Endometrial scratching to improve pregnancy rate in couples with unexplained subfertility: a randomized controlled trial

The definition of unexplained infertility: A systematic review

BACKGROUND

There is no consensus on tests required to either diagnose unexplained infertility or use for research inclusion criteria. This leads to heterogeneity and bias affecting meta-analysis and best practice advice.

OBJECTIVES

This systematic review analyses the variability of inclusion criteria applied to couples with unexplained infertility. We propose standardised criteria for use both in future research studies and clinical diagnosis.

SEARCH STRATEGY

CINAHL and MEDLINE online databases were searched up to November 2022 for all published studies recruiting couples with unexplained infertility, available in full text in the English language.

DATA COLLECTION AND ANALYSIS

Data were collected in an Excel spreadsheet. Results were analysed per category and methodology or reference range.

MAIN RESULTS

Of 375 relevant studies, only 258 defined their inclusion criteria. The most commonly applied inclusion criteria were semen analysis, tubal patency and assessment of ovulation in 220 (85%), 232 (90%), 205 (79.5%) respectively. Only 87/220 (39.5%) studies reporting semen analysis used the World Health Organization (WHO) limits. Tubal patency was accepted if bilateral in 145/232 (62.5%) and if unilateral in 24/232 (10.3%). Ovulation was assessed using mid-luteal serum progesterone in 115/205 (56.1%) and by a history of regular cycles in 87/205 (42.4%). Other criteria, including uterine cavity assessment and hormone profile, were applied in less than 50% of included studies.

CONCLUSIONS

This review highlights the heterogeneity among studied populations with unexplained infertility. Development and application of internationally accepted criteria will improve the quality of research and future clinical care.

Immune Cell Functionality during Decidualization and Potential Clinical Application

Due to a vast influx in the secretory phase of the menstrual cycle, leukocytes represent 40-50% of the decidua at the time of implantation. Their importance for the implantation, maintenance of pregnancy, and parturition are known yet not fully understood. Thus, in idiopathic infertility, decidual immune-related factors are speculated to be the cause. In this review, the immune cell functions in the decidua were summarized, and clinical diagnostics, as well as interventions, were discussed. There is a rising number of commercially available diagnostic tools. However, the intervention options are still limited and/or poorly studied. In order for us to make big steps towards the proper use of reproductive immunology findings, we need to understand the mechanisms and especially support translational research.

Establishment of reference intervals of endometrial immune cells during the mid-luteal phase

This study aimed to develop reference intervals (RIs) of endometrial immune cells in control infertile women during the mid-luteal phase, and compare with the proportion of endometrial immune cells in recurrent reproductive failure (RRF) patients. Endometrial tissue sections were obtained from 113 fertile women and 79 patients with RRF, including 40 patients who had suffered recurrent miscarriage (RM) and 39 patients with repeated implantation failure (RIF) during the mid-luteal phase of the menstrual cycle. Immunohistochemical staining and quantitative analysis of CD56⁺, Foxp3⁺, CD163⁺, CD1a⁺ and CD8⁺ cells were performed in endometriums. RIs of endometrial immune cells in control infertile women were as follows: CD56⁺ uterine natural killer cells (uNK) cells, 1.785-8.712%, forkhead box P3 (Foxp3)⁺ Tregs, 0.041-0.154%, CD163⁺ M2 macrophages, 0.298-1.492%, CD1a⁺ dendritic cells (DCs), 0.006-0.081% and CD8⁺ T cells, 0.674-2.504%. Compared with control infertile women, the percentage of endometrial CD56⁺ uNK cells, CD163⁺ M2 macrophages, CD1a⁺ DCs and CD8⁺ T cells were significantly increased in patients with RRF. Moreover, Foxp3⁺ Tregs levels were decreased in patients with RRF, and were statistically significant only in patients with RM. In conclusion, the RIs of endometrial immune cells were established in control infertile women during the mid-luteal phase, and a disordered endometrial immune microenvironment was observed in patients with RRF. The RIs of endometrial immune cells may be of important clinical significance for the treatment of RRF.

Endometrial Injury Upregulates Expression of Receptivity Genes in Women with Implantation Failure

BACKGROUND

Homeobox genes A10 (HOXA10) and A11 (HOXA11), members of the abdominal B gene family, are responsible for embryonic survival and implantation. This study was planned to investigate whether endometrial injury alters the expression of both transcripts in women with implantation failure.

METHODS

A total of 54 women with implantation failure were divided into two equal groups as experimental (scratching) and sham (no scratching). Participants in the scratching group were exposed to endometrial injury in the mid-luteal phase, and those in the sham group were exposed to endometrial flushing. The scratching group, but not the sham group, underwent prior endometrial sampling. A second endometrial sampling was performed on the scratching group in the mid-luteal phase of the following cycle. The mRNA and protein levels of the HOXA10 and 11 transcripts were determined in endometrial samples collected before and after injury/flushing. Participants in each group underwent IVF/ET in the cycle after the second endometrial sampling.

RESULTS

Endometrial injury caused a 60.1-fold (p < 0.01) increase in HOXA10 mRNA and a 9.0-fold increase in HOXA11 mRNA (p < 0.02). Injury resulted in a significant increase in both HOXA10 (p < 0.001) and HOXA11 protein expression (p < 0.003). There was no significant change in HOXA10 and 11 mRNA expressions after flushing. Clinical pregnancy, live birth, and miscarriage rates of the both groups were similar.

CONCLUSIONS

Endometrial injury increases homeobox transcript expression at both mRNA and protein levels.

Endometrial injury for pregnancy following sexual intercourse or intrauterine insemination

BACKGROUND

Intentional endometrial injury is being proposed as a technique to improve the probability of pregnancy in women undergoing assisted reproductive technologies (ART) such as in vitro fertilisation (IVF). Endometrial injury is often performed by pipelle biopsy and is a common gynaecological procedure with established safety. However, it causes a moderate degree of discomfort/pain and requires an additional pelvic examination. The effectiveness of this procedure outside of ART, in women or couples attempting to conceive via sexual intercourse or with intrauterine insemination (IUI), remains unclear.

OBJECTIVES

To assess the effectiveness and safety of intentional endometrial injury performed in infertile women or couples attempting to conceive through sexual intercourse or intrauterine insemination (IUI).

SEARCH METHODS

The Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, LILACS, ISI Web of Knowledge, and clinical trial registries were searched from inception to 21 May 2020, as were conference abstracts and reference lists of relevant reviews and included studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated any kind of intentional endometrial injury in women planning to undergo IUI or attempting to conceive spontaneously (with or without ovarian stimulation (OS)) compared to no intervention, a mock intervention, or intentional endometrial injury performed at a different time.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. Primary outcomes were live birth/ongoing pregnancy and pain experienced during the procedure. Due to high risk of bias associated with many of the studies, primary analyses of all review outcomes were restricted to studies at low risk of bias. Sensitivity analysis including all studies was then performed.

MAIN RESULTS

We included 22 RCTs (3703 women). Most of these studies included women with unexplained infertility. Intentional endometrial injury versus either no intervention or a sham procedure The primary analysis was restricted to studies at low risk of bias, which left only one study included. We are uncertain whether endometrial injury has an effect on the probability of live birth, as only one study is included in the analysis and the confidence interval is wide (risk ratio (RR) 1.11, 95% confidence interval (CI) 0.78 to 1.59; 1 RCT, 210 participants). Evidence suggests that if the chance of live birth with no intervention/a sham procedure is assumed to be 34%, then the chance with endometrial injury would be 27% to 55%. When all studies were included in the sensitivity analysis, we were uncertain whether endometrial injury improves live birth/ongoing pregnancy, as the evidence was of very low quality (RR 1.71, 95% CI 1.32 to 2.21; 8 RCTs, 1522 participants; I² = 16%). Evidence suggests that if the chance of live birth/ongoing pregnancy with no intervention/a sham procedure is assumed to be 13%, then the chance with endometrial injury would be 17% to 28%. A narrative synthesis conducted for the other primary outcome of pain during the procedure included studies measuring pain on a zero-to-ten visual analogue scale (VAS) or grading pain as mild/moderate/severe, and showed that most often mild to moderate pain was reported (6 RCTs, 911 participants; very low-quality evidence). Timing of intentional endometrial injury Four trials compared endometrial injury performed in the cycle before IUI to that performed in the same cycle as IUI. None of these studies reported the primary outcomes of live birth/ongoing pregnancy and pain during the procedure. One study compared endometrial injury in the early follicular phase (EFP; Day 2 to 4) to endometrial injury in the late follicular phase (LFP; Day 7 to 9), both in the same cycle as IUI. The primary outcome live birth/ongoing pregnancy was not reported, but the study did report the other primary outcome of pain during the procedure assessed by a zero-to-ten VAS. The average pain score was 3.67 (standard deviation (SD) 0.7) when endometrial injury was performed in the EFP and 3.84 (SD 0.96) when endometrial injury was performed in the LFP. The mean difference was -0.17, suggesting that on average, women undergoing endometrial injury in the EFP scored 0.17 points lower on the VAS as compared to women undergoing endometrial injury in the LFP (95% CI -0.48 to 0.14; 1 RCT, 110 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

Evidence is insufficient to show whether there is a difference in live birth/ongoing pregnancy between endometrial injury and no intervention/a sham procedure in women undergoing IUI or attempting to conceive via sexual intercourse. The pooled results should be interpreted with caution, as the evidence was of low to very low quality due to high risk of bias present in most included studies and an overall low level of precision. Furthermore, studies investigating the effect of timing of endometrial injury did not report the outcome live birth/ongoing pregnancy; therefore no conclusions could be drawn for this outcome. Further well-conducted RCTs that recruit large numbers of participants and minimise bias are required to confirm or refute these findings. Current evidence is insufficient to support routine use of endometrial injury in women undergoing IUI or attempting to conceive via sexual intercourse.

