The human factor: does the operator performing the embryo transfer significantly impact the cycle outcome?

The use of an embryo transfer simulator to compare transfer techniques and pregnancy outcomes among physicians

Objective

To evaluate the association between embryo transfer techniques and pregnancy outcomes.

Design

This is a prospective observational study with a retrospective cohort.

Setting

University Clinic.

Patients

Patients underwent embryo transfers between 2015 and 2020.

Intervention/Exposure

Fourteen physicians performed 25 mock embryo transfers on the embryo transfer simulator and completed a questionnaire assessing preferred embryo transfer techniques. Quantitative performance metrics on the embryo transfer simulator were measured. Individual physician embryo transfer success rates were retrospectively collected from all fresh and cryopreserved embryo transfers between January 1, 2015, and January 1, 2020. Associations between embryo transfer techniques (preferred technique and simulator performance metrics) and each physician's historical patient pregnancy outcomes were assessed.

Main Outcome Measures

Associations between embryo transfer techniques and live births were assessed.

Results

There were significant differences in embryo transfer techniques between physicians, including touches to the fundus, distance to the fundus, duration of embryo transfer, duration of the complete procedure, time spent navigating the cervical canal, velocity of embryo expulsion, time waited after embryo expulsion, and total score on the embryo transfer simulator. After controlling for confounders and multiple transfers per physician, the duration of embryo transfer was significantly associated with live birth, with longer durations associated with decreased live birth rates. Shorter placement distance to the fundus and higher velocity of embryo expulsion were both significantly associated with higher rates of ectopic pregnancy.

Conclusions

This study revealed significant differences in transfer techniques among physicians. The use of the embryo transfer simulator for physicians in practice can elucidate differences and create opportunities for data-driven improvement in embryo transfer success rates.

The impact of difficult embryo transfer on the success of IVF: a systematic review and meta-analysis

The procedure of embryo transfer (ET) must be as gentle as possible since any traumatism may cause uterine contractility that interferes with the implantation. However, this ideal conduct is not always possible, and additional measures may be necessary (difficult ET). Different studies have evaluated the impact of difficult ET on the clinical pregnancy rate (CPR), but results were not univocal. The present systematic review and meta-analysis was aimed to provide a precise estimate of the possible detrimental effects of difficult ET on CPR. The study protocol was registered online (PROSPERO number: CRD42023387197). An electronic database search was performed to identify articles published until September 2022. The primary outcome was CPR. Fifteen studies fulfilled the inclusion criteria. Difficult ET significantly reduced the CPR (OR 0.70; 95%CI: 0.64-0.76; p < 0.0001. All pre-planned subgroup analyses according to study design (retrospective vs prospective studies), historical period (studies published before and after 2010), type of catheter, frequency of difficult cases (> or < 19%) and pregnancy rate (> or < 38%) confirmed the significant association. Difficult ET is associated with a significant reduction of CPR. Further studies are warranted to understand how to prevent or manage this common clinical situation.

Steps forward in embryo transfer technique: a retrospective study comparing direct versus afterload catheters at different time frames

PURPOSE

To assess whether embryo transfer (ET) technique can influence the clinical pregnancy rate (CPR) and its correlation with the embryo transfer difficulty.

DESIGN

This single center retrospective cohort analysis of fresh and frozen single blastocyst transfers performed between January 2016 and December 2021 included fresh and frozen single blastocyst transfers performed during the study timeframe. Direct technique was the only one used from January 2016 to September 2017. From September 2017 to March 2019, the choice between the two techniques was given by randomization, due to a clinical trial recruitment. From April 2019, only the afterload technique was used. Preimplantation genetic testing cycles and gamete donation procedures and cycles performed with external gametes or embryos were excluded. CPR was the primary outcome, while difficult transfer rate the secondary one. Univariate and multivariate logistic regressions were performed.

RESULTS

During the period, 8,189 transfers were performed. CPR of the afterload group resulted significantly higher compared to the direct group (44.69% versus 41.65%, OR 1.13, 95% CI 1.02-1.25, p = 0.017) and the rate of difficult transfers two-thirds lower (9.06% versus 26.85%, OR 0.27, 95% CI 0.24-0.31, p < 0.001).

CONCLUSION

Our study demonstrated that CPR is significantly affected by the ET technique. In particular, with the afterload protocol, both CPR and easy transfer rates increased.

TRIAL REGISTRATION

http://clinicaltrials.gov registration number: NCT05364528, retrospectively registered on 3rd of May 2022.

Factors Affecting the Outcomes of First in vitro Fertilization and Embryo Transfer: A Retrospective Investigation

Background

The outcome of embryo transfer (ET) is multifactorial. A variety of patient-related, procedural-related, and operator-related factors are known to play a role. This study aims to evaluate the outcomes of ET and determine the factors that affect the outcome.

