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

Dysregulated miR-124-3p in endometrial epithelial cells reduces endometrial receptivity by altering polarity and adhesion

The endometrium undergoes substantial remodeling in each menstrual cycle to become receptive to an implanting embryo. Abnormal endometrial receptivity is one of the major causes of embryo implantation failure and infertility. MicroRNA-124-3p is elevated in both the serum and endometrial tissue of women with chronic endometritis, a condition associated with infertility. MicroRNA-124-3p also has a role in cell adhesion, a key function during receptivity to allow blastocysts to adhere and implant. In this study, we aimed to determine the function of microRNA-124-3p on endometrial epithelial adhesive capacity during receptivity and effect on embryo implantation. Using a unique inducible, uterine epithelial-specific microRNA overexpression mouse model, we demonstrated that elevated uterine epithelial microRNA-124-3p impaired endometrial receptivity by altering genes associated with cell adhesion and polarity. This resulted in embryo implantation failure. Similarly in a second mouse model, increasing microRNA-124-3p expression only in mouse uterine surface (luminal) epithelium impaired receptivity and led to implantation failure. In humans, we demonstrated that microRNA-124-3p was abnormally increased in the endometrial epithelium of women with unexplained infertility during the receptive window. MicroRNA-124-3p overexpression in primary human endometrial epithelial cells (HEECs) impaired primary human embryo trophectoderm attachment in a 3-dimensional culture model of endometrium. Reduction of microRNA-124-3p in HEECs from infertile women normalized HEEC adhesive capacity. Overexpression of microRNA-124-3p or knockdown of its direct target IQGAP1 reduced fertile HEEC adhesion and its ability to lose polarity. Collectively, our data highlight that microRNA-124-3p and its protein targets contribute to endometrial receptivity by altering cell polarity and adhesion.

Enrichment of cell cycle pathways in progesterone-treated endometrial organoids of infertile women compared to fertile women

PURPOSE

To investigate whether the transcriptome profile differs between progesterone-treated infertile and fertile endometrial organoids.

METHODS

Endometrial biopsies were obtained from 14 infertile and seven fertile women, after which organoids were generated from isolated epithelial cells. To mimic the secretory phase, organoids were sequentially treated with 17β-estradiol (E2) and progesterone (P4) and subjected to RNA sequencing. Differentially expressed genes (DEGs) were identified using DESeq2 (lfcThreshold = 0, log2 Fold Change ≥ 1.0 or ≤ -1.0), and a principal component analysis (PCA) plot was generated. Functional enrichment analysis was performed by overrepresentation analysis and Gene Set Enrichment Analysis (GSEA). To functionally assess proliferation, OrganoSeg surface measurements were performed before (T0) and after (T1) differentiation of organoids, and T1/T0 ratios were calculated to determine the proliferation rate.

RESULTS

Although the PCA plot did not show clear clustering of the fertile and infertile samples, 363 significant DEGs (129 upregulated and 234 downregulated) were detected in infertile compared to fertile organoids. Mainly cell cycle processes were highly enriched in infertile organoids. Thus, we hypothesised that proliferative activity during differentiation may be higher in infertile organoids compared to fertile organoids. However, this could not be validated by cell surface measurements.

CONCLUSIONS

This study revealed that cell cycle processes were enriched in E2/P4-treated infertile endometrial organoids as compared to fertile organoids. This could reflect persistently higher proliferative activity of the endometrial epithelial cells in differentiated infertile organoids compared to fertile organoids. To confirm this hypothesis, further studies are warranted.

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).

Abnormal expression of galectin-1, -3 leading to unexplained infertility by decreasing endometrial receptivity: a retrospective analysis

OBJECTIVE

To explore the relationship between galectin-1, -3 and unexplained infertility and the effect on endometrial receptivity.

METHODS

The clinical data of 100 female patients at childbearing age coming to Xingtai People's Hospital from February 2019 to February 2021 were collected retrospectively. Based on normal pregnancy or not, 50 infertility patients were placed into an infertility group, and 50 patients with normal pregnancy history were placed into a normal group. The mRNA and protein levels of galectin-1, -3, endometrial wave-like activity, endometrial thickness, uterine artery pulsatility index (PI), resistance index (RI), end diastolic velocity (EDV) and peak systolic velocity (PSV) ratio (S/D = PSV/EDV) were compared between the two groups of patients.

RESULTS

The mRNA and protein levels of galectin-1, -3 in the infertile group were lower than those in the normal group (P<0.05). In addition, the endometrial wave-like activity in the infertile group was more than that in the normal group (P<0.05). The endometrial thickness was less, while PI, RI and S/D were higher in the infertile group than those in the normal group (P<0.05).

CONCLUSION

The low mRNA and protein expressions of galectin-1, -3 in unexplained infertility can affect endometrial receptivity, which may be closely related to unexplained infertility.

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.

Effect of endometrial scratching on unassisted conception for unexplained infertility: a randomized controlled trial

OBJECTIVE

To investigate whether endometrial scratching increases the chance of live birth in women with unexplained infertility attempting to conceive without assisted reproductive technology.

DESIGN

Randomized, placebo-controlled, participant-blind, multicenter international trial.

SETTING

Fertility clinics.

PATIENT(S)

Women with a diagnosis of unexplained infertility trying to conceive without assistance.

INTERVENTION(S)

Participants were randomly assigned to receive an endometrial biopsy or a placebo procedure (placement of a biopsy catheter in the posterior fornix, without inserting it into the external cervical os). Both groups performed regular unprotected intercourse with the intention of conceiving over three consecutive study cycles.

MAIN OUTCOME MEASURE(S)

The primary outcome was live birth.

RESULT(S)

A total of 220 women underwent randomization. The live birth rate was 9% (10 of 113 women) in the endometrial-scratch group and 7% (7 of 107 women) in the control group (adjusted OR, 1.39; 95% CI, 0.50-4.03). There were no differences between the groups in the secondary outcomes of clinical pregnancy, viable pregnancy, ongoing pregnancy, and miscarriage. Endometrial scratching was associated with a higher pain score on a 10-point scale (adjusted mean difference, 3.07; 95% CI, 2.53-3.60).

CONCLUSION(S)

This trial did not find evidence that endometrial scratching improves the live birth rate in women with unexplained infertility trying to conceive without assistance.

CLINICAL TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry ACTRN12614000656639.

A randomized trial of endometrial scratching in women with PCOS undergoing ovulation induction cycles

RESEARCH QUESTION

Does endometrial scratching improve the chance of a live birth in women with polycystic ovary syndrome (PCOS) undergoing ovulation induction and trying to conceive?

DESIGN

An international, multicentre, randomized, sham-controlled trial across six fertility clinics in three countries (New Zealand, UK and Brazil). Women with a diagnosis of PCOS who were planning to commence ovulation induction cycles (at least three cycles) in order to conceive were randomly assigned to receive the pipelle (scratch) procedure or a sham (placebo) procedure in the first cycle of ovulation induction. Women kept a diary of ovulation induction and sexual intercourse timing over three consecutive cycles and pregnancies were followed up to live birth. Primary outcome was live birth and secondary outcomes were clinical pregnancy, ongoing pregnancy, multiple pregnancy, adverse pregnancy outcomes, neonatal outcomes, bleeding following procedure and pain score following procedure.

RESULTS

A total of 117 women were randomized; 58 to the scratch group and 59 to the sham group. Live birth occurred in 11 (19%) women in the scratch group and 14 (24%) in the sham group (odds ratio 0.76, 95% confidence interval [CI] 0.30-1.92). Secondary outcomes were similar in each group. Significantly higher pain scores were reported in the scratch group (adjusted mean difference 3.2, 95% CI 2.5-3.9) when measured on a visual analogue scale.

CONCLUSION

No difference was detected in live birth rate for women with PCOS who received an endometrial scratch when trying to conceive using ovulation induction; however, uncertainty remains due to the small sample size in this study.

Meta-analysis of the embryo freezing transfer interval

BACKGROUND

The decision of whether frozen embryo transfer (FET) should be performed in the cycle immediately after OPU or at least one cycle later is controversial. FET could improve pregnancy rates in IVF; however, how much time is needed for the endometrium to return to optimal receptivity after ovarian stimulation is not known.

METHODS

Electronic search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials to identify studies providing data on the influence of the interval between embryo freezing (or OPU) and FET in FET cycles published between January 1, 2007, and February 1, 2020.

MAIN FINDINGS

Data analyzed indicated that in the immediate FET cycles, there was a trend to an increased biochemical pregnancy rate (RR = 1.08; CI = 1.00-1.18), whereas the clinical pregnancy rate was somewhat higher, but without reaching statistical significance (RR = 1.07; CI = 0.99-1.15). The live birth rate was similar in the two groups (RR = 1.05; CI = 0.95-1.15), as was the implantation rate (RR = 0.98; CI = 0.83-1.16). Stratifying by embryo stage or FET type (freeze-all or FET after failed fresh transfer) showed no differences.

CONCLUSION

Systematically delaying FET does not offer benefits to IVF outcomes. In addition, immediate transfer is associated with a nonsignificant trend to better clinical pregnancy rate and it also avoids the psychological effects of prolonging the stress on prospective parents.

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.

Spontaneous pregnancies and determinant factors in infertility: A cross-sectional study

Background

The phenomenon of infertility may be derived from different factors - either in males or females or both genders, including few unexplained factors. It is generally managed by medical and surgical treatments.

Objective

To find a relation of occurrence of spontaneous pregnancy (SP) with effective factors in infertility.

Materials and Methods

This cross-sectional study was conducted at two referral infertility centers (university and privacy center) in the southwest of Iran from March 2015 and March 2016 on 655 infertile couples, who were divided in two groups of with (n = 31) and without (n = 624) SP. The variables included female and male age, male smoking, male job, the place of living, the causes of infertility, the type and duration of infertility, and the subgroups of infertility causes.

Results

Infertility may be caused due to both male- and female- related factors (47.5%). While female-related infertility was found in 31.5%, male-related infertility in 14.5%, and infertility due to unexplained factors in 6.6% of our patients. The rate of SP was 4.7%, which had a significant relation with the duration of infertility (p = 0.01), with women's age (p = 0.048), unexplained infertility (p = 0.001), and husband's job (p = 0.004).

Conclusion

The occurrence of SP in infertile couples was related to age of the female partner, the duration of unexplained infertility, and the male partner's job.