Pregnancy rates after embryo transfer depend on the provider at embryo transfer

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.

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.

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.

Simulation-based training for embryo transfer for clinicians with differing levels of expertise: an application of the American Society for Reproductive Medicine Embryo Transfer Simulator

Objective

To compare the learning curve of clinicians with different levels of embryo transfer (ET) experience using the American Society for Reproductive Medicine (ASRM) Embryo Transfer Simulator.

Design

Prospective cohort study.

Setting

Single large university-affiliated in vitro fertilization center.

Patients

Participants with 3 levels of expertise with ET were recruited: "group 1" (Reproductive Endocrinology and Infertility attendings), "group 2" (Reproductive Endocrinology and Infertility nurses, advance practice providers, or medical assistants), and "group 3" (Obstetrics and Gynecology resident physicians).

Interventions

All participants completed ET simulation training using uterine cases A, B, and C (easiest to most difficult) of the ASRM ET Simulator. Participants completed each case 5 times for a total of 15 repetitions.

Main Outcome Measures

The primary outcome was ET simulation scores analyzed at each attempt for each uterine case, with a maximum score of 155. Secondary outcomes included self-assessed comfort levels before and after the completion of the simulation and total duration of ET. Comfort was assessed using a 5-point Likert scale.

Results

Twenty-seven participants with 3 different levels of expertise with ET were recruited from December 2020 to February 2021. For cases A and B, median total scores were not significantly different between groups 1 and 3 at first or last attempts. Group 2 did not perform as well as group 3 at the beginning of case A or group 1 at the end of case B. All groups demonstrated a decrease in total time from the first attempt to the last attempt for both cases. For case C, the "difficult" uterus, groups 2 and 3 exhibited the greatest improvement in total median score: from 0 to 75 from the first to last attempt. Group 1 scored equally well from first through last attempts. Although no one from group 2 or 3 achieved a passing score with the first attempt (80% of the max score), approximately 30% had passing scores at the last attempt. Groups 1 and 3 showed a significant decrease in total time across attempts for case C. Following simulation, 100% of groups 2 and 3 reported perceived improvement in their skills. Group 3 showed significant improvement in comfort scores with Likert scores of 1.71 ± 0.76 and 1.0 ± 0.0 for the "Easy" and "Difficult" cases, respectively, before simulation and 4.57 ± 0.53 and 2.4 ± 1.1 after simulation.

Conclusions

The ASRM ET Simulator was effective in improving both technical skill and comfort level, particularly for those with little to no ET experience and was most marked when training on a difficult clinical case.

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.

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.

Impact of governmental support to the IVF clinical pregnancy rates: differences between public and private clinical settings in Kazakhstan-a prospective cohort study

OBJECTIVES

Infertility rates have been increasing in low-income and middle-income countries, including Kazakhstan. The need for accessible and affordable assisted reproductive technologies has become essential for many subfertile women. We aimed to explore whether the public funding and clinical settings are independently associated with in vitro fertilisation (IVF) clinical pregnancy and to determine whether the relationship between IVF clinical pregnancy and clinical settings is modified by payment type.

DESIGN

A prospective cohort study.

SETTING

Three private and two public IVF clinics located in major cities.

PARTICIPANTS

Women aged ≥18 seeking first or repeated IVF treatment and agreed to complete a survey were included in the study. Demographical and previous medical history data were collected from a survey, while clinical data from medical records. The total response rate was 14%.

PRIMARY AND SECONDARY OUTCOME MEASURES

Clinical pregnancy was defined as a live intrauterine pregnancy identified by ultrasound scan at 8 gestational weeks. The outcome data were missing for 22% of women.

RESULTS

Out of 446 women in the study, 68.2% attended private clinics. Two-thirds of women attending public clinics and 13% of women attending private clinics were publicly funded. Private clinics retrieved, on average, a higher number of oocytes (11.5±8.4 vs 8.1±7.2, p<0.001) and transferred more embryos (2.2±2.5 vs 1.4±1.1, p<0.001) and had a statistically significantly higher pregnancy rate compared with public clinics (79.0% vs 29.7%, p<0.001). Publicly funded women had on average a higher number of oocytes retrieved and a statistically significantly higher probability of clinical pregnancy (RR=1.23, 95% CI 1.02 to 1.47) than self-paid women, after adjusting for covariates. There was no statistically significant interaction between clinical setting and payment type.

CONCLUSIONS

Private clinics and public funding were independently associated with higher IVF clinical pregnancy rates. There is also a need to further investigate whether the increase in public funding will influence clinical pregnancy rates.

