The impact of endometrial injury on reproductive outcomes: results of an updated meta-analysis

Good practice recommendations on add-ons in reproductive medicine†

STUDY QUESTION

Which add-ons are safe and effective to be used in ART treatment?

SUMMARY ANSWER

Forty-two recommendations were formulated on the use of add-ons in the diagnosis of fertility problems, the IVF laboratory and clinical management of IVF treatment.

WHAT IS KNOWN ALREADY

The innovative nature of ART combined with the extremely high motivation of the patients has opened the door to the wide application of what has become known as 'add-ons' in reproductive medicine. These supplementary options are available to patients in addition to standard fertility procedures, typically incurring an additional cost. A diverse array of supplementary options is made available, encompassing tests, drugs, equipment, complementary or alternative therapies, laboratory procedures, and surgical interventions. These options share the common aim of stating to enhance pregnancy or live birth rates, mitigate the risk of miscarriage, or expedite the time to achieving pregnancy.

STUDY DESIGN, SIZE, DURATION

ESHRE aimed to develop clinically relevant and evidence-based recommendations focusing on the safety and efficacy of add-ons currently used in fertility procedures in order to improve the quality of care for patients with infertility.

PARTICIPANTS/MATERIALS, SETTING, METHODS

ESHRE appointed a European multidisciplinary working group consisting of practising clinicians, embryologists, and researchers who have demonstrated leadership and expertise in the care and research of infertility. Patient representatives were included in the working group. To ensure that the guidelines are evidence-based, the literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, recommendations were based on the professional experience and consensus of the working group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 46 independent international reviewers. A total of 272 comments were received and incorporated where relevant.

MAIN RESULTS AND THE ROLE OF CHANCE

The multidisciplinary working group formulated 42 recommendations in three sections; diagnosis and diagnostic tests, laboratory tests and interventions, and clinical management.

LIMITATIONS, REASONS FOR CAUTION

Of the 42 recommendations, none could be based on high-quality evidence and only four could be based on moderate-quality evidence, implicating that 95% of the recommendations are supported only by low-quality randomized controlled trials, observational data, professional experience, or consensus of the development group.

WIDER IMPLICATIONS OF THE FINDINGS

These guidelines offer valuable direction for healthcare professionals who are responsible for the care of patients undergoing ART treatment for infertility. Their purpose is to promote safe and effective ART treatment, enabling patients to make informed decisions based on realistic expectations. The guidelines aim to ensure that patients are fully informed about the various treatment options available to them and the likelihood of any additional treatment or test to improve the chance of achieving a live birth.

STUDY FUNDING/COMPETING INTEREST(S)

All costs relating to the development process were covered from ESHRE funds. There was no external funding of the development process or manuscript production. K.L. reports speakers fees from Merck and was part of a research study by Vitrolife (unpaid). T.E. reports consulting fees from Gynemed, speakers fees from Gynemed and is part of the scientific advisory board of Hamilton Thorne. N.P.P. reports grants from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare, speakers fees from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare. S.R.H. declares being managing director of Fertility Europe, a not-for-profit organization receiving financial support from ESHRE. I.S. is a scientific advisor for and has stock options from Alife Health, is co-founder of IVFvision LTD (unpaid) and received speakers' fee from the 2023 ART Young Leader Prestige workshop in China. A.P. reports grants from Gedeon Richter, Ferring Pharmaceuticals and Merck A/S, consulting fees from Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos and Merck A/S, speakers fees from Gedeon Richter, Ferring Pharmaceuticals, Merck A/S, Theramex and Organon, travel fees from Gedeon Richter. The other authors disclosed no conflicts of interest.

DISCLAIMER

This Good Practice Recommendations (GPRs) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation.ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or bedeemedinclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results.Theydo not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type.Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.

Endometrial scratching during hysteroscopy in women undergoing in vitro fertilization: a systematic review and meta-analysis

Objective

Endometrial scratching (ES) during hysteroscopy before embryotransfer (ET) remains doubtable on whether it benefits the reproductive outcomes. The optimal technique is not clear and repeated implantation failure as a challenging field in in vitro fertilization (IVF) seems to be the springboard for clinicians to test its effectiveness.

Methods

Medline, PMC, ScienceDirect, Scopus, CENTRAL, Google Scholar were searched from their inception up to April 2023 for studies to evaluate the effectiveness of adding endometrial scratching during hysteroscopy before ET.

Results

The initial search yielded 959 references, while 12 eligible studies were included in the analyses, involving 2,213 patients. We found that hysteroscopy and concurrent ES before ET resulted in a statistically significant improvement in clinical pregnancy rate (CPR) [RR = 1.50, (95% CI 1.30-1.74), p < 0.0001] and live birth rate (LBR) [RR = 1.67, (95% CI 1.30-2.15), p < 0.0001] with no statistically significant difference on miscarriage rate [RR = 0.80 (95% CI 0.52-1.22), p = 0.30].

Conclusion

Our meta-analysis suggests that hysteroscopy with concurrent ES may be offered in IVF before ET as a potentially improving manipulation. Future randomized trials comparing different patient groups would also provide more precise data on that issue, to clarify specific criteria in the selection of patients.

Systematic Review Registration

PROSPERO (CRD42023414117).

Comparing the effects of endometrial injury in the luteal phase and follicular phase on in vitro fertilization treatment outcomes

BACKGROUND

Several studies have shown that endometrial injury improves clinical pregnancy outcomes in patients undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment with a history of implantation failure. However, endometrial injury can be performed in the follicular phase (FP) followed by embryo transfer in the same menstrual cycle or in the luteal phase (LP) before the embryo transfer cycle.

METHOD

This prospective cohort study was conducted from January 2015 to September 2021, and a total of 487 patients were included. All included patients had a history of a failed implantation cycle. They were divided into two groups: the FP group (N = 330), in which endometrial injury was performed on menstrual day 3-5, and the LP group (N = 157), in which endometrial injury was performed in the cycle preceding embryo transfer 7 days after ovulation.

RESULTS

First, in unselected patients, the implantation rate and clinical pregnancy rate were comparable between the LP and FP groups. However, in patients with a history of ≥ 2 failed transfer cycles, the implantation rate was significantly higher in the LP group than in FP group (43.09% versus 33.33%, P = 0.03). Moreover, the clinical pregnancy rate was also significantly higher in patients in the LP group than in patients in the FP group (60.17% versus 46.15%, P=0.02). In addition, logistic regression analysis showed that endometrial injury in the LP group was an independent factor affecting clinical pregnancy outcome in patients with a history of ≥ 2 failed transfer cycles (aOR = 2.05, 90% CI:1.22-3.47, P=0.01).

CONCLUSION

Endometrial injury improves pregnancy outcomes when performed in the luteal phase compared with the follicular phase in patients with a history of ≥ 2 failed transfer cycles but not in unselected patients.

Intentional endometrial injury enhances angiogenesis through increased production and activation of MMP-9 by TNF-α and MMP-3 in a mouse model

There have been reports of improved pregnancy rates after performing intentional endometrial injuries, also known as endometrial scratching, in patients with recurrent implantation failure. In our previous study on intentional endometrial injury, we found an increased expression of matrix metalloproteinase (MMP)-3 following induced injuries to the mice endometrium. In the current study, we further examine whether the rise in MMP-3 could contribute to increased angiogenesis. Female C57B1/6 mice were obtained at 12 weeks of age, and intentional endometrial injuries were induced mechanically in the left uterine horns. Using the appropriate media, uterine-washes were performed on the injured and uninjured (control) horns of the harvested uteri. The uterine tissues were further processed for tissue lysates, histopathology and immunohistochemistry. The results show that intentional endometrial injuries caused an increase in secreted LPA in the injured horns, which were detected in the uterine-washes. In addition, LPA induced increased production of TNF-α in human endometrial epithelial cells (hEEpCs). Furthermore, TNF-α appeared to induce differential and cell-specific upregulation of the MMPs: MMP-3 was upregulated in the epithelial (hEEpCs), while MMP-9 was upregulated in the endothelial cells (human endometrial endothelial cells; hEEnCs). The upregulation of MMP-3 appeared to be necessary for the activation of MMP-9, whose active form stimulated the formation of vessel-like structure by the hEEnCs. The results of this study suggest that there may be enhanced angiogenesis following intentional endometrial injuries, which is mediated in part by TNF-α-induced and MMP-3-activated MMP-9 production.