Regarding “Reproductive Outcomes Following Surgical Management for Isthmoceles: A Systematic Review”

Abstract

We have read with great interest the systematic review written by Harjee et al [1Harjee R Khinda J Bedaiwy MA Reproductive outcomes following surgical management for Isthmoceles: a systematic review.J Minim Invasive Gynecol. 2021; 28 (e2): 1291-1302Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar] about reproductive outcomes following surgical management for isthmoceles. We embrace the awareness for long-term effects of cesarean sections, in particular, with respect to the potential detrimental effect of isthmoceles on reproductive outcomes [2Vissers J Sluckin TC van Driel-Delprat CCR et al.Reduced pregnancy and live birth rates after in vitro fertilization in women with previous caesarean section: a retrospective cohort study.Hum Reprod. 2020; 35: 595-604Crossref PubMed Scopus (20) Google Scholar]. However, in our opinion, current available evidence does not allow to draw any conclusions yet on the effectiveness of surgical management of isthmoceles on fertility outcomes. In addition, we believe that the algorithm, as proposed by the authors, should not be advocated as long as it is not supported by well-designed and well-performed clinical trials. Harjee et al [1Harjee R Khinda J Bedaiwy MA Reproductive outcomes following surgical management for Isthmoceles: a systematic review.J Minim Invasive Gynecol. 2021; 28 (e2): 1291-1302Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar] identified 13 studies describing 234 patients with secondary infertility who underwent surgical management for an isthmocele. Unfortunately, these studies had numerous methodological flaws. First of all, except 1 randomized trial, all included studies had an observational design, inducing high risk of bias. Second, there was a poor description of inclusion and exclusion criteria for the individual studies, and information about fertility background and characteristics of the isthmoceles were mostly lacking. In addition, the choice of surgical technique was rarely motivated. Finally, reproductive outcomes were not the primary outcome in the majority of the studies, and none of the studies were powered to evaluate reproductive outcomes. Despite these limitations and the very small sample sizes, the authors concluded that the surgical treatment of isthmoceles, particularly through hysteroscopy in patients with a residual myometrium of at least 2.5 mm, may be effective in treating isthmocele-associated subfertility. Besides our doubts about the validness of this conclusion in the lack of adequate randomized controlled trials, we also have some concerns about the safety of a hysteroscopic niche resection in women with a future wish to conceive. A hysteroscopic approach essentially leads to an enlarged uterine defect, which, in theory, may lead to an increased risk of adverse outcomes such as cesarean scar pregnancy, cervical incompetence, or uterine rupture. Contrarily, the laparoscopic approach aims at the repair of uterine anatomy, plausibly facilitating conception and minimizing the risk of complications in late pregnancy, and might therefore turn out to be the superior technique [3Vissers J Hehenkamp W Lambalk CB Huirne JA Post-caesarean section niche-related impaired fertility: hypothetical mechanisms.Hum Reprod. 2020; 35: 1484-1494Crossref PubMed Scopus (14) Google Scholar,4Donnez O Cesarean scar defects: management of an iatrogenic pathology whose prevalence has dramatically increased.Fertil Steril. 2020; 113: 704-716Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar]. In conclusion, the current systematic review displays the promising results of surgical management for isthmoceles in regard to reproductive outcomes but does not allow to draw solid conclusions about the effectiveness of the different techniques. Future research should focus on both the effectiveness and safety of different surgical approaches, including the additional effect of surgical management on reproductive outcomes in comparison with expectant management. We identified 1 ongoing randomized study in the trial register that is designed to provide answers to the aforementioned topics (NTR 6534). We truly believe that in expectation of the results of such studies, implementation of surgical techniques to improve reproductive outcomes in women with a uterine niche should be suspended [5Nikkels C Vervoort AJMW Mol BW Hehenkamp WJK Huirne JAF Brölmann HAM IDEAL framework in surgical innovation applied on laparoscopic niche repair.Eur J Obstet Gynecol Reprod Biol. 2017; 215: 247-253Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar].