Recurrent implantation failure in IVF: features of cycles that eventually ended in conception

Predictive models of recurrent implantation failure in patients receiving ART treatment based on clinical features and routine laboratory data

STUDY QUESTION

The objective was to construct a model for predicting the probability of recurrent implantation failure (RIF) after assisted reproductive technology (ART) treatment based on the clinical characteristics and routine laboratory test data of infertile patients. A model was developed to predict RIF. The model showed high calibration in external validation, helped to identify risk factors for RIF, and improved the efficacy of ART therapy.

WHAT IS KNOWN ALREADY

Research on the influencing factors of RIF has focused mainly on embryonic factors, endometrial receptivity, and immune factors. However, there are many kinds of examinations regarding these aspects, and comprehensive screening is difficult because of the limited time and economic conditions. Therefore, we should try our best to analyse the results of routine infertility screenings to make general predictions regarding the occurrence of RIF.

STUDY DESIGN, SIZE, DURATION

A retrospective study was conducted with 5212 patients at the Reproductive Center of the First Affiliated Hospital of USTC from January 2018 to June 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study included 462 patients in the RIF group and 4750 patients in the control group. The patients' basic characteristics, clinical treatment data, and laboratory test indices were compared. Logistic regression was used to analyse RIF-related risk factors, and the prediction model was evaluated by receiver operating characteristic (ROC) curves and the corresponding areas under the curve (AUCs). Further analysis of the influencing factors of live births in the first cycle of subsequent assisted reproduction treatment in RIF patients was performed, including the live birth subgroup (n = 116) and the no live birth subgroup (n = 200).

MAIN RESULTS AND THE ROLE OF CHANCE

(1) An increased duration of infertility (1.978; 95% CI, 1.264-3.097), uterine cavity abnormalities (2.267; 95% CI, 1.185-4.336), low AMH levels (0.504; 95% CI, 0.275-0.922), insulin resistance (3.548; 95% CI, 1.931-6.519), antinuclear antibody (ANA)-positive status (3.249; 95% CI, 1.20-8.797) and anti-β2-glycoprotein I antibody (A-β2-GPI Ab)-positive status (5.515; 95% CI, 1.481-20.536) were associated with an increased risk of RIF. The area under the curve of the logistic regression model was 0.900 (95% CI, 0.870-0.929) for the training cohort and 0.895 (95% CI, 0.865-0.925) for the testing cohort. (2) Advanced age (1.069; 95% CI, 1.015-1.126) was a risk factor associated with no live births after the first cycle of subsequent assisted reproduction treatment in patients with RIF. Blastocyst transfer (0.365; 95% CI = 0.181-0.736) increased the probability of live birth in subsequent cycles in patients with RIF. The area under the curve of the logistic regression model was 0.673 (95% CI, 0.597-0.748).

LIMITATIONS, REASONS FOR CAUTION

This was a single-centre regression study, for which the results need to be evaluated and verified by prospective large-scale randomized controlled studies. The small sample size for the analysis of factors influencing pregnancy outcomes in subsequent assisted reproduction cycles for RIF patients resulted in the inclusion of fewer covariates, and future studies with larger samples and the inclusion of more factors are needed for assessment and validation.

WIDER IMPLICATIONS OF THE FINDINGS

Prediction of embryo implantation prior to transfer will facilitate the clinical management of patients and disease prediction and further improve ART treatment outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the General Project of the National Natural Science Foundation of China (Nos. 82,201,792, 82,301,871, 81,971,446, and 82,374,212) and the Natural Science Foundation of Anhui Province (No. 2208085MH206). There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

This study was registered with the Chinese Clinical Trial Register (Clinical Trial Number: ChiCTR1800018298 ).

Management of recurrent implantation failure: British Fertility Society policy and practice guideline

Recurrent implantation failure (RIF) is defined as the absence of a positive pregnancy test after three consecutive transfers of good quality embryos. There remains significant variation in clinical practice in the management of RIF. This British Fertility Society (BFS) Policy and Practice guideline analyses the evidence for investigations and therapies that are employed in RIF and provides recommendations for clinical practice and for further research. Evidence for investigations of sperm and egg quality, uterine and adnexal factors, immunological factors and thrombophilia, endocrine conditions and genetic factors and for associated therapies have been evaluated. This guideline has been devised to assist reproductive medicine specialists and patients in making shared decisions concerning management of RIF. Finally, suggestions for research towards improving understanding and management of RIF have also been provided.

Analysis of blocking antibodies and lymphocyte subsets in patients with recurrent reproductive failure

This study aimed to explore the relationship between recurrent reproductive failure (RRF) and blocking antibody (BA) and lymphocytes, to explore the difference of immune status between recurrent spontaneous abortion (RSA) and recurrent implantation failure (RIF) patients. We undertook a retrospective analysis of BA and lymphocyte subsets detected by flow cytometry in 720 RRF patients (411 RSA and 309 RIF patients) who were treated at Shanxi Maternal and Child Health Hospital from April 2015 to October 2019. The BA negative rate of RRF patients was 81.80%, which was significantly higher than that of normal women (23.46%) (p < 0.05). There was no significant difference in BA negative rates between RSA and RIF patients. Compared with the normal value, the percentage of CD3⁺ T lymphocytes and CD3⁺CD4⁺ T lymphocytes in RRF patients were 71.1% (65.9-76.0) and 36.8% (32.5-41.9) respectively, which were significantly lower than the normal value (p < 0.05). The percentage of B cells in RSA patients [11.0 (8.8-13.9)] was significantly lower than that in RIF patients [11.9 (9.4-14.8)]. The occurrence of RRF is related to the lack of BA and the change of lymphoid subsets. There are some differences in immune status between RSA and RIF patients.