Availability of services for the diagnosis and treatment of infertility in The Gambia`s public and private health facilities: a cross-sectional survey

Background

Infertility is a long-standing reproductive health issue, which affects both men and women worldwide and it is especially problematic in the Global South. In sub-Saharan Africa, understanding the current availability of diagnostic and treatment services for infertility is important because this could guide health systems to improve access to fertility care for all. Yet, few studies have explicitly started from a health system perspective to grasp the availability and integration of infertility services in sub-Saharan Africa. This quantitative study, the first in The Gambia, West Africa, examines the availability of infertility services in public and private facilities as part of a wider endeavour to improve fertility care policy and practice in the country.

Methods

A cross-sectional survey using Qualtrics was administered to 38 health facilities. The survey was carried out between March and August 2021 and involved closed-ended questions. Data analysis consisted of descriptive statistics and t-tests performed using SPSS version 26.

Results

A total of 25 facilities (66%) offered infertility services, of which 13 (52%) were public and 12 (47%) private. Although the availability of screening tests was similar between health institutions, most diagnostic and treatment services were available only in the private sector. Treatment services included: (i) ovarian stimulation (n = 16, 42%); (ii) reversal of tubal ligation and/or blockage (tuboplasty) (n = 4, 11%); and (iii) intrauterine insemination (n = 3, 8%). Assisted reproductive technologies such as IVF and ICSI were not available in public or private sectors. The Gambian health management information system lacked a dedicated space to capture data on infertility. Reported barriers to integration of infertility services in existing reproductive health services included a lack of specialised training, an absence of national guidance on infertility management, and a shortage of appropriate equipment, supplies, and medication.

Conclusions

The availability of infertility services in The Gambia follows a trajectory that is similar to other SSA countries in which services are mostly obtainable through the private sector. Yet, access to private care is expensive and geographically restricted, which exacerbates inequalities in accessing fertility care for all. Improving the provision of infertility services in the public sector requires systematically capturing data on infertility and investing in the provision of a full-range fertility care package.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08514-0.

Impact of endometrial scratching on reproductive outcome in patients: A systematic review and meta-analysis

BACKGROUND

Endometrial scratching (ES) has demonstrated initial success in women with recurrent implantation failure, but the effect in women with 1 previous assisted reproductive technology (ART) failure is unknown. This meta-analysis aimed to evaluate the impact of ES as a treatment in clinical outcomes for women with at least 1 failed in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)/Intrauterine Insemination (IUI).

METHODS

PubMed, Medline, Embase, Cochrane Library, Web of Science, CNKI, and EMCC databases were searched for randomized controlled trial studies utilizing endometrial scratching for infertility women with at least 1 failed assisted reproductive technology (ART) to collect pregnancy outcomes, including clinical pregnancy rate (CPR), embryo implantation rate (IR), miscarriage rate (MR), live birth rate (LBR), and multiple pregnancy rate (MPR).

RESULTS

Sixteen randomized controlled trial (RCT) studies were included in this meta-analysis, including 1770 women in the intervention group and 1934 women in the control group. Overall, the CPR, IR and LBR were significantly higher in the intervention group than in the control group (for CPR, n = 1430, 16 studies, P = .0002, risk ratio (RR) = 1.59, 95% confidence interval [CI] [1.24, 2.03]; for IR, n = 859, 10 studies, P = .0003, RR = 1.67, 95% CI [1.26, 2.21]; for LBR, n = 156, 6 studies, P = .0005, RR = 1.59, 95% CI [1.22, 2.06]). Nonetheless, there was no significant difference in MR (n = 344, 11 studies, P = .62, risk ratio (RR) = 0.92, 95% confidence interval [CI] [0.66, 1.29]) and MPR (n = 98, 3 studies, P = .39, risk ratio (RR) = 0.81, 95% confidence interval [CI] [0.51, 1.30]) between the intervention group and the control group.

CONCLUSION

Endometrial scratching is considered to enhance the reproductive outcomes of embryo implantation. Additional randomized controlled studies are recommended to identify the appropriate time of invasion and the applicable population to confirm whether it can become a routine operation.

Effects of hysterosalpingo-contrast sonography examination on endometrial receptivity among women with unexplained infertility

PURPOSE

Hysterosalpingo-contrast sonography (HyCoSy) is the preferred method for evaluating fallopian tubal patency, and it is associated with improved rates of natural pregnancy among infertile patients. However, the mechanism underlying the improvement in pregnancy rates following HyCoSy remains unclear. This study aimed to investigate the effect of HyCoSy examination on endometrial receptivity as well as pregnancy rates among infertile women.

METHODS

This prospective study included 120 women with unexplained infertility who visited our department between June 2018 and February 2021. These patients were classified into the study group (n = 60) and the control group (n = 60) depending on their willingness to undergo three-dimensional HyCoSy in the present cycle (study group) or 6 months later (control group). Endometrial characteristics, including endometrial thickness and pattern as well as the endometrial blood flow distribution pattern, were measured twice by transvaginal Doppler ultrasonography in the preovulatory phase before and after HyCoSy examination. Participants were followed for 6 months to observe the outcome of spontaneous conception.

RESULTS

Compared with the control group, the study group had a significantly higher cumulative pregnancy rate at 6 months after HyCoSy (21.6% [13/60] vs 5.0% [3/60], P = 0.007). More patients in the study group showed improved endometrial blood flow distribution (P = 0.021, χ² = 7.699), but no differences in endometrial thickness and pattern were observed between the groups (P > 0.05).

CONCLUSION

HyCoSy examination may improve endometrial perfusion and has a therapeutic effect on improving spontaneous pregnancy among women with unexplained infertility.

Lipid metabolism and endometrial receptivity

BACKGROUND

Obesity has now been recognized as a high-risk factor for reproductive health. Although remarkable advancements have been made in ART, a considerable number of infertile obese women still suffer from serial implantation failure, despite the high quality of embryos transferred. Although obesity has long been known to exert various deleterious effects on female fertility, the underlying mechanisms, especially the roles of lipid metabolism in endometrial receptivity, remain largely elusive.

OBJECTIVE AND RATIONALE

This review summarizes current evidence on the impacts of several major lipids and lipid-derived mediators on the embryonic implantation process. Emerging methods for evaluating endometrial receptivity, for example transcriptomic and lipidomic analysis, are also discussed.

SEARCH METHODS

The PubMed and Embase databases were searched using the following keywords: (lipid or fatty acid or prostaglandin or phospholipid or sphingolipid or endocannabinoid or lysophosphatidic acid or cholesterol or progesterone or estrogen or transcriptomic or lipidomic or obesity or dyslipidemia or polycystic ovary syndrome) AND (endometrial receptivity or uterine receptivity or embryo implantation or assisted reproductive technology or in vitro fertilization or embryo transfer). A comprehensive literature search was performed on the roles of lipid-related metabolic pathways in embryo implantation published between January 1970 and March 2022. Only studies with original data and reviews published in English were included in this review. Additional information was obtained from references cited in the articles resulting from the literature search.

OUTCOMES

Recent studies have shown that a fatty acids-related pro-inflammatory response in the embryo-endometrium boundary facilitates pregnancy via mediation of prostaglandin signaling. Phospholipid-derived mediators, for example endocannabinoids, lysophosphatidic acid and sphingosine-1-phosphate, are associated with endometrial receptivity, embryo spacing and decidualization based on evidence from both animal and human studies. Progesterone and estrogen are two cholesterol-derived steroid hormones that synergistically mediate the structural and functional alterations in the uterus ready for blastocyst implantation. Variations in serum cholesterol profiles throughout the menstrual cycle imply a demand for steroidogenesis at the time of window of implantation (WOI). Since 2002, endometrial transcriptomic analysis has been serving as a diagnostic tool for WOI dating. Numerous genes that govern lipid homeostasis have been identified and, based on specific alterations of lipidomic signatures differentially expressed in WOI, lipidomic analysis of endometrial fluid provides a possibility for non-invasive diagnosis of lipids alterations during the WOI.

WIDER IMPLICATIONS

Given that lipid metabolic dysregulation potentially plays a role in infertility, a better understanding of lipid metabolism could have significant clinical implications for the diagnosis and treatment of female reproductive disorders.

Endometrial scratch to increase live birth rates in women undergoing first-time in vitro fertilisation: RCT and systematic review

BACKGROUND

In vitro fertilisation is a widely used reproductive technique that can be undertaken with or without intracytoplasmic sperm injection. The endometrial scratch procedure is an in vitro fertilisation 'add-on' that is sometimes provided prior to the first in vitro fertilisation cycle, but there is a lack of evidence to support its use.

