n71. https://doi.org/10.1136/bmj.n71. PMID: 33782057; PMCID: PMC8005924.
Stang A. Critical evaluation of the Newcastle-Ottawa scale for the assessment of the quality of nonrandomized studies in meta-analyses. Eur J Epidemiol. 2010;25(9):603–5. https://doi.org/10.1007/s10654-010-9491-z. Epub 2010 Jul 22. PMID: 20652370.
Munn Z, Moola S, Lisy K, Riitano D, Tufanaru C. Chapter 5: systematic reviews of prevalence and incidence. In: Aromataris E, Munn Z, editors. Editors). JBI Manual for evidence synthesis. JBI; 2020.
Monteagudo A, Carreno C, Timor-Tritsch IE. Saline infusion sonohysterography in nonpregnant women with previous Cesarean delivery: the niche in the scar. J Ultrasound Med. 2001;20(10):1105-15. https://doi.org/10.7863/jum.2001.20.10.1105. PMID: 11587017.
Fabres C, Aviles G, De La Jara C, Escalona J, Muñoz JF, Mackenna A, Fernández C, Zegers-Hochschild F, Fernández E. The Cesarean delivery scar pouch: clinical implications and diagnostic correlation between transvaginal sonography and hysteroscopy. J Ultrasound Med. 2003;22(7):695–700; quiz 701-2. https://doi.org/10.7863/jum.2003.22.7.695. PMID: 12862268.
Menada Valenzano M, Lijoi D, Mistrangelo E, Costantini S, Ragni N. Vaginal ultrasonographic and hysterosonographic evaluation of the low transverse incision after caesarean section: correlation with gynaecological symptoms. Gynecol Obstet Invest. 2006;61(4):216–22. https://doi.org/10.1159/000091497. Epub 2006 Feb 13. PMID: 16479140.
Wang CB, Chiu WW, Lee CY, Sun YL, Lin YH, Tseng CJ. cesarean scar defect: correlation between cesarean section number, defect size, clinical symptoms and uterine position. Ultrasound Obstet Gynecol. 2009;34(1):85 – 9. https://doi.org/10.1002/uog.6405. PMID: 19565535.
Li C, Guo Y, Liu Y, Cheng J, Zhang W. Hysteroscopic and laparoscopic management of uterine defects on previous cesarean delivery scars. J Perinat Med. 2014;42(3):363 – 70. https://doi.org/10.1515/jpm-2013-0081. PMID: 24310769.
van der Voet LF, Bij de Vaate AM, Veersema S, Brölmann HA, Huirne JA. Long-term complications of caesarean section. The niche in the scar: a prospective cohort study on niche prevalence and its relation to abnormal uterine bleeding. BJOG. 2014;121(2):236 – 44. https://doi.org/10.1111/1471-0528.12542. PMID: 24373597.
van der Voet LLF, Limperg T, Veersema S, Timmermans A, Bij de Vaate AMJ, Brölmann HAM, Huirne JAF. Niches after cesarean section in a population seeking hysteroscopic sterilization. Eur J Obstet Gynecol Reprod Biol. 2017;214:104–8. https://doi.org/10.1016/j.ejogrb.2017.05.004. Epub 2017 May 3. PMID: 28505564.
Antila RM, Mäenpää JU, Huhtala HS, Tomás EI, Staff SM. Association of cesarean scar defect with abnormal uterine bleeding: the results of a prospective study. Eur J Obstet Gynecol Reprod Biol. 2020;244:134–40. Epub 2019 Nov 21. PMID: 31785470.
Zhou X, Zhang T, Qiao H, Zhang Y, Wang X. Evaluation of uterine scar healing by transvaginal ultrasound in 607 nonpregnant women with a history of cesarean section. BMC Womens Health. 2021;21(1):199. https://doi.org/10.1186/s12905-021-01337-x. PMID: 33985487; PMCID: PMC8117607.
Florio P, Gubbini G, Marra E, Dores D, Nascetti D, Bruni L, Battista R, Moncini I, Filippeschi M, Petraglia F. A retrospective case-control study comparing hysteroscopic resection versus hormonal modulation in treating menstrual disorders due to isthmocele. Gynecol Endocrinol. 2011;27(6):434-8. https://doi.org/10.3109/09513590.2010.495431. Epub 2011 Jan 4. PMID: 21204608.
Gubbini G, Casadio P, Marra E. Resectoscopic correction of the isthmocele in women with postmenstrual abnormal uterine bleeding and secondary infertility. J Minim Invasive Gynecol. 2008 Mar-Apr;15(2):172-5. https://doi.org/10.1016/j.jmig.2007.10.004. PMID: 18312986.