Recurrent implantation failure: which patients benefit from endometrial scratching prior to IVF?

PURPOSE

Endometrial scratching (ES) using a biopsy catheter prior to the IVF cycle in the repeated implantation failure (RIF) population has been suggested, but no convincing evidence of its benefit has been presented until now.

METHODS

A retrospective mono-center study among 300 consecutive IVF-RIF cycles following evaluation of the ovarian reserve, hysterosalpingography or hysteroscopy, pelvic ultrasound, thrombophilia evaluation, karyotyping and assessment of male sperm parametrs. The findings within normal limits. All the patients offered ES, 78 consented and underwent ES prior to their next IVF cycle.

RESULTS

A comparison of treatment outcomes between the post-ES cycles (n = 78) and the non-ES cycles (222) demonstrated the following: 34 (43.5%) versus 14 (6.3%) conceptions, respectively (p = 0.001) and 30 (38.4%) versus 2 (0.9%) clinical pregnancies, respectively (p < 0.001%), emphasizing an extremely high biochemical pregnancy rate among the non-ES cycles. Implantation rate was 19.7% versus 0.4%, respectively (p < 0.001) and live birth rate was 33.33% (26 newborns) versus 0.45% (1 newborn), respectively (p < 0.001). Since there were more embryos available for transfer and more top-quality embryos in the post-ES-IVF conception cycles, the role of ES became questionable. A multivariate analysis that included ES and the percentage of top-quality embryos demonstrated that ES was an independent factor highly correlated with conception in this particular RIF population.

CONCLUSIONS

ES proved to be an efficient tool in a particular subgroup of RIF patients with fertility investigation results within normal limits, an optimal ovarian response to gonadotropins, and a high percentage of top-quality embryos. Nevertheless, the results should not be overestimated, since the study has limitations related to its retrospective model.

Reduced Protein C Global Assay Levels in Infertile Women with in vitro Fertilization Failure: A Pilot Study

Protein C global is a global dotting assay that evaluates abnormalities in the protein C anticoagulant pathway. A few studies have examined this assay in relation to assisted reproductive technology (ART), but its role in infertile women with in vitro fertilization (IVF) failure remains unclear. In this study, we assessed protein C in infertile women with a history of IVF failure who were undergoing ART. We examined 45 healthy fertile women who conceived naturally, and 45 infertile women with 2 or more implantation failures undergoing ART. Both protein C and activated protein C resistance (APC-R) were evaluated. The results showed that mean protein C expressed as a normalized ratio (PCAT-NR) was significantly lower in the study group compared to the control group (0.76 ± 0.15 vs. 0.91 ± 0.14, respectively; p = 0.0001). Follow-up on ART outcomes showed that women who failed ART had significantly lower PCAT-NR compared to successful cases. PCAT-NR did not correlate with APC-R levels in the study (r = 0.125, p < 0.5) or failed ART subgroups. Using logistic regression analysis, patients with lower PCAT-NR levels showed an elevated risk of implantation failure (p = 0.04, OR 0.50, 95% CI 0.26-0.84). In conclusion, protein C global assay may play a role in the etiology of IVF failure, which might be independent of APC-R. Larger studies are encouraged to validate these findings and explore the underlying pathophysiological mechanisms.

A meta-analysis of atosiban supplementation among patients undergoing assisted reproduction

OBJECTIVES

Evidence for the efficacy of atosiban in improving pregnancy outcomes among patients undergoing assisted reproductive technology (ART) remains inconsistent.

METHODS

The PubMed, EMBASE, and CNKI databases were searched using keywords such as 'atosiban', 'infertility', and 'ART'. Studies that explored the efficacy of atosiban in the field of ART for patients with embryo transfer (ET) were included if they evaluated pregnancy outcomes. Combing using subgroups and sensitivity analysis were conducted, and risk ratios (RRs), and 95% confidence intervals (CIs) were calculated.

RESULTS

Six studies were included. Atosiban treatment could improve pregnancy outcomes for all patients undergoing ET, especially for the subgroups of patients with repeated implantation failure (RIF) (implantation rate: RR = 1.806, 95% CI = 1.473-2.215; clinical pregnancy rate: RR = 1.725, 95% CI = 1.394-2.135; live birth rate: RR = 2.141, 95% CI = 1.494-3.068), as shown by the comparison with placebo or no-treatment groups. However, no statistical significance was detected in subgroups of patients undergoing their first or second ET cycle. In addition, no significant differences were observed in positive pregnancy tests, miscarriage rates, multiple pregnancy rates, or ectopic pregnancy rates.

CONCLUSIONS

Supplementation with atosiban has a positive effect on ART and embryo transfer procedure, especially for women undergoing their third or more ET cycle.