OBJECTIVES

(1) To assess the clinical effectiveness, safety and cost-effectiveness of endometrial scratch compared with treatment as usual in women undergoing their first in vitro fertilisation cycle (the 'Endometrial Scratch Trial') and (2) to undertake a systematic review to combine the results of the Endometrial Scratch Trial with those of previous trials in which endometrial scratch was provided prior to the first in vitro fertilisation cycle.

DESIGN

A pragmatic, multicentre, superiority, open-label, parallel-group, individually randomised controlled trial. Participants were randomised (1 : 1) via a web-based system to receive endometrial scratch or treatment as usual using stratified block randomisation. The systematic review involved searching electronic databases (undertaken in January 2020) and clinicaltrials.gov (undertaken in September 2020) for relevant trials.

SETTING

Sixteen UK fertility units.

PARTICIPANTS

Women aged 18-37 years, inclusive, undergoing their first in vitro fertilisation cycle. The exclusion criteria included severe endometriosis, body mass index ≥ 35 kg/m² and previous trauma to the endometrium.

INTERVENTIONS

Endometrial scratch was undertaken in the mid-luteal phase of the menstrual cycle prior to in vitro fertilisation, and involved inserting a pipelle into the cavity of the uterus and rotating and withdrawing it three or four times. The endometrial scratch group then received usual in vitro fertilisation treatment. The treatment-as-usual group received usual in vitro fertilisation only.

MAIN OUTCOME MEASURES

The primary outcome was live birth after completion of 24 weeks' gestation within 10.5 months of egg collection. Secondary outcomes included implantation, pregnancy, ectopic pregnancy, miscarriage, pain and tolerability of the procedure, adverse events and treatment costs.

RESULTS

One thousand and forty-eight (30.3%) women were randomised to treatment as usual (n = 525) or endometrial scratch (n = 523) and were followed up between July 2016 and October 2019 and included in the intention-to-treat analysis. In the endometrial scratch group, 453 (86.6%) women received the endometrial scratch procedure. A total of 494 (94.1%) women in the treatment-as-usual group and 497 (95.0%) women in the endometrial scratch group underwent in vitro fertilisation. The live birth rate was 37.1% (195/525) in the treatment-as-usual group and 38.6% (202/523) in the endometrial scratch group: an unadjusted absolute difference of 1.5% (95% confidence interval -4.4% to 7.4%; p = 0.621). There were no statistically significant differences in secondary outcomes. Safety events were comparable across groups. No neonatal deaths were recorded. The cost per successful live birth was £11.90 per woman (95% confidence interval -£134 to £127). The pooled results of this trial and of eight similar trials found no evidence of a significant effect of endometrial scratch in increasing live birth rate (odds ratio 1.03, 95% confidence interval 0.87 to 1.22).

LIMITATIONS

A sham endometrial scratch procedure was not undertaken, but it is unlikely that doing so would have influenced the results, as objective fertility outcomes were used. A total of 9.2% of women randomised to receive endometrial scratch did not undergo the procedure, which may have slightly diluted the treatment effect.

CONCLUSIONS

We found no evidence to support the theory that performing endometrial scratch in the mid-luteal phase in women undergoing their first in vitro fertilisation cycle significantly improves live birth rate, although the procedure was well tolerated and safe. We recommend that endometrial scratch is not undertaken in this population.

TRIAL REGISTRATION

This trial is registered as ISRCTN23800982.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 10. See the NIHR Journals Library website for further project information.

Endometrial scratch injury in infertile women seeking conception through natural or intrauterine insemination cycles: A systematic review and meta-analysis

OBJECTIVE

Implantation failure is a major cause of infertility. To evaluate the value of ESI in infertile women undergoing natural or IUI cycles.

METHODS

Screening of MEDLINE, CENTRAL, other bases from inception to June 2021 using the keywords related to endometrial scratch, implantation, infertility, and IUI. RCTs of intentional endometrial injury in couples seeking fertility through natural or IUI cycles were included. All types of ESI with variable intensity (mild to moderate or severe), at different times of the cycle (preceding follicular, preceding luteal, same follicular or two times), single or double compared to none, placebo or other active interventions were included. Twenty-five studies included 4234 women (five natural [774 women], 20 IUI [3460 women]) fulfilled the inclusion criteria. Extracted data included settings of the study, sample size, participant characteristics, intervention details and outcome parameters. The primary outcome was the clinical pregnancy rate.

RESULTS

ESI increased clinical pregnancy rate from 16.1% (62/386) to 26.5% (103/388) and from 11.4% (186/1627) to 22.25% (408/1833), P = 0.004 and <0.001 in natural and IUI cycles, respectively. ESI increased live birth rate from 26.6% (42/158) to 37.6% (59/157) (P = 0.250) and from 11.2% (36/322) to 18% (58/322) (P = 0.020) in natural and IUI cycles, respectively.

CONCLUSION

ESI increased both clinical pregnancy and ongoing pregnancy rates significantly in natural and IUI cycles. However, there is marked methodological heterogeneity among the different studies in defining the outcome parameters.

Endometrial injury for pregnancy following sexual intercourse or intrauterine insemination

BACKGROUND

Intentional endometrial injury is being proposed as a technique to improve the probability of pregnancy in women undergoing assisted reproductive technologies (ART) such as in vitro fertilisation (IVF). Endometrial injury is often performed by pipelle biopsy and is a common gynaecological procedure with established safety. However, it causes a moderate degree of discomfort/pain and requires an additional pelvic examination. The effectiveness of this procedure outside of ART, in women or couples attempting to conceive via sexual intercourse or with intrauterine insemination (IUI), remains unclear.

OBJECTIVES

To assess the effectiveness and safety of intentional endometrial injury performed in infertile women or couples attempting to conceive through sexual intercourse or intrauterine insemination (IUI).

SEARCH METHODS

The Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, LILACS, ISI Web of Knowledge, and clinical trial registries were searched from inception to 21 May 2020, as were conference abstracts and reference lists of relevant reviews and included studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated any kind of intentional endometrial injury in women planning to undergo IUI or attempting to conceive spontaneously (with or without ovarian stimulation (OS)) compared to no intervention, a mock intervention, or intentional endometrial injury performed at a different time or to a higher/lower degree.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. Primary outcomes were live birth/ongoing pregnancy and pain experienced during the procedure. Due to high risk of bias associated with many of the studies, primary analyses of all review outcomes were restricted to studies at low risk of bias. Sensitivity analysis including all studies was then performed.

MAIN RESULTS

We included 23 RCTs (4035 women). Most of these studies included women with unexplained infertility. Intentional endometrial injury versus either no intervention or a sham procedure The primary analysis was restricted to studies at low risk of bias, which left only one study included. We are uncertain whether endometrial injury has an effect on the probability of live birth, as only one study is included in the analysis and the confidence interval is wide (risk ratio (RR) 1.11, 95% confidence interval (CI) 0.78 to 1.59; 1 RCT, 210 participants). Evidence suggests that if the chance of live birth with no intervention/a sham procedure is assumed to be 34%, then the chance with endometrial injury would be 27% to 55%. When all studies were included in the sensitivity analysis, we were uncertain whether endometrial injury improves live birth/ongoing pregnancy, as the evidence was of very low quality (RR 1.71, 95% CI 1.32 to 2.21; 8 RCTs, 1522 participants; I² = 16%). Evidence suggests that if the chance of live birth/ongoing pregnancy with no intervention/a sham procedure is assumed to be 13%, then the chance with endometrial injury would be 17% to 28%. A narrative synthesis conducted for the other primary outcome of pain during the procedure included studies measuring pain on a zero-to-ten visual analogue scale (VAS) or grading pain as mild/moderate/severe, and showed that most often mild to moderate pain was reported (6 RCTs, 911 participants; very low-quality evidence). Higher versus lower degree of intentional endometrial injury Evidence was insufficient to show whether there is a difference in ongoing pregnancy rates (RR 1.29, 95% CI 0.71 to 2.35; 1 RCT, 332 participants; low-quality evidence) between hysteroscopy with endometrial injury and hysteroscopy alone. Evidence suggests that if the chance of ongoing pregnancy with hysteroscopy alone is 10%, then the chance with hysteroscopy with endometrial injury would be 7% to 24%. This study did not report the primary outcomes of live birth and pain during the procedure. Timing of intentional endometrial injury Four trials compared endometrial injury performed in the cycle before IUI to that performed in the same cycle as IUI. None of these studies reported the primary outcomes of live birth/ongoing pregnancy and pain during the procedure. One study compared endometrial injury in the early follicular phase (EFP; Day 2 to 4) to endometrial injury in the late follicular phase (LFP; Day 7 to 9), both in the same cycle as IUI. The primary outcome live birth/ongoing pregnancy was not reported, but the study did report the other primary outcome of pain during the procedure assessed by a zero-to-ten VAS. The average pain score was 3.67 (standard deviation (SD) 0.7) when endometrial injury was performed in the EFP and 3.84 (SD 0.96) when endometrial injury was performed in the LFP. The mean difference was -0.17, suggesting that on average, women undergoing endometrial injury in the EFP scored 0.17 points lower on the VAS as compared to women undergoing endometrial injury in the LFP (95% CI -0.48 to 0.14; 1 RCT, 110 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

Evidence is insufficient to show whether there is a difference in live birth/ongoing pregnancy between endometrial injury and no intervention/a sham procedure in women undergoing IUI or attempting to conceive via sexual intercourse. The pooled results should be interpreted with caution, as the evidence was of low to very low quality due to high risk of bias present in most included studies and an overall low level of precision. Furthermore, studies investigating the effect of timing of endometrial injury did not report the outcome live birth/ongoing pregnancy; therefore no conclusions could be drawn for this outcome. Further well-conducted RCTs that recruit large numbers of participants and minimise bias are required to confirm or refute these findings. Current evidence is insufficient to support routine use of endometrial injury in women undergoing IUI or attempting to conceive via sexual intercourse.

Improving reproductive outcomes of intrauterine insemination: Does endometrial scratch injury help? A randomised controlled trial

OBJECTIVE(S)

Current evidence suggests that endometrial injury improves clinical pregnancy rate while having no effect on miscarriages in women undergoing IVF/ICSI. However, there is no substantial evidence to advocate the use of endometrial injury to benefit the outcomes of IUI treatment. Additionally, there is no clear consensus about the ideal timing, underlying mechanism and optimum intensity of endometrial injury required. The study examines the effect of intentional endometrial injury/scratch in the early proliferative phase of stimulated cycle on reproductive outcomes (clinical and ongoing pregnancy rates and miscarriage occurrence) of intra-uterine insemination treatment (IUI).

STUDY DESIGN, SIZE, DURATION

This prospective, randomized control interventional study was conducted in a tertiary level teaching institution from April 2018 to February 2020. 150 eligible couples requiring IUI treatment who agreed to participate were randomly allocated on 1:1 basis to either control or intervention group. The trial participants received up to 3 cycles ovulation induction with clomiphene citrate and intra-uterine insemination. In addition, women in intervention group were subjected to endometrial scratch injury on day 6-7 of their stimulated cycle. 154 cycles in control arm and 128 cycles in intervention group were analyzed for clinical pregnancy, miscarriages and pain experienced by the women during endometrial scratch injury using the statistical package SPSS (version 21).

RESULT

Similar cumulative clinical pregnancy rates (12.5% Vs 13.6%, RR 1.21, 95% CI 0.44-3.37, p = 0.713), biochemical pregnancy rates (17.1% vs 22.9%, RR 1.43, CI 0.59-3.47, p = 0.421) and ongoing pregnancy rates (10.93% Vs 11.47%, RR 1.05, CI 0.35-3.21, p = 924) were observed in control and intervention arms. Likewise, the relative risk of miscarriage occurrence in the intervention arm was 1.32 (95% CI 0.39-4.32, p = 1.000) which was not statistically different from control group. Mean pain score of 6.93 on numerical pain rating scale was experienced by women whilst having endometrial scratch injury.

CONCLUSIONS

There is insufficient evidence to defend the use of endometrial scratch injury in intra-uterine insemination treatment, as it is moderately painful and have uncertain beneficial influence on reproductive outcomes.

Harmful and beneficial effects of inflammatory response on reproduction: sterile and pathogen-associated inflammation

In reproduction, inflammatory processes play important roles in the development of many pregnancy complications such as preterm labor/birth, recurrent pregnancy loss, recurrent implantation failure, and preeclampsia. Inflammation can be initiated by both microbial and non-microbial causes. Bacterial infection in the feto-maternal interface and uterus can provoke preterm labor/birth, miscarriage, and chronic endometritis. By contrast, inflammation without infection, or 'sterile inflammation,' can also lead to many kinds of complications, such as preterm labor/birth, miscarriage, or preeclampsia. Aberrant inflammation is facilitated by immune cells such as macrophages, dendritic cells, natural killer cells, and invariant natural killer T cells. In addition, cytokines, chemokines, and several kinds of inflammatory mediators are involved. On the other hand, appropriate inflammation is required for a successful offspring during the progression of the entire pregnancy. Herein, we discuss the relation between pregnancy and inflammation with immunological alterations. Understanding the role of inflammation in complications during pregnancy may establish new perspectives of the progress of normal pregnancy as well as treatments during pregnancy complications.

Role of Regulatory T Cells in Regulating Fetal-Maternal Immune Tolerance in Healthy Pregnancies and Reproductive Diseases

Regulatory T cells (Tregs) are a specialized subset of T lymphocytes that function as suppressive immune cells and inhibit various elements of immune response in vitro and in vivo. While there are constraints on the number or function of Tregs which can be exploited to evoke an effective anti-tumor response, sufficient expansion of Tregs is essential for successful organ transplantation and for promoting tolerance of self and foreign antigens. The immune-suppressive property of Tregs equips this T lymphocyte subpopulation with a pivotal role in the establishment and maintenance of maternal tolerance to fetal alloantigens, which is necessary for successful pregnancy. Elevation in the level of pregnancy-related hormones including estrogen, progesterone and human chorionic gonadotropin promotes the recruitment and expansion of Tregs, directly implicating these cells in the regulation of fetal-maternal immune tolerance. Current studies have provided evidence that a defect in the number or function of Tregs contributes to the etiology of several reproductive diseases, such as recurrent spontaneous abortion, endometriosis, and pre-eclampsia. In this review, we provide insight into the underlying mechanism through which Tregs contribute to pregnancy-related immune tolerance and demonstrate the association between deficiencies in Tregs and the development of reproductive diseases.

Effect of endometrial injury during menstruation on clinical outcomes in frozen-thawed embryo transfer cycles: A randomized control trial

Aim

To explore the clinical effect of endometrial injury (EI) on the third day of the menstrual cycle before frozen–thawed embryo transfer (frozen–thawed ET) on patients experienced two or more implantation failures.

Methods

A total of 200 patients who suffered at least two failed hormone‐replacement therapies and frozen–thawed ET were randomly divided into two groups: EI group and control group (n = 100 in each group). Patients in the EI group received local EI with a Pipelle catheter on the third day of the menstrual cycle before frozen–thawed ET. Primary outcomes were live birth, clinical pregnancy and implantation rates. Secondary outcomes were biochemical, multiple and ectopic pregnancy rates and abortion rates.

Results

The rate of live birth in EI group (51.00%) was significantly higher than that of control group (36.00%) (P = 0.032). Clinical pregnancy and implantation rates in EI group were significantly higher comparing to control group (64.00% vs 48.00%, P = 0.023 and 46.74% vs 30.11%, P = 0.001). The rate of multiple pregnancy in EI group (37.50%) was significantly higher than that of control group (18.75%) (P = 0.031). No significant difference in ectopic pregnancy rate and abortion rate was observed between EI group and control group.

Conclusion

Applying EI to patients experienced two or more implantation failures on the third day of the menstrual cycle before frozen–thawed ET can improve clinical outcomes.

Randomised controlled trials evaluating endometrial scratching: assessment of methodological issues

STUDY QUESTION

Do randomised controlled trials (RCTs) evaluating endometrial scratching suffer from methodological issues including insufficient trial registration, statistical errors or irreproducibility, randomisation errors or miscellaneous issues?

SUMMARY ANSWER

The majority of RCTs investigating endometrial scratching have methodological issues.

WHAT IS KNOWN ALREADY

A large number of small RCTs investigating the effectiveness of endometrial scratching prior to in vitro fertilisation (IVF) and intrauterine insemination (IUI)/intercourse have reported favourable findings. Subsequently, systematic reviews incorporating these RCTs yielded meta-analyses in favour of endometrial scratching. Endometrial scratching has been widely adopted by infertility specialists around the world. Recently, an international RCT including 1364 women reported no benefit from endometrial scratching before IVF.

STUDY DESIGN, SIZE, DURATION

We evaluated several methodological issues of RCTs investigating the effectiveness of endometrial scratching prior to IVF and IUI/intercourse. We identified 25 RCTs for IVF and 12 RCTs for IUI/intercourse with full-text publication.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We assessed the RCTs on the following criteria: adequacy of trial registration, statistical issues (description of statistical methods and reproducibility of univariable statistical analysis), excessive similarity or difference in baseline characteristics that is not compatible with chance (Monte Carlo simulations and Kolmogorov–Smirnov test) and miscellaneous methodological issues.

MAIN RESULTS AND THE ROLE OF CHANCE

Of 25 RCTs evaluating endometrial scratching prior to IVF, only eight (32%) had adequate trial registration. In total, 10 (40%) RCTs had issues regarding statistical methods. Nine (69%, 13 applicable) RCTs had at least one inconsistency between reported and reproduced univariable statistical analysis for categorical baseline/intermediate characteristics. Statistical results of at least one outcome were not reproducible in 14 (74%, 19 applicable) RCTs. Only two (8%) RCTs had none of the above issues. Suggested by the simulations, these RCTs did not significantly violate the null hypothesis that the baseline characteristics were the results of a properly conducted randomisation process (P = 0.4395).

Of 12 IUI/intercourse RCTs, only 2 (17%) had adequate trial registration. In total, five (42%) studies had issues of statistical methods. Inconsistency between reported and reproduced univariable analysis for baseline/intermediate categorical variable(s) was found in four (57%, 7 applicable) RCTs. Statistical analysis was not reproducible for at least one outcome in eight (80%, 10 applicable) studies. All RCTs had at least one of the above issues. These RCTs were inconsistent with the null hypothesis that their baseline characteristics were the results of proper randomised allocation (P = 1.659*10−7).

LIMITATIONS, REASONS FOR CAUTION

We were unable to assess RCTs which were not published as full-text papers. We could not analyse individual participant data to investigate possible reasons for statistical inconsistencies. The method to infer the likelihood of proper random sampling rests on assumptions including independent baseline characteristics, simple randomisation and no publication bias.

WIDER IMPLICATIONS OF THE FINDINGS

The methodological issues common to RCTs evaluating endometrial scratching may have biased the results of the trials. Further development and validation of these novel methods may be helpful for the critical appraisal of RCTs.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was sought to support this work. B.W.M. is supported by a National Health Medical Research Council (NHMRC) Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck and Guerbet. D.W. is supported by a grant from the Paracelsus Medical University Salzburg, Austria (PMU Research Fund—PMU FFF Number: L-18/02/006-WET) and by Drs Haackert Foundation, Germany. S.L. is an author of a trial included in this study, an author of an included systematic review and a Cochrane editor. All other authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A

Does endometrial scratching increase the rate of spontaneous conception in couples with unexplained infertility and a good prognosis (Hunault > 30%)? Study protocol of the SCRaTCH-OFO trial: a randomized controlled trial

Background

In the Netherlands, couples with unexplained infertility and a good prognosis to conceive spontaneously (i.e. Hunault > 30%) are advised to perform timed intercourse for at least another 6 months. If couples fail to conceive within this period, they will usually start assisted reproductive technology (ART). However, treatment of unexplained infertility by ART is empirical and can involve significant burdens. Intentional endometrial injury, also called ‘endometrial scratching’, has been proposed to positively affect the chance of embryo implantation in patients undergoing in vitro fertilization (IVF). It might also be beneficial for couples with unexplained infertility as defective endometrial receptivity may play a role in these women. The primary aim of this study is to determine whether endometrial scratching increases live birth rates in women with unexplained infertility.

Method

A multicentre randomized controlled trial will be conducted in Dutch academic and non-academic hospitals starting from November 2017. A total of 792 women with unexplained infertility and a good prognosis for spontaneous conception < 12 months (Hunault > 30%) will be included, of whom half will undergo endometrial scratching in the luteal phase of the natural cycle. The women in the control group will not undergo endometrial scratching. According to Dutch guidelines, both groups will subsequently perform timed intercourse for at least 6 months. The primary endpoint is cumulative live birth rate. Secondary endpoints are clinical and ongoing pregnancy rate; miscarriage rate; biochemical pregnancy loss; multiple pregnancy rate; time to pregnancy; progression to intrauterine insemination (IUI) or IVF; pregnancy complications; complications of endometrial scratching; costs and endometrial tissue parameters associated with reproductive success or failure. The follow-up duration is 12 months.

Discussion

Several small studies show a possible beneficial effect of endometrial scratching in women with unexplained infertility trying to conceive naturally or through IUI. However, the quality of this evidence is very low, making it unclear whether these women will truly benefit from this procedure. The SCRaTCH-OFO trial aims to investigate the effect of endometrial scratching on live birth rate in women with unexplained infertility and a good prognosis for spontaneous conception < 12 months.

Trial registration

NTR6687, registered August 31st, 2017.

Protocol version

Version 2.6, November 14th, 2018.

Recurrent Implantation Failure-update overview on etiology, diagnosis, treatment and future directions

Recurrent implantation failure (RIF) refers to cases in which women have had three failed in vitro fertilization (IVF) attempts with good quality embryos. The definition should also take advanced maternal age and embryo stage into consideration. The failure of embryo implantation can be a consequence of uterine, male, or embryo factors, or the specific type of IVF protocol. These cases should be investigated to determine the most likely etiologies of the condition, as this is a complex problem with several variables. There are multiple risk factors for recurrent implantation failure including advanced maternal age, smoking status of both parents, elevated body mass index, and stress levels. Immunological factors such as cytokine levels and presence of specific autoantibodies should be examined, as well as any infectious organisms in the uterus leading to chronic endometritis. Uterine pathologies such as polyps and myomas as well as congenital anatomical anomalies should be ruled out. Sperm analysis, pre-implantation genetic screening and endometrial receptivity should be considered and evaluated, and IVF protocols should be tailored to specific patients or patient populations. Treatment approaches should be directed toward individual patient cases. In addition, we suggest considering a new initial step in approach to patients with RIF, individualized planned activities to activate the brain's reward system in attempt to improve immunological balance in the body.

Endometrial 'scratching': what the data show

PURPOSE OF REVIEW

Since its first description in 2003, the endometrial scratching procedure has been the topic of over 1000 studies. This procedure, used to improve endometrial receptivity for assisted reproduction, is accessible - any gynecologist can easily perform it - and has been adapted into clinical routine by some reproductive units. However, the available data are controversial, and no biological plausibility exists to support the use of this intervention. This study aims to critically review the existing data, focusing on the last 2 years, regarding the efficiency of endometrial scratching.

RECENT FINDINGS

A total of five randomized controlled studies, one meta-analysis, and a systematic review related to endometrial scratching/injury were published in 2014 and 2015. Considerable heterogeneity exists among these studies regarding the selected population, type of treatment, and even timing and devices used to perform the endometrial injury. Importantly, none of these studies reported improved reproductive outcomes in terms of live birth rates following endometrial scratching.

SUMMARY

Overall, data from properly designed and powered randomized controlled studies demonstrate no beneficial effect of this intervention that is based on unknown biological effects. Endometrial scratching produces pain, costs money, and the side-effects of systematic scratching in the production of Asherman syndrome remain to be seen. Think before scratching.

Endometrial BCL6 testing for the prediction of in vitro fertilization outcomes: a cohort study

OBJECTIVE

To evaluate endometrial BCL6 expression as a prognostic biomarker for IVF outcome in women with unexplained infertility (UI) before ET.

DESIGN

Prospective cohort study.

SETTING

University-associated infertility clinic.

PATIENT(S)

Women with UI for >1 year.

INTERVENTION(S)

We studied women with UI who underwent testing for endometrial BCL6, in an LH-timed midluteal phase biopsy and completed an IVF cycle and ET.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate (PR) and live birth rate per transfer was compared for women positive or negative for BCL6 expression. An abnormal BCL6 result was defined by an histologic score (>1.4).

RESULT(S)

Women with normal and abnormal BCL6 and those who conceived or not had similar characteristics. Women with low levels of BCL6 expression had a significantly higher clinical PR (11/17; 64.7%; 95% confidence interval [CI] 41.3-82.6) compared with women with abnormal (high) BCL6 expression (9/52; 17.3%; 95% CI 9.3-30.8). These results yield a relative risk of 0.267 (95% CI 0.13-0.53; P=.0004) for those with normal BCL6 expression, an absolute benefit of 47.4% (95% CI 22.5-72.0). Live birth rate was also significantly higher in women with low BCL6 expression (10/17; 58.8%; 95% CI 36.0-78.4) compared with women with abnormal BCL6 expression (6/52; 11.5%; 95% CI 5.4-23.0). The relative risk was 0.19 (95% CI 0.08-0.45; P=.0002), yielding an absolute benefit of 47.3% (95% CI 21.8-67.8).

CONCLUSION(S)

Aberrant BCL6 expression (histologic score, >1.4) was strongly associated with poor reproductive outcomes in IVF cycles in women with UI.

Comparison of pregnancy rates between patients with and without local endometrial scratching before intrauterine insemination

OBJECTIVES

To determine the implantation success of local endometrial injury in patients undergoing intrauterine insemination following ovulation induction with gonadotropins as an infertility treatment.

MATERIAL AND METHODS

In this prospective randomized controlled trial, ovulation induction was performed with gonadotropins in 80 patients following intrauterine insemination. In 40 patients, local endometrial injury (scratch) was performed in the midluteal phase of the cycle preceding ovarian stimulation with a Novak curette to the posterior side of the endometrial cavity.

RESULTS

Fifteen pregnancies (37.5%) and 11 clinical pregnancies (27.5%) occurred in the intervention group, whereas eight pregnancies (20%) and five clinical pregnancies (12.5%) occurred in the control group. Although the pregnancy rates and clinical pregnancy rates were increased in the intervention group, no statistically significant difference was found between the intervention and control groups (pregnancy rates: P=0.084; clinical pregnancy rates: P=0.094).

CONCLUSION

Performing local endometrial injury (scratch) in the cycle preceding ovulation induction in patients with a diagnosis of infertility and indication for intrauterine insemination increased the pregnancy and clinical pregnancy rates. This increase was not, however, statistically significant. More randomized, controlled, prospective studies with larger patient numbers are required before the use of iatrogenic induction of local endometrial injury can be recommended in routine clinical practice.

Effect of local endometrial injury in proliferative vs. luteal phase on IVF outcomes in unselected subfertile women undergoing in vitro fertilization

BACKGROUND

Mechanical endometrial injury prior to IVF has been suggested as a means to increase implantation rates by improving endometrial receptivity. However, the effects of endometrial injury in proliferative vs. luteal phase have not been studied before. This study aimed to explore whether endometrial injury in the proliferative phase of the preceding cycle before in vitro fertilization/embryo transfer (IVF-ET) improves the clinical outcomes in unselected subfertile women compared with injury in luteal phase.

METHODS

A group of 142 patients who were good responders to hormonal stimulation were randomized into four groups: injury group (group A: endometrial injury in proliferative phase, n = 38; group B: endometrium injury in luteal phase, n = 32), and non-injury group as control (group C: non-injury in proliferative phase, n = 36; group D: non-injury in luteal phase, n = 36). Patients in injury groups underwent endometrial injury in either proliferative phase or luteal phase in the preceding cycle before IVF treatment. Clinical outcomes including implantation, pregnancy, and live birth rates were analyzed among the four groups.

RESULTS

The baseline characteristics of the four groups including age, body mass index, duration, type and causes of infertility were similar. There were no significant differences in implantation, clinical pregnancy or live birth rates between injury group and non-injury group. Moreover, there were also no significant differences in implantation, clinical pregnancy, or live birth rates in injury in proliferative phase compared with luteal phase.

CONCLUSIONS

Endometrial injury in the cycle preceding IVF of unselected subfertile women does not increase implantation, clinical pregnancy, or live birth rates. Furthermore, there is no significant difference in clinical outcomes between endometrial injury in the proliferative phase and injury in the luteal phase.

TRIAL REGISTRATION

This study was retrospectively registered on May 26th, 2017 (ChiCTR-IOR-17011506).

A randomized trial of local endometrial injury during ovulation induction cycles

OBJECTIVE

To investigate the effect of endometrial injury on pregnancy outcomes among infertile women taking clomifene citrate.

METHODS

A prospective randomized trial was undertaken at an Egyptian hospital between January 26, 2015, and July 17, 2016. Eligible women (≥1 year primary/secondary/unexplained infertility, aged 20-35 years, day-2 follicle-stimulating hormone <12 IU/L, normal prolactin/thyroid function/uterine cavity, ≥1 patent tube, male partner with normal semen count and motility, 3 cycles of clomifene citrate without success) were randomly allocated (1:1) using computer-generated numbers into intervention (received endometrial injury on cycle day 15-24) or control groups (sham procedure). Women began ovulation induction on days 3-5 of the following cycle. Participants and investigators were not masked to group assignment. The primary outcomes were clinical pregnancy, spontaneous abortion, and multiple pregnancy rates. Women who completed follow-up were included in analyses.

RESULTS

The intervention group included 52 women and the control group 53 women. The clinical pregnancy rate was significantly higher in the intervention group (37% [n=19]) than in the control group (13% [n=7]; P=0.006). No differences between the intervention and control groups were noted for spontaneous abortion rate (11% [2/19] vs 29% [2/7]; P=0.287) or multiple pregnancy rate (11% [2/19] vs 14% [1/7]; P=0.790). No adverse effects were reported.

CONCLUSION

Endometrial injury before ovulation induction could improve chances of pregnancy and its outcomes. CLINICALTRIALS.GOV: NCT02345837.

The effect of endometrial scratch injury on pregnancy outcome in women with previous intrauterine insemination failure: A randomized clinical trial

AIM

Endometrial scratch injury (ESI) has been recently proposed to enhance the implantation rate in assisted reproductive technology cycles. The present study was conducted to determine the effect of ESI on pregnancy rate in women with intrauterine insemination (IUI) failure.

METHODS

This prospective randomized controlled study was carried out in Imam-Khomeini Hospital and Royan Institute, Tehran, during a 12-month period from January 2013 to January 2014. After assessment, 169 patients who had IUI failure twice or more (no chemical or clinical pregnancy) with normal uterine anatomy and hysterosalpingography, were enrolled. They were randomly assigned into two groups. In the experimental group, all patients underwent ESI at day 8 or 9 of stimulation phase in the present IUI cycle, whereas no intervention was performed on the control group. IUI outcome was then compared between the two groups.

RESULTS

A total of 150 patients completed the IUI cycle during the study. The chemical pregnancy rate was 10.7% and 2.7% in the experimental and control groups, respectively, without significant difference (P = 0.09). Also no significant differences were detected in terms of clinical pregnancy and miscarriage rates between the two groups (P > 0.05).

CONCLUSIONS

No significant beneficial effect of ESI on fertility outcome in patients with repeated IUI failure was detected when it was carried out on day 8 or 9 of the same IUI stimulation cycle. Also, however, no negative impact secondary to ESI was observed. Therefore, confirmation or refutation of this hypothesis requires further studies with a larger sample size. IRCT201507271141N19.

Introduction: Endometrial function: facts, urban legends, and an eye to the future

The embryo alone, though very important, is not sufficient to explain successful or failed implantation. Human embryonic implantation is less efficient than in nonmenstruating species. The main difference lies in the decidual control of early implantation events and the subsequent course of pregnancy versus embryo control in nonmenstruating species. In this article, we introduce the facts behind the low efficiency of this crucial process, address urban legends routinely considered without high clinical quality evidence, and provide a vision of how the endometrial field will develop in the near future.

Endometrial injury for RIF patients undergoing IVF/ICSI: a prospective nonrandomized controlled trial

To evaluate the effect of endometrial injury on clinical outcomes in subfertile women with repeated implantation failures (RIF) undergoing assisted reproduction. In this prospective nonrandomized controlled trial, 103 subfertile women with RIF were included. Fifty-one underwent endometrial injury through hysteroscopy in the early follicular phase of the previous cycle and 52 underwent the standard protocol without any intervention. Live birth and miscarriage were the primary outcomes. Clinical and in vitro fertilization (IVF) cycle characteristics, were also compared between groups. Both groups were comparable in terms of baseline and cycle characteristics. Live birth rates were significantly higher in the study, compared with the control group (18/51 vs. 8/52, odds ratio (OR) = 0.25; 95% confidence interval (CI) = 0.10-0.64; p = 0.020), although miscarriage rates were similar (7/51 vs. 10/52, OR= 0.25; 95%CI= 0.12-0.66; p = 0.452). The rest of the outcomes parameters were comparable between groups. Logistic regression analysis revealed that endometrial injury and duration of subfertility were independent predictors of live birth after control of other variables (OR = 2.818; 95%CI = 1.044-7.605; p = 0.041 and OR = 0.674; 95%CI = 0.461-0.985, p = 0.042, respectively). Endometrial injury induced through office hysteroscopy in the preceding cycle in subfertile women with RIF improves live birth rates.

Does adding endometrial scratching to diagnostic hysteroscopy improve pregnancy rates in women with recurrent in-vitro fertilization failure?

OBJECTIVE

To investigate the effect of additional endometrial scratching procedure during hysteroscopy on assisted reproductive technology (ART) cycle outcomes in repeated implantation failure (RIF) patients without endometrial or uterine abnormalities on hysteroscopic evaluation.

MATERIALS AND METHODS

Three hundred and forty-five RIF patients who underwent ART at a university-based infertility clinic between January 2011 and June 2015 were recruited in this retrospective cohort study. Uterine cavities of all included patients were evaluated by diagnostic hysteroscopy 7-14 days prior to the subsequent ART cycle. Women without endometrial abnormalities were allocated into two groups; the scratching group was consisted of patients who underwent endometrial scratching by using monopolar electric energy with needle forceps during hysteroscopy, and the control group was consisted of patients who underwent only diagnostic hysteroscopy.

RESULTS

The implantation rate was significantly higher in the scratching group than the control group (37.7% versus 24.5%; p = 0.04). Clinical and ongoing pregnancy rates were also found to be significantly higher in the scratching group than the control group (37.7% versus 27.6%; p = 0.03; and 33.3% versus 23%; p = 0.03, respectively).

CONCLUSION

Endometrial scratching during diagnostic hysteroscopy seems to enhance implantation and as well pregnancy rates in comparison to diagnostic hysteroscopy alone.

Hysteroscopic-guided local endometrial injury does not improve natural cycle pregnancy rate in women with unexplained infertility: Randomized controlled trial

AIM

To evaluate the efficacy of a hysteroscopic site-specific local endometrial injury (LEI) in a group of women with unexplained infertility (UI) undergoing expectant management with no fertility treatment versus no intervention.

METHODS

This open-label, randomized controlled trial (RCT) was conducted between June 2013 and July 2015. Hysteroscopic site-specific LEI was determined by patient identification number, and 120 women were included. Eligible participants were randomly assigned to receive either a single, site-specific LEI guided by hysteroscopy (study group, n = 60) or no intervention (control group, n = 60). Natural cycle folliculometry and timed intercourse were carried out for all participants for 3 months. Successful clinical pregnancy confirmed on ultrasound was the primary outcome measure, and first trimester miscarriage rate was the secondary outcome.

RESULTS

After identification, baseline clinical demographics were similar in the two groups. No statistically significant differences were noted in cumulative pregnancy rates in women with LEI compared with those without (16.7% and 11.7 %, respectively; OR, 2.83; 95%CI: 1.07-7.48; P = 0.4). One first trimester miscarriage was reported in the control group (14.3%).

CONCLUSION

Local endometrial injury for natural cycle conception in women with UI is not justified. Further RCT are warranted to prove or disprove this.

Endometrial injury for pregnancy following sexual intercourse or intrauterine insemination

BACKGROUND

Intentional endometrial injury is currently being proposed as a technique to improve the probability of pregnancy in women undergoing assisted reproductive technologies (ART) such as in vitro fertilisation (IVF). Endometrial injury is often performed by pipelle biopsy or a similar technique, and is a common, simple, gynaecological procedure that has an established safety profile. However, it is also known to be associated with a moderate degree of discomfort/pain and requires an additional pelvic examination. The effectiveness of this procedure outside of ART, in women or couples attempting to conceive via sexual intercourse or with low complexity fertility treatments such as intrauterine insemination (IUI) and ovulation induction (OI), remains unclear.

OBJECTIVES

To evaluate the effectiveness and safety of intentional endometrial injury in subfertile women and couples attempting to conceive through sexual intercourse or intrauterine insemination (IUI).

SEARCH METHODS

We searched the Cochrane Gyanecology and Fertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, CINAHL, LILACS, DARE, ISI Web of Knowledge and ClinicalTrials.gov; as well as reference lists of relevant reviews and included studies. We performed the searches from inception to 31 October 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated any kind of intentional endometrial injury in women planning to undergo IUI or attempting to conceive spontaneously (with or without OI) compared to no intervention, a mock intervention or intentional endometrial injury performed at a different time or to a higher/lower degree.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, extracted data and assessed trial quality using GRADE methodology. The primary outcomes were live birth/ongoing pregnancy and pain experienced during the procedure. Secondary outcomes were clinical pregnancy, miscarriage, ectopic pregnancy, multiple pregnancy and bleeding secondary to the procedure. We combined data to calculate pooled risk ratios (RRs) and 95% confidence intervals (CIs). Statistical heterogeneity was assessed using the I(2) statistic.

MAIN RESULTS

Nine trials, which included a total of 1512 women, met the inclusion criteria of this Cochrane review. Most of these studies included women with unexplained infertility. In seven studies the women were undergoing IUI and in two studies the women were trying to conceive from sexual intercourse. Eight trials compared intentional endometrial injury with no injury/placebo procedure; of these two trials also compared intentional endometrial injury in the cycle prior to IUI with intentional endometrial injury in the IUI cycle. One trial compared higher vs. lower degree of intentional endometrial injury. Intentional endometrial injury vs. either no intervention or a sham procedureWe are uncertain whether endometrial injury improves live birth/ongoing pregnancy as the quality of the evidence has been assessed as very low (risk ratio (RR) 2.22, 95% confidence interval (CI) 1.56 to 3.15; six RCTs, 950 participants; I² statistic = 0%, very low quality evidence). When we restricted the analysis to only studies at low risk of bias the effect was imprecise and the evidence remained of very low quality (RR 2.64, 95% CI 1.03 to 6.82; one RCT, 105 participants; very low quality evidence). Endometrial injury may improve clinical pregnancy rates however the evidence is of low quality (RR 1.98, 95% CI 1.51 to 2.58; eight RCTs, 1180 participants; I² statistic = 0%, low quality evidence).The average pain experienced by participants undergoing endometrial injury was 6/10 on a zero-10 visual analogue scale (VAS)(standard deviation = 1.5). However, only one study reported this outcome. Higher vs. lower degree of intentional endometrial injuryWhen we compared hysteroscopy with endometrial injury to hysteroscopy alone, there was no evidence of a difference in ongoing pregnancy rate (RR 1.29, 95% CI 0.71 to 2.35; one RCT, 332 participants; low quality evidence) or clinical pregnancy rate (RR 1.15, 95% CI 0.66 to 2.01; one RCT, 332 participants, low quality evidence). This study did not report the primary outcome of pain during the procedure. Timing of intentional endometrial injuryWhen endometrial injury was performed in the cycle prior to IUI compared to the same cycle as the IUI, there was no evidence of a difference in ongoing pregnancy rate (RR 0.65, 95% CI 0.37 to 1.16, one RCT, 176 participants; very low quality evidence) or clinical pregnancy rate (RR 0.82, 95% CI 0.50 to 1.36; two RCTs, 276 participants; very low quality evidence). Neither of these studies reported the primary outcome of pain during the procedure.In all three comparisons there was no evidence of an effect on miscarriage, ectopic pregnancy or multiple pregnancy. No studies reported bleeding secondary to the procedure.

AUTHORS' CONCLUSIONS

It is uncertain whether endometrial injury improves the probability of pregnancy and live birth/ongoing pregnancy in women undergoing IUI or attempting to conceive via sexual intercourse. The pooled results should be interpreted with caution as we graded the quality of the evidence as either low or very low. The main reasons we downgraded the quality of the evidence were most included studies were at a high risk of bias and had an overall low level of precision. Further well-conducted RCTs that recruit large numbers of participants and minimise internal bias are required to confirm or refute these findings.

Pipelle for Pregnancy (PIP): study protocols for three randomised controlled trials

Background

The success rate of infertility treatments remains modest. Endometrial injury has been suggested as an intervention to increase the probability of pregnancy in women undergoing assisted reproductive technologies such as in vitro fertilisation (IVF). The majority of studies and systematic reviews have reported that endometrial injury improves the outcomes of IVF, intrauterine insemination and natural conception; however, the size and quality of the studies are poor. The low quality of the available evidence questions the presence of any real beneficial effect, and the applicability of the intervention in different populations remains unclear.

Methods/design

The PIP trials are three multi-centre, randomised controlled trials designed to test three separate hypotheses: whether endometrial injury increases the probability of live birth in women or couples

1) who are undergoing autologous embryo transfer as part of an IVF cycle (PIP-IVF),

2) with unexplained infertility who are attempting to conceive naturally (PIP-UE) and

3) with subfertility related to polycystic ovarian syndrome (PCOS) who are on ovulation induction medication and attempting to conceive (PIP-PCOS).

Participants will be randomised to either undergo endometrial injury by endometrial pipelle biopsy or to:

• no intervention (PIP-IVF), or

• a sham procedure (PIP-PCOS and PIP-UE).

In PIP-IVF, endometrial injury will be carried out between day three of the cycle prior to the IVF cycle, and day three of the IVF cycle. In PIP-UE and PIP-PCOS, endometrial injury or a sham procedure will be undertaken between days 1–12 of a menstrual cycle or ovulation induction cycle respectively. Participants in PIP-UE and PIP-PCOS will then be followed for three cycles during which time they will attempt to conceive from sexual intercourse. To ensure allocation concealment, randomisation will be carried out using a web-based system or sequentially numbered, opaque, sealed envelopes. The primary outcome is live birth. Secondary outcomes include ongoing pregnancy, clinical pregnancy and miscarriage.

The required sample sizes for the PIP studies have been estimated at 840 (PIP-IVF), 350 (PIP-UE) and 280 (PIP-PCOS). Primary analysis will be as per intention-to-treat principles.

Discussion

The PIP trials are designed to address the gaps in the utility of endometrial scratching as a treatment for subfertility in three different populations. If the beneficial effect of this intervention can be confirmed in these settings, endometrial scratching will provide a cost-effective method for helping women and couples to conceive.

Trial registrations

PIP-IVF ACTRN12614000626662 registered 13/6/2014; PIP-PCOS ACTRN12614000657628 registered 24/6/2014; PIP-UE ACTRN12614000656639 registered 24/6/2014. The trials are ongoing.

Endometrial scratching for subfertility: everyone's doing it

STUDY QUESTION

What proportion of clinicians across Australia, New Zealand and the UK are currently offering or recommending endometrial scratching for subfertility?

SUMMARY ANSWER

Eighty-three percent of clinicians responding to this survey are recommending endometrial scratching to women undergoing IVF.

WHAT IS KNOWN ALREADY

Endometrial scratching is currently being proposed as a technique to increase the probability of implantation in women undergoing IVF. While trial results provide evidence in favour of this procedure, there remains some uncertainty about both the extent of any beneficial effect and the subgroups of women most likely to benefit.

STUDY DESIGN, SIZE, DURATION

Cross-sectional survey with responses from a total of 143 public and private fertility care providers surveyed between August and October 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

An online survey was distributed to all 189 fertility clinics across Australia, New Zealand and the UK. All clinicians, nurses and embryologists were eligible to take part. One hundred and forty-three of the 152 responses received were eligible for inclusion, with multiple responses per clinic in 33 cases. At least one response was received from 68 clinics (36% response rate per clinic).

MAIN RESULTS AND THE ROLE OF CHANCE

This survey found that 83% of clinicians commend endometrial scratching prior to IVF. Of these, 92% recommend endometrial scratching to women with recurrent implantation failure (RIF) and 6% recommend it to all women having IVF. Most respondents (73%) agreed that the procedure is beneficial in women with RIF undergoing IVF and disagreed (53%) that the procedure is beneficial for women undergoing their first IVF cycle. The most common timeframe for performing endometrial scratching is the luteal phase of the cycle prior to the IVF cycle. Additionally, only 4% of clinicians recommend endometrial scratching to women undergoing intrauterine insemination or trying to conceive naturally.

LIMITATIONS, REASONS FOR CAUTION

Fertility care providers who recommend endometrial scratching may be more likely to respond to the survey and this could exaggerate the use of the procedure reported here.

WIDER IMPLICATIONS OF THE FINDINGS

This study was conducted across three countries and may be generalizable to similar settings. While this procedure already appears to be offered by the majority of respondents, the results of further studies in this area may further refine or expand the context in which this procedure is beneficial.

STUDY FUNDING/COMPETING INTERESTS

No funding or competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Preovulatory uterine flushing with saline as a treatment for unexplained infertility: a randomised controlled trial protocol

INTRODUCTION

In vitro fertilisation (IVF) is the treatment of choice for unexplained infertility. Preovulatory uterine flushing could reduce intrauterine debris and inflammatory factors preventing pregnancy and constitute an alternative to IVF. Our objective is to assess the efficacy of preovulatory uterine flushing with physiological saline for the treatment of unexplained infertility.

METHODS AND ANALYSIS

We will perform a randomised controlled trial based on consecutive women aged between 18 and 37 years consulting for unexplained infertility for at least 1 year. On the day of their luteinising hormone surge, 192 participants will be randomised in two equal groups to either receive 20 mL of physiological saline by an intrauterine catheter or 10 mL of saline intravaginally. We will assess relative risk of live birth (primary outcome), as well as pregnancy (secondary outcome) over one cycle of treatment. We will report the side effects, complications and acceptability of the intervention.

ETHICS AND DISSEMINATION

This project was approved by the Ethics committee of the Centre Hospitatlier Universitaire de Quebec (no 2015-1146). Uterine flushing is usually well tolerated by women and would constitute a simple, affordable and minimally invasive treatment for unexplained infertility. We plan to communicate the results of the review by presenting research abstracts at conferences and by publishing the results in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT02539290; Pre-results.

RETRACTED: Comparing the effect of office hysteroscopy with endometrial scratch versus office hysteroscopy on intrauterine insemination outcome: a randomized controlled trial

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. The editors were alerted to the possibility of data fabrication in this study by a systematic reviewer who had noticed discrepancies between the trial registry and the published version, and an implausible interval between the date of last recruit and paper submission, given the duration of follow-up. The editors wrote to Dr El-Khayat, who did not give a clear explanation, but kindly supplied a copy of the trial dataset. An independent statistical review of that dataset suggested a high probability that at least some of the data had been fabricated. We shared the comments of our statistical reviewer's analysis with Dr El-Kayat who again failed to give a satisfactory explanation. As suggested by the Committee on Publication Ethics (COPE), the editor-in-chief wrote to the authorities at Cairo University requesting that they investigate. We have not heard back from them. We have therefore decided to retract.

Effect of Endometrial Injury on Secretion of Endometrial Cytokines and IVF Outcomes in Women with Unexplained Subfertility

In order to determine the effect of endometrial injury (EI) on in vitro fertilization (IVF) outcomes in women with unexplained subfertility and explore the relationship between EI and endometrial inflammatory cytokines, 66 women with unexplained subfertility undergoing IVF treatment were recruited. 38 patients in the EI group underwent EI in the mid-luteal phase of the cycle and 28 patients in the non-EI (NEI) group. According to the pregnancy outcome, the NEI and EI groups were divided into NEI-nonpregnant (NEI-NP), NEI-pregnant (NEI-P), EI-NP, and EI-P. All patients underwent aspiration of endometrial secretions immediately before embryo transfer. The concentrations of ten mediators were measured using Milliplex Magnetic Bead assay. The clinical pregnancy was significantly higher in the EI than in the NEI group. The concentrations of interleukin- (IL-) 6, IL-8, IL-12 (p70), IL-13, interferon- (IFN-) γ, monocyte chemotactic protein- (MCP-) 1, and vascular endothelial growth factor (VEGF) were significantly higher in the EI than the NEI group. The expression of IFN-γ and VEGF in the EI-P was significantly increased compared to the EI-NP group. These findings suggest that, in women with unexplained subfertility, endometrial injury might be a potential method to improve clinical pregnancy rates by promoting the expression of IFN-γ and VEGF.

Biopsy-induced inflammatory conditions improve endometrial receptivity: the mechanism of action

A decade ago, we first reported that endometrial biopsy significantly improves the success of pregnancy in IVF patients with recurrent implantation failure, an observation that was later confirmed by others. Recently, we have demonstrated that this treatment elevated the levels of endometrial pro-inflammatory cytokines and increased the abundance of macrophages (Mac) and dendritic cells (DCs). We therefore hypothesised that the biopsy-related successful pregnancy is secondary to an inflammatory response, and aimed at deciphering its mechanism of action. Supporting our hypothesis, we found that the pro-inflammatory TNFα stimulated primary endometrial stromal cells to express cytokines that attracted monocytes and induced their differentiation into DCs. These monocyte-derived DCs stimulated endometrial epithelial cells to express the adhesive molecule SPP1 (osteopontin (OPN)) and its receptors ITGB3 and CD44, whereas MUC16, which interferes with adhesion, was downregulated. Other implantation-associated genes, such as CHST2, CCL4 (MIP1B) and GROA, were upregulated by monocyte-derived Mac. These findings suggest that uterine receptivity is mediated by the expression of molecules associated with inflammation. Such an inflammatory milieu is not generated in some IVF patients with recurrent implantation failure in the absence of local injury provoked by the biopsy treatment.

The role of inflammation for a successful implantation

Approximately half of all human embryo implantations result in failed pregnancy. Multiple factors may contribute to this failure, including genetic or metabolic abnormalities of the embryo. However, many of these spontaneous early abortion cases are attributed to poor uterine receptivity. Furthermore, although many fertility disorders have been overcome by a variety of assisted reproductive techniques, implantation remains the rate-limiting step for the success of the in vitro fertilization (IVF) treatments. We, as well as others, have demonstrated that endometrial biopsies performed either during the spontaneous, preceding cycle, or during the IVF cycle itself, significantly improve the rate of implantation, clinical pregnancies, and live births. These observations suggest that mechanical injury of the endometrium may enhance uterine receptivity by provoking the immune system to generate an inflammatory reaction. In strong support of this idea, we recently found that dendritic cells (DCs), an important cellular component of the innate immune system, play a critical role in successful implantation in a mouse model. In this review, we discuss the hypothesis that the injury-derived inflammation in the biopsy-treated patients generates a focus for uterine DCs and Mac accumulation that, in turn, enhance the endometrial expression of essential molecules that facilitate the interaction between the embryo and the uterine epithelium.

Endometrial scratching performed in the non-transfer cycle and outcome of assisted reproduction: a randomized controlled trial

OBJECTIVES

To investigate the effect of endometrial scratching, performed during oral contraceptive pill (OCP) pretreatment, on reproductive outcome and on ultrasound markers of endometrial receptivity, and to assess the pain involved in the procedure, in unselected women undergoing assisted reproductive techniques (ART).

METHODS

Women undergoing ART were randomly allocated to undergo either endometrial scratching with a pipelle de Cornier or a sham procedure, 7-14 days before starting controlled ovarian stimulation (COS). We evaluated subsequent rates of clinical pregnancy, live birth, implantation, miscarriage and multiple pregnancy. Pain during the procedure was evaluated using a 10-cm visual analog scale. Endometrial thickness and volume and three-dimensional power Doppler (3D-PD) indices (vascularization index (VI), flow index (FI) and vascularization flow index (VFI)) were assessed during COS when there was at least one follicle ≥ 17 mm in diameter.

RESULTS

We included 158 women. Endometrial scratching was associated with higher rates of live birth (41.8% vs 22.8%, P = 0.01) and clinical pregnancy (49.4% vs 29.1%, P = 0.01) and higher pain score (6.42 ± 2.35 cm vs 1.82 ± 1.52 cm, P < 0.001), endometrial VI (3.71 ± 1.77 vs 2.95 ± 1.56, P < 0.01) and VFI (0.97 ± 0.51 vs 0.76 ± 0.40, P < 0.01). There was no significant effect of endometrial scratching on rate of miscarriage (15.4% vs 21.7%, P = 0.53) or multiple pregnancy (22.5% vs 25.0%, P = 0.79), or on endometrial thickness (10.12 ± 1.55 mm vs 9.98 ± 1.62 mm, P = 0.59), endometrial volume (6.18 ± 1.63 cm(3) vs 6.01 ± 1.48 cm(3) , P = 0.51) or FI (26.12 ± 2.82 vs 25.91 ± 2.72, P = 0.65).

CONCLUSIONS

Endometrial scratching performed once, during OCP pretreatment 7-14 days before starting COS, increases the chance of live birth and clinical pregnancy, but might cause considerable pain.