Methods

The study involved a retrospective design involving 300 first in vitro fertilization and embryo transfer (IVF-ET) cycles between 2011 and 2021. The outcome included 155 unsuccessful cycles and 145 successful IVF-ET leading to pregnancy. The outcomes were examined for different variables, including age, weight, height, body mass index, cause of infertility, number of embryos fertilized during the cycle, day of ET, whether the embryo was frozen, presence of blood or mucus during the procedure, the use of a stylet, tenaculum, uterine sound/dilator, and catheter type. Logistic regression was used to analyze factors affecting the outcomes of ET.

Results

The mean age was 27.84 ± 3.77 years. Patients who had blood during the procedure (32.9% vs 17.2%, p = 0.002), mucus (31% vs 20.7%, p = 0.049), or used the tenaculum (16.8% vs 6.9%, p = 0.012) were more likely to have unsuccessful IVF-ET. Logistic regression to adjust for related factors revealed that the presence of blood (AOR = 2.21, 95% CI 1.04 to 4.66, p = 0.038) during the ET had a higher likelihood of an unsuccessful outcome.

Conclusion

This study showed that the presence of blood during the ET cycle influenced clinical pregnancy. This highlights the importance of performing the procedure under atraumatic conditions.

Level of Evidence

Level III; retrospective comparative study.

Opening the black box: why do euploid blastocysts fail to implant? A systematic review and meta-analysis

BACKGROUND

A normal chromosomal constitution defined through PGT-A assessing all chromosomes on trophectoderm (TE) biopsies represents the strongest predictor of embryo implantation. Yet, its positive predictive value is not higher than 50-60%. This gap of knowledge on the causes of euploid blastocysts' reproductive failure is known as 'the black box of implantation'.

OBJECTIVE AND RATIONALE

Several embryonic, maternal, paternal, clinical, and IVF laboratory features were scrutinized for their putative association with reproductive success or implantation failure of euploid blastocysts.

SEARCH METHODS

A systematic bibliographical search was conducted without temporal limits up to August 2021. The keywords were '(blastocyst OR day5 embryo OR day6 embryo OR day7 embryo) AND (euploid OR chromosomally normal OR preimplantation genetic testing) AND (implantation OR implantation failure OR miscarriage OR abortion OR live birth OR biochemical pregnancy OR recurrent implantation failure)'. Overall, 1608 items were identified and screened. We included all prospective or retrospective clinical studies and randomized-controlled-trials (RCTs) that assessed any feature associated with live-birth rates (LBR) and/or miscarriage rates (MR) among non-mosaic euploid blastocyst transfer after TE biopsy and PGT-A. In total, 41 reviews and 372 papers were selected, clustered according to a common focus, and thoroughly reviewed. The PRISMA guideline was followed, the PICO model was adopted, and ROBINS-I and ROB 2.0 scoring were used to assess putative bias. Bias across studies regarding the LBR was also assessed using visual inspection of funnel plots and the trim and fill method. Categorical data were combined with a pooled-OR. The random-effect model was used to conduct the meta-analysis. Between-study heterogeneity was addressed using I2. Whenever not suitable for the meta-analysis, the included studies were simply described for their results. The study protocol was registered at http://www.crd.york.ac.uk/PROSPERO/ (registration number CRD42021275329).

OUTCOMES

We included 372 original papers (335 retrospective studies, 30 prospective studies and 7 RCTs) and 41 reviews. However, most of the studies were retrospective, or characterized by small sample sizes, thus prone to bias, which reduces the quality of the evidence to low or very low. Reduced inner cell mass (7 studies, OR: 0.37, 95% CI: 0.27-0.52, I2 = 53%), or TE quality (9 studies, OR: 0.53, 95% CI: 0.43-0.67, I2 = 70%), overall blastocyst quality worse than Gardner's BB-grade (8 studies, OR: 0.40, 95% CI: 0.24-0.67, I2 = 83%), developmental delay (18 studies, OR: 0.56, 95% CI: 0.49-0.63, I2 = 47%), and (by qualitative analysis) some morphodynamic abnormalities pinpointed through time-lapse microscopy (abnormal cleavage patterns, spontaneous blastocyst collapse, longer time of morula formation I, time of blastulation (tB), and duration of blastulation) were all associated with poorer reproductive outcomes. Slightly lower LBR, even in the context of PGT-A, was reported among women ≥38 years (7 studies, OR: 0.87, 95% CI: 0.75-1.00, I2 = 31%), while obesity was associated with both lower LBR (2 studies, OR: 0.66, 95% CI: 0.55-0.79, I2 = 0%) and higher MR (2 studies, OR: 1.8, 95% CI: 1.08-2.99, I2 = 52%). The experience of previous repeated implantation failures (RIF) was also associated with lower LBR (3 studies, OR: 0.72, 95% CI: 0.55-0.93, I2 = 0%). By qualitative analysis, among hormonal assessments, only abnormal progesterone levels prior to transfer were associated with LBR and MR after PGT-A. Among the clinical protocols used, vitrified-warmed embryo transfer was more effective than fresh transfer (2 studies, OR: 1.56, 95% CI: 1.05-2.33, I2 = 23%) after PGT-A. Lastly, multiple vitrification-warming cycles (2 studies, OR: 0.41, 95% CI: 0.22-0.77, I2 = 50%) or (by qualitative analysis) a high number of cells biopsied may slightly reduce the LBR, while simultaneous zona-pellucida opening and TE biopsy allowed better results than the Day 3 hatching-based protocol (3 studies, OR: 1.41, 95% CI: 1.18-1.69, I2 = 0%).