Donnez O, Donnez J, Orellana R, Dolmans MM. Gynecological and obstetrical outcomes after laparoscopic repair of a cesarean scar defect in a series of 38 women. Fertil Steril. 2017;107(1):289–e2962. https://doi.org/10.1016/j.fertnstert.2016.09.033. Epub 2016 Nov 2. PMID: 27816234.
Gubbini G, Centini G, Nascetti D, Marra E, Moncini I, Bruni L, Petraglia F, Florio P. Surgical hysteroscopic treatment of cesarean-induced isthmocele in restoring fertility: prospective study. J Minim Invasive Gynecol. 2011 Mar-Apr;18(2):234-7. https://doi.org/10.1016/j.jmig.2010.10.011. PMID: 21354070.
Yao M, Wang W, Zhou J, Sun M, Zhu J, Chen P, Wang X. 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. https://doi.org/10.1111/jog.13255. Epub 2017 Feb 6. PMID: 28168867.
He Y, Zhong J, Zhou W, Zeng S, Li H, Yang H, Shan N. Four Surgical Strategies for the Treatment of cesarean Scar Defect: A Systematic Review and Network Meta-analysis. J Minim Invasive Gynecol. 2020 Mar-Apr;27(3):593–602. https://doi.org/10.1016/j.jmig.2019.03.027. Epub 2019 Nov 5. PMID: 31698049.
Sanders AP, Murji A. Hysteroscopic repair of cesarean scar isthmocele. Fertil Steril. 2018;110(3):555–6. https://doi.org/10.1016/j.fertnstert.2018.05.032. PMID: 30098702.
Armstrong F, Mulligan K, Dermott RM, Bartels HC, Carroll S, Robson M, Corcoran S, Parland PM, Brien DO, Brophy D, Brennan DJ. Cesarean scar niche: an evolving concern in clinical practice. Int J Gynaecol Obstet. 2023;161(2):356–66. Epub 2022 Nov 21. PMID: 36317541.
Calì G, Timor-Tritsch IE, Palacios-Jaraquemada J, Monteaugudo A, Buca D, Forlani F, Familiari A, Scambia G, Acharya G, D’Antonio F. Outcome of Cesarean scar pregnancy managed expectantly: systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2018;51(2):169–75. https://doi.org/10.1002/uog.17568. PMID: 28661021.
Riemma G, De Franciscis P, Torella M, Narciso G, La Verde M, Morlando M, Cobellis L, Colacurci N. Reproductive and pregnancy outcomes following embryo transfer in women with previous cesarean section: a systematic review and meta-analysis. Acta Obstet Gynecol Scand. 2021;100(11):1949–60. https://doi.org/10.1111/aogs.14239. Epub 2021 Aug 19. PMID: 34414568.
La Verde M, Cobellis L, Torella M, Morlando M, Riemma G, Schiattarella A, Conte A, Ambrosio D, Colacurci N, De Franciscis P. Is uterine myomectomy a real contraindication to vaginal delivery? Results from a prospective study. J Invest Surg. 2022;35(1):126–31. Epub 2020 Oct 26. PMID: 33100090.
Murji A, Sanders AP, Monteiro I, Haiderbhai S, Matelski J, Walsh C, Abbott JA, Munro MG, Maheux-Lacroix S, International Federation of Gynecology and Obstetrics (FIGO) Committee on Menstrual Disorders and Related Health Impacts. Cesarean scar defects and abnormal uterine bleeding: a systematic review and meta-analysis. Fertil Steril. 2022;118(4):758–66. Epub 2022 Aug 17. PMID: 35985862.
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Study design: Xu XJ, Jia JX, Sang ZQ, Li L. Data acquisition: Xu XJ, Jia JX, Sang ZQ, Li L. Data analysis and interpretation: Xu XJ, Jia JX, Sang ZQ, Li L. Manuscript preparation: Xu XJ, Jia JX, Sang ZQ, Li L. Critical revision of the manuscript for intellectual content: Li L. Manuscript review: Xu XJ, Jia JX, Sang ZQ, Li L. Obtaining financing: None.
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Xu, XJ., Jia, JX., Sang, ZQ. et al. Association of caesarean scar defect with risk of abnormal uterine bleeding: results from meta-analysis. BMC Women's Health 24, 432 (2024). https://doi.org/10.1186/s12905-024-03198-6
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DOI: https://doi.org/10.1186/s12905-024-03198-6