WIDER IMPLICATIONS

Embryo selection aims at shortening the time-to-pregnancy, while minimizing the reproductive risks. Knowing which features are associated with the reproductive competence of euploid blastocysts is therefore critical to define, implement, and validate safer and more efficient clinical workflows. Future research should be directed towards: (i) systematic investigations of the mechanisms involved in reproductive aging beyond de novo chromosomal abnormalities, and how lifestyle and nutrition may accelerate or exacerbate their consequences; (ii) improved evaluation of the uterine and blastocyst-endometrial dialogue, both of which represent black boxes themselves; (iii) standardization/automation of embryo assessment and IVF protocols; (iv) additional invasive or preferably non-invasive tools for embryo selection. Only by filling these gaps we may finally crack the riddle behind 'the black box of implantation'.

Embryo transfer learning using medical simulation tools: a comparison of two embryo transfer simulators

INTRODUCTION

Embryo transfer(ET) is one of the main procedures to become pregnant by assisted reproductive technology(ART). Simulation training is a way to improve the skills of clinicians. The objective of this study was to evaluate the interest of trainees in learning embryo transfer using simulators.

MATERIAL AND METHODS

An observational study was conducted at the University hospital-based research center. Trainees, comprising midwives and resident or graduated gynecologists, who attended the medical training for infertility and ART in June 2019, were included. They trained on two ET simulators (Simulator A and B) and complete an anonymously online questionnaire. A sub-group analysis focusing on graduated gynecologists not performing ET in current practice, was performed.

RESULTS

Thirty-two trainees were included. Trainees felt that ET simulators should be used in medical education to promote learning how to perform the ET procedure (n=26, 81.3% for Simulator A and n=21, 65.5% for Simulator B; p=0.31). The use of both simulators improved the level of self-confidence (81.3% and 75.0% respectively; p=0.55). Significant differences in the global and in the subgroup analysis (n=24) in favor of Simulator A were observed regarding learning the precision of the ET procedure (p<0.01), the pathway to introduce the catheter into the uterine cavity (p<0.05), and the guidance for proper placement of the catheter into the uterine cavity (p=0.03). In the subgroup analysis of graduated gynecologists not performing ET in current practice, Simulator A was found more realistic for the visualization of the introduction of the catheter into the uterine cavity (p=0.01) and more useful to learn about difficult cases (p=0.03).

CONCLUSION

Students expressed a high level of interest in ET simulators to improve their skills. Although the simulators displayed some differences regarding learning the precision of the ET procedure, both improved the level of self-confidence. This new learning method needs to be further developed in order to offer to trainees the most realistic simulators.

TRIAL REGISTRATION

This study was approved for publication by the Ethics Review Committee of the Cochin University Hospital (CLEP) (n° AAA-2020-08016) retrospectively registered.

Quality assurance (QA) for monitoring the performance of assisted reproductive technology (ART) staff using artificial intelligence (AI)

PURPOSE

Deep learning neural networks have been used to predict the developmental fate and implantation potential of embryos with high accuracy. Such networks have been used as an assistive quality assurance (QA) tool to identify perturbations in the embryo culture environment which may impact clinical outcomes. The present study aimed to evaluate the utility of an AI-QA tool to consistently monitor ART staff performance (MD and embryologist) in embryo transfer (ET), embryo vitrification (EV), embryo warming (EW), and trophectoderm biopsy (TBx).

METHODS

Pregnancy outcomes from groups of 20 consecutive elective single day 5 blastocyst transfers were evaluated for the following procedures: MD performed ET (N = 160 transfers), embryologist performed ET (N = 160 transfers), embryologist performed EV (N = 160 vitrification procedures), embryologist performed EW (N = 160 warming procedures), and embryologist performed TBx (N = 120 biopsies). AI-generated implantation probabilities for the same embryo cohorts were estimated, as were mean AI-predicted and actual implantation rates for each provider and compared using Wilcoxon singed-rank test.

RESULTS

Actual implantation rates following ET performed by one MD provider: "H" was significantly lower than AI-predicted (20% vs. 61%, p = 0.001). Similar results were observed for one embryologist, "H" (30% vs. 60%, p = 0.011). Embryos thawed by embryologist "H" had lower implantation rates compared to AI prediction (25% vs. 60%, p = 0.004). There were no significant differences between actual and AI-predicted implantation rates for EV, TBx, or for the rest of the clinical staff performing ET or EW.

CONCLUSIONS

AI-based QA tools could provide accurate, reproducible, and efficient staff performance monitoring in an ART practice.

Effect of retained embryos on pregnancy outcomes of in vitro fertilization: a matched retrospective cohort study

OBJECTIVES

To explore the incidence of retained embryos (REs) in embryo transfer (ET) cycles and its effects on pregnancy outcomes in women undergoing in vitro fertilization (IVF).

METHODS

This was a matched retrospective cohort study involving 29,160 ET cycles conducted from March 2016 to February 2021, in which ET cycles without RE were matched to the RE group at a 2:1 ratio. Clinical pregnancy, implantation, miscarriage, and live birth rates were compared between the with-RE and without-RE groups.

RESULTS

Our study showed that the overall incidence of REs was 0.33% (95/29,160). There was a statistically significant difference in RE rate among the operators (P < 0.001), suggesting that the embryo retention rate may be affected by the individual operator. A total of 95 repeated ET cycles due to RE were included in the study group, and 190 ET cycles without RE were matched to the study group (1:2). There were no significant differences between the RE and matched groups in terms of implantation rate (35.6 vs. 38.0%; P = 0.608), clinical pregnancy rate (47.4 vs. 54.7%; P = 0.240), biochemical pregnancy rate (5.3 vs. 4.7%; P = 0.846), miscarriage rate (11.1 vs. 9.6%; P = 0.781), ectopic pregnancy rate (2.2 vs. 1.9%; P = 1.000) or live birth rate (41.1 vs. 48.9%; P = 0.208).

CONCLUSIONS

The present findings demonstrated that immediate retransfer of REs did not significantly affect IVF outcomes, which may provide counselling information for patients when REs are identified and ET is reattempted. The incidence of REs was associated with the operator who expelled the embryos from the catheter. Attention to detail and frequent assessment of the operator's technique may facilitate avoidance of embryo retention.

Ectopic pregnancy risk factors in infertile patients: a 10-year single center experience

The present retrospective study included both intrauterine insemination and in vitro assisted reproductive technologies (ART) procedures performed from January 2009 to December 2018 at a tertiary-care Fertility Centre. The purpose was to assess the incidence of ectopic pregnancy (EP) in infertile population who undergoes ART and to identify any risk factor impacting the occurrence of EP after ART. Among 27,376 cycles, 7352 pregnancies were achieved, of which 132 were EPs, the 1.80% (95% CI 1.5-2.1) of all pregnancies. In fresh embryo transfer cycles, a history of prior pelvic adhesions showed the greatest impact on the incidence of EP (aOR 2.49 95% CI 1.53-4.07 p < 0.001). Other factors associated with EP incidence were also identified, such as female age, basal FSH, the transfer of blastocyst embryos and difficulties during the embryo transfer procedure. In frozen embryo transfer cycles, the only factor influencing the incidence of EP was anti Müllerian hormone (AMH) serum concentration (aOR 0.81 95% CI 0.65-1.00, p = 0.048). To conclude, the incidence of EP observed was comparable to that reported after natural conception. On the other hand, pre-existing risk factors, traditionally more common in infertile population, appeared to influence the incidence of EP and should thus be modified if possible.

Embryo transfer success: It is in our hands

Embryo transfer (ET) is considered as a critical step in the process of in vitro fertilization. Interestingly, studies have consistently shown significant outcome differences between physicians. Although the outcome of ET is not related to the physician's experience and specifically not different between fellows and attending physicians, certain techniques have been found to affect the success rate. This review summarizes the existing evidence regarding the impact of the individual physician performing ET and the techniques used.

Is There a Doctors' Effect on Patients' Physical Health, Beyond the Intervention and All Known Factors? A Systematic Review

Purpose

Despite billions of doctor visits worldwide each year, little is known on whether doctors themselves affect patients' physical health after accounting for intervention and confounders such as patients' and doctors' data, hospital effects, nor how strong that doctors' effect is. Knowledge of surgeons' and psychotherapists' effects exists, but not for 102 other medical specialties notwithstanding the importance of such knowledge.

Methods

Eligibility Criteria: Randomized controlled trials (RCTs), case-control, and cohort studies including medical doctors except surgeons for any intervention, reporting the proportion of variance in patients' outcomes owing to the doctors (random effects), or the fixed effects of grading doctors by outcomes, after multivariate adjustment. Exclusions: studies of <15 doctors or solely reporting doctors' effects for known variables.

Sources

Medline, Embase, PsycINFO, inception to June 2020. Manual search for papers referring/referred to by resulting studies.

Risk of Bias

Using Newcastle-Ottawa scale.

Results

Despite all medical interventions bar surgery being eligible, only thirty cohort papers were found, covering 36,239 doctors, with 10 specialties, 21 interventions, 60 outcomes (17 unique). Studies reported doctors' effects by grading doctors from best to worst, or by diversely calculating the doctor-attributed percentage of patients' outcome variation, ie the intra-class correlation coefficient (ICC). Sixteen studies presented fixed effects, 18 random effects, and 3 another approach. No RCTs found. Thirteen studies reported exceptionally good and/or poor performers with confidence intervals wholly outside the average performance. ICC range 0 to 33%, mean 3.9%. Highly diverse reporting, meta-analysis therefore not applicable.

Conclusion

Doctors, on their own, can affect patients' physical health for many interventions and outcomes. Effects range from negligible to substantial, even after accounting for all known variables. Many published cohorts may reveal valuable information by reanalyzing their data for doctors' effects. Positive and negative doctor outliers appear regularly. Therefore, it can matter which doctor is chosen.

The Doctors' Effect on Patients' Physical Health Outcomes Beyond the Intervention: A Methodological Review

Background

Previous research suggests that when a treatment is delivered, patients' outcomes may vary systematically by medical practitioner.

Objective

To conduct a methodological review of studies reporting on the effect of doctors on patients' physical health outcomes and to provide recommendations on how this effect could be measured and reported in a consistent and appropriate way.

Methods

The data source was 79 included studies and randomized controlled trials from a systematic review of doctors' effects on patients' physical health. We qualitatively assessed the studies and summarized how the doctors' effect was measured and reported.

Results

The doctors' effects on patients' physical health outcomes were reported as fixed effects, identifying high and low outliers, or random effects, which estimate the variation in patient health outcomes due to the doctor after accounting for all available variables via the intra-class correlation coefficient. Multivariable multilevel regression is commonly used to adjust for patient risk, doctor experience and other demographics, and also to account for the clustering effect of hospitals in estimating both fixed and random effects.

Conclusion

This methodological review identified inconsistencies in how the doctor's effect on patients' physical health outcomes is measured and reported. For grading doctors from worst to best performances and estimating random effects, specific recommendations are given along with the specific data points to report.

Is the lack of prior exposure to sperm antigens associated with worse neonatal and maternal outcomes? A 10 years single-center experience comparing ICSI-TESE pregnancies to ICSI pregnancies

BACKGROUND

Nowadays pathogenesis of preeclampsia is still unknown. Among the different etiological hypotheses, some authors proposed that it might be due to an abnormal immunologic response to foreign fetal antigen derived from the father's sperm. Indeed, the fetus is considered a semi allograft, being one half paternally derived in its antigenicity, and the first pathogenic insult of preeclampsia may be an abnormal maternal immune response towards this semi-allogenic implant. In the context of Artificial Reproductive Techniques, it has been shown that the use of donor and surgically retrieved spermatozoa (e.g. Testicular Sperm Extraction) increases the risk of preeclampsia, confirming the protective effect of sperm exposure on maternal complications.

OBJECTIVE

Determining whether the lack of exposure to sperm antigens is associated with worse maternal and neonatal outcomes in pregnancies obtained through intracytoplasmic sperm injection after testicular sperm extraction for obstructive azoospermia.

MATERIAL AND METHODS

This is a single-center case-control retrospective study, focusing on all first pregnancies obtained through intracytoplasmic sperm injection after testicular sperm extraction for obstructive azoospermia at Humanitas Fertility Center between January 1st, 2010 and December 31st, 2019. Controls included patients that achieved their first pregnancy with intracytoplasmic sperm injection and ejaculated sperm, for a diagnosis other than azoospermia, in the same time period. Cases were matched with controls in a 1:2 ratio, considering female age, female BMI and year of controlled ovarian stimulation. The primary outcome measure was the delivery rate, defined as the number of deliveries divided by the total number of clinical pregnancies. Secondary outcome measures focused on maternal and neonatal complications, such as miscarriage rate, rate of main obstetric complications, prematurity rate and rate of congenital malformations.

RESULTS

By analyzing overall 113 pregnancies among cases and 214 pregnancies among controls, this study showed that the delivery rate was higher in controls with respect to cases (92.06% vs 84.07%, p = 0.026); among deliveries, live births were respectively 98.95% and 100%, while only one stillbirth occurred in cases. The first trimester miscarriage rate was higher in the cases than controls (13.27% vs 6.07%, p = 0.027), while no difference was found among rate of second trimester miscarriages, therapeutic abortions and ectopic pregnancies. There was no difference regarding the rate of maternal complications, including gestational hypertension, preeclampsia, HELLP syndrome, gestational diabetes, placenta previa, placental abruption and premature rupture of the membranes. Considering neonatal complications, it was shown that twins belonging to controls had a higher prematurity rate with respect to cases (65.79% vs 50.00%) but without a statistical relevance. Lastly, the rate of congenital malformations did not differ among the two groups.

DISCUSSION

This study showed that, once couples diagnosed with obstructive azoospermia achieve a pregnancy, they have a much higher risk of miscarriage in the first trimester in respect to non-azoospermic patients. Moreover, controls had a higher delivery rate in respect to cases; however, when the fetal status at birth was compared, no difference was found between live births and stillbirths.

CONCLUSIONS

Differently from the findings in the literature, no association with preeclampsia was found. This might be related to a collider bias/left truncation bias: since azoospermic patients are at higher risk of early termination of pregnancy, it results that they do not have the possibility to develop preeclampsia and other adverse outcomes. This article is protected by copyright. All rights reserved.

Overlapping biosimilar and originator follitropin alfa preparations: How much closer can they get?

Unfounded skepticism relating to biosimilars, arising from the assertion that they are not molecularly identical to their original counterpart, fails to acknowledge that no biological medicine, including Gonal-f® (from Merck Serono) is identical to itself. Molecular differences between the biosimilar and the reference medicines are irrelevant and clinically undetectable as long as they are contained within the accepted variability in the original medicine. Accordingly, the minor differences in 'ongoing pregnancy rate' and 'live birth' rate reported in a recent meta-analysis of biosimilars and Gonal-f® are probably driven by product-unrelated factors, notwithstanding the fact that of the four products under analysis, only Ovaleap® (from Theramex) and Bemfola® (from Gedeon Richter Plc) can unambiguously be considered to be biosimilars. The EU biosimilars model has proven successful, but given the distrust in biosimilars that is built on a biased foundation, the full promise of rFSH alfa biosimilars for reproductive medicine patients is unlikely to be fulfilled.

Interventions to optimize embryo transfer in women undergoing assisted conception: a comprehensive systematic review and meta-analyses

BACKGROUND

Several interventions and techniques are suggested to improve the outcome of embryo transfer (ET) in assisted conception. However, there remains no consensus on the optimal practice, with high variations among fertility specialists.

OBJECTIVE AND RATIONALE

We conducted a comprehensive systematic review and meta-analyses of randomized controlled trials (RCTs) aiming to identify effective interventions that could be introduced around the time of ET to improve reproductive outcomes.

SEARCH METHODS

We searched the electronic databases (MEDLINE, EMBASE and Cochrane CENTRAL) from inception until March 2021 using a multi-stage search strategy of MeSH terms and keywords, and included all RCTs that evaluated an intervention in the 24-h period before/after ET in women undergoing IVF/ICSI. Our primary outcome was clinical pregnancy rate post-ET confirmed as viable pregnancy on ultrasound scan. We assessed the risk of bias in included trials and extracted data in duplicate. We pooled data using a random-effect meta-analysis and reported using risk ratio (RR) with 95% CI. We explored publication bias and effect modifiers using subgroup analyses.

OUTCOMES

Our search yielded 3685 citations of which we included 188 RCTs (38 interventions, 59 530 participants) with a median sample size of 200 (range 26-1761). The quality of included RCTs was moderate with most showing a low risk of bias for randomization (118/188, 62.8%) and attrition (105/188, 55.8%) but there was a significant risk of publication bias (Egger's test P = 0.001). Performing ET with ultrasound guidance versus clinical touch (n = 24, RR 1.265, 95% CI 1.151-1.391, I2 = 38.53%), hyaluronic acid versus routine care (n = 9, RR 1.457, 95% CI 1.197-1.261, I2 = 46.48%) and the use of a soft versus hard catheter (n = 27, RR 1.122, 95% CI 1.028-1.224, I2 = 57.66%) led to higher clinical pregnancy rates. Other pharmacological add-ons also showed a beneficial effect including granulocyte colony-stimulating factor (G-CSF: n = 4, RR 1.774, 95% CI 1.252-2.512, I2 = 0), Atosiban (n = 7, RR 1.493, 95% CI 1.184-1.882, I2 = 68.27%) and hCG (n = 17, RR 1.232, 95% CI 1.099-1.382, I2 = 57.76%). Bed rest following ET was associated with a reduction in clinical pregnancy (n = 6, RR 0.857, 95% CI 0.741-0.991, I2 = 0.01%). Other commonly used interventions, such as non-steroidal anti-inflammatory drugs, prophylactic antibiotics, acupuncture and cervical mucus removal, did not show a significant benefit on reproductive outcomes. Our effect estimates for other important outcomes, including miscarriage and live birth, were limited by the varied reporting across included RCTs.

WIDER IMPLICATIONS

Using ultrasound guidance, soft catheters and hyaluronic acid at the time of ET appears to increase clinical pregnancy rates. The use of Atosiban, G-CSF and hCG showed a trend towards increased clinical pregnancy rate, but larger trials are required before adopting these interventions in clinical practice. Bed rest post-ET was associated with a reduction in clinical pregnancy and should not be recommended.

Clinical aspects of oocyte retrieval and embryo transfer. Tips and tricks for the novice and experts

Oocyte retrieval (ovum pick-up) and embryo transfer (ET) are essential steps in IVF and ICSI and over the years, the two procedures were developed in order to improve the clinical outcome. Many suggestions were proposed and applied before, during and after oocyte retrieval such as timing of HCG trigger, pre-operative pelvic scan, vaginal cleansing, type of anesthesia, type and gauge of aspiration needles, aspiration pressure, follicle flushing, and the need for prophylactic antibiotics. Similarly, many steps were suggested and implemented before, during and after ET including patient's position, type of anesthesia/analgesia, dummy (mock) ET, ultrasound-guidance, HCG injection in the uterine cavity, use of relaxing agents, full bladder, removal of the cervical mucus, flushing the cervix with culture medium, type of ET catheter, embryo loading techniques, site of embryo deposition, the use of adherence compounds, as well as bed rest after ET. Complications were also reported with oocyte retrieval and ET. The aim of this review is to evaluate the current practice of these two procedures in the light of available evidence.

One step further: randomised single-centre trial comparing the direct and afterload techniques of embryo transfer

STUDY QUESTION

What are the differences in ease of use between two different embryo transfer (ET) techniques: the preload direct approach and the afterload approach.

SUMMARY ANSWER

The afterload technique seems to reduce the rate of difficult ETs.

WHAT IS KNOWN ALREADY

Numerous published trials now document that the ET procedure has an impact on pregnancy and delivery rates after IVF. Difficult transfers should be avoided, as they reduce implantation and pregnancy rates. Preload direct ETs with soft catheters under ultrasound guidance is currently considered the best procedure. However, when using soft catheters, it is not known which technique is preferable or which one should be implemented to reduce the operator factor.

STUDY DESIGN, SIZE, DURATION

This prospective randomised unblinded controlled clinical trial, included 352 ultrasound-guided ETs assigned to either direct ET or afterload ET, between September 2017 and March 2019. The sample size was calculated based on the historical rate of difficult ETs encountered between 2014 and 2015 with a direct ET procedure.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The inclusion criteria were women 18-38 years old, with BMI between 18 and 28, receiving a single-thawed blastocyst transfer. The exclusion criteria were use of testicular sperm and preimplantation genetic testing (PGT) cycles. The primary outcome was the rate of difficult or suboptimal transfers defined as: advancement of the outer sheath (specific for the direct transfer), multiple attempts, use of force, required manipulation, use of a stylet or tenaculum, dilatation, or use of a different catheter. The secondary outcome was clinical pregnancy rate.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 352 frozen ETs were randomised, with 176 patients in each group. The two arms were homogeneous for female and male age, female BMI, duration of infertility, secondary infertility, previous deliveries or miscarriages, myomas, previous surgery to the uterine cavity, cycle day at ovulation trigger, freeze all cycles, first transfers, indication for treatment, endometrial preparation protocol and duration, endometrial thickness, and blastocyst grade at vitrification. Across the entire population, 85 (24.1%) ETs were defined as difficult. The rate of difficult transfers was significantly higher in the direct ET group than in the afterload group: 68 (38.6%) versus 17 (9.7%), respectively (OR 0.17, 95% CI 0.09-0.30, P < 0.001). The mean percentage in the rate of difficult transfers per operator was 22.5% (SD ± 14.5%), of which 36.1% (SD ± 23.4%) were in the direct group compared with 8.6% (± 8.2%) in the afterload group (P < 0.001). The difficult transfer rate among operators varied from 0 to 43.8% (0-77.8% in the direct group and 0 to 25.0% in the afterload group). The clinical pregnancy rates (42.0% vs 48.3%, P = 0.239 in the direct and afterload groups, respectively) were not significantly different between the groups.

LIMITATIONS, REASONS FOR CAUTION

There were 18 experienced operators who participated in the trial. Conclusions about the pregnancy rate should not be generalised, since the sample analysis was not performed on this outcome and, although clinically relevant, the difference was not significantly different.

WIDER IMPLICATIONS OF THE FINDINGS

The rate of difficult transfers was significantly higher in the direct ET group compared with the afterload ET group, although a wide variation was observed among operators. Further studies regarding the association between transfer technique and ART outcomes are required.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was sought and there are no competing interests.

TRIAL REGISTRATION NUMBER

NCT03161119.

TRIAL REGISTRATION DATE

5 April 2017.

DATE OF FIRST PATIENT'S ENROLMENT

26 September 2017.

Embryos are exposed to a significant drop in temperature during the embryo transfer procedure: a pilot study

RESEARCH QUESTION

During the embryo transfer procedure, to what degree of temperature drop are embryos exposed to between loading the transfer catheter and placing it into the uterus?

DESIGN

Twenty-nine simulated embryo transfer procedures were carried out across five clinics. A thermocouple probe was used for standardized measurements inside the embryo transfer catheter to investigate the change in temperature that occurred in the time period between loading and placing the catheter in the uterus.

RESULTS

In all cases, the temperature at the loaded catheter tip fell rapidly to ambient temperature during transit from the embryo transfer workstation in the laboratory to the procedure room, even though embryo transfer procedures, ambient temperatures and embryo transfer catheter temperatures at loading varied between clinics.

CONCLUSIONS

Given the sensitivity of the pre-implantation embryo to its immediate environment, the rapid and profound drop in temperature observed at the catheter tip that houses the embryo during transit from laboratory to the uterus may affect embryo viability and health. This issue should be addressed to ensure that the tight temperature control aimed for by IVF laboratories continues throughout the embryo transfer procedure, and could improve clinical outcomes.

Predictive modeling in reproductive medicine: Where will the future of artificial intelligence research take us?

Artificial intelligence (AI) systems have been proposed for reproductive medicine since 1997. Although AI is the main driver of emergent technologies in reproduction, such as robotics, Big Data, and internet of things, it will continue to be the engine for technological innovation for the foreseeable future. What does the future of AI research look like?

Deep learning early warning system for embryo culture conditions and embryologist performance in the ART laboratory

Staff competency is a crucial component of the in vitro fertilization (IVF) laboratory quality management system because it impacts clinical outcomes and informs the key performance indicators (KPIs) used to continuously monitor and assess culture conditions. Contemporary quality control and assurance in the IVF lab can be automated (collect, store, retrieve, and analyze), to elevate quality control and assurance beyond the cursory monthly review. Here we demonstrate that statistical KPI monitoring systems for individual embryologist performance and culture conditions can be detected by artificial intelligence systems to provide systemic, early detection of adverse outcomes, and identify clinically relevant shifts in pregnancy rates, providing critical validation for two statistical process controls proposed in the Vienna Consensus Document; intracytoplasmic sperm injection (ICSI) fertilization rate and day 3 embryo quality.

Safety of Ovaleap® (Follitropin Alfa) in Infertile Women Undergoing Superovulation for Assisted Reproductive Technologies: A Multinational Comparative, Prospective Cohort Study

BACKGROUND

Ovaleap^® (follitropin alfa), a recombinant human follicle stimulating hormone, is a biosimilar medicinal product to Gonal-f^® and is used for ovarian stimulation. The main objective of this study was to assess the safety and effectiveness of Ovaleap^® compared to Gonal-f^® in one treatment cycle in routine clinical practice.

METHODS

Safety of Ovaleap^® Follitropin alfa in Infertile women undergoing superovulation for Assisted reproductive technologies (SOFIA) was a prospective cohort study conducted in six European countries. Eligible patients were infertile women undergoing superovulation for assisted reproductive technology, who were administered Ovaleap^® or Gonal-f^® for ovarian stimulation and were naïve to follicle stimulating hormone treatment. The recruitment ratio was 1:1. The primary endpoint was incidence proportion of ovarian hyperstimulation syndrome (OHSS) and the secondary endpoint was OHSS severity (Grades I, II, III). The effect of risk factors or potential confounders on the odds ratio for OHSS incidence as well as treatment effect on OHSS incidence was explored using univariate logistic regression. Pregnancy and live birth rates were also assessed.

RESULTS

A total of 408 women who were administered Ovaleap^® and 409 women who were administered Gonal-f^® were eligible for analysis. The incidence proportion of OHSS was 5.1% (95% CI: 3.4, 7.7) in the Ovaleap^® cohort and 3.2% (95% CI: 1.9, 5.4) in the Gonal-f^® cohort. This difference in OHSS incidence proportion between the two cohorts was not statistically significant neither before (p = 0.159) nor after univariate adjustment for each potential confounder (p > 0.05). The incidence proportion of OHSS severity grades was similar in the two treatment groups (3.4% versus 2.0% for Grade I, 1.2% versus 1.0% for Grade II, and 0.5% versus 0.2% for Grade III, in the Ovaleap^® and Gonal-f^® cohorts, respectively), without a significant statistical difference (p = 0.865, for each grade). Among patients who had embryo transfer, clinical pregnancy rates were 33% and 31% and live birth rates were 27% and 26%, in the two cohorts, respectively.

CONCLUSIONS

Findings from the SOFIA study indicate that the incidence proportions of OHSS and OHSS severity, as well as pregnancy and live birth rates, are similar between Ovaleap^® and Gonal-f^® treatments and corroborate the safety and effectiveness of Ovaleap^® as a biosimilar to Gonal-f^®.