Is There Any Effect of the Physician Performing Embryo Transfer in IVF-ICSI Treatment: A Prospective Cohort Study

OBJECTIVE

 To evaluate whether there is an effect of the physician who transfers the embryos on pregnancy rates in in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) treatment.

METHODS

 A total of 757 participants were analyzed between 2012 and 2017. Participants were classified according to 3 physicians who transferred the embryos: ([group 1 = 164 patients]; [group 2 = 233 patients]; [group 3 = 360 patients]). Baseline parameters and IVF-ICSI outcomes were compared between the groups.

RESULTS

 No differences were determined between the groups regarding the baseline parameters (age, age subgroups [20-29, 30-39, and ≥ 40 years old)], body mass index (BMI), smoking status, infertility period, cause of infertility, baseline follicle stimulating hormone, luteinizing hormone, estradiol (E₂), thyroid stimulating hormone, prolactin levels, antral follicle count, duration of stimulation, stimulation protocol, gonadotropin dose required, maximum E₂ levels, progesterone levels, endometrial thickness on human chorionic gonadotropin (hCG) administration and transfer days (p > 0.05). The numbers of oocytes retrieved, metaphase II (MII), 2 pronucleus (2PN), , transferred embryo, fertilization rate, day of embryo transfer, the catheter effect and embryo transfer technique, and clinical pregnancy rates (CPRs) were also comparable between the groups (p > 0.05).

CONCLUSION

 Our data suggests that the physician who transfers the embryos has no impact on CPRs in patients who have undergone IVF-ICSI, but further studies with more participants are required to elucidate this situation.

Outcomes of embryo transfers performed by Reproductive Endocrinology and Infertility fellows vs. faculty: an 11-year retrospective review

OBJECTIVE

To compare the clinical pregnancy rate (CPR) and live birth rate (LBR) of embryo transfer episodes (ETEs) performed by Reproductive Endocrinology and Infertility fellows vs. those of ETEs performed by faculty physicians.

DESIGN

Retrospective cohort analysis.

SETTING

Academic reproductive endocrinology and infertility practice.

PATIENT(S)

In total, 3,073 ETEs for 1,488 unique patients were performed by fellows or faculty physicians between January 2009 and January 2020.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate and LBR.

RESULT(S)

Fifteen fellows performed 1,225 (39.9%) of 3,073 ETEs after completing 30 mock transfers. On comparing outcomes among fellowship years (FY1, FY2, and FY3), CPR (44.1% vs. 43.2% vs. 45.7%, respectively, P = .83) and LBR (39.1% vs. 38.1% vs. 38.4%, respectively, P = .97) were not significantly different. Fellowship year 1 fellows' initial 30 ETEs vs. all the remaining FY1 ETEs had a significantly higher CPR (48.1% vs. 40.5%, respectively, P = .030) and LBR (45.4% vs. 34.3%, respectively, P = .001). There were no significant differences between faculty versus fellow ETEs in terms of CPR (43.0% vs. 45.0%, respectively, P = .30) or LBR (37.3% vs. 39.8%, respectively, P = .16), even after adjusting for patient age, body mass index, primary infertility diagnosis, autologous vs. donor oocyte, fresh vs. frozen embryo, number of embryos transferred, type of transfer catheter, and year of transfer (P = .32 for CPR, P = .22 for LBR).

CONCLUSION(S)

Appropriately trained FY1 fellows had success rates maintained throughout all FYs. There were no significant differences in clinical outcomes between fellow- and faculty-performed transfers. These data demonstrated that allowing fellows to perform live embryo transfers is not detrimental to clinical outcomes.

National Survey Highlights the Urgent Need for Standardisation of Embryo Transfer Techniques in the UK

Embryo transfer (ET) is one of the vital steps in the in vitro fertilisation (IVF) process, yet there is wide variation in ET technique throughout the UK, without a nationally approved standardised approach. The aim of this study was to gain contemporaneous information regarding the current clinical ET practice in the UK.

METHOD

A 38-question electronic survey was distributed to the 79 UK Human Fertilisation and Embryology Authority (HFEA) registered clinics performing ETs.

RESULTS

In total, 59% (47/79) of units responded, 83% (39/47) performing ultrasound-guided transfers, with 42% (20/47) of units using a tenaculum; 22% (10/45) would proceed with transfer regardless of fluid in the endometrial cavity. In 91% (43/47) of units, embryos were deposited in the upper/middle portion of the uterine cavity, but interpretation of this area ranged from 0.5 to >2 cm from the fundus, with 68% (32/47) allowing patients to mobilise immediately after transfer. In 60% (27/45) of clinics, success rates were based on clinical pregnancy rates (CPR).

CONCLUSION

Within the UK there is a wide range of variability in ET techniques, with >70% of discordance in survey-responses between clinics. Whilst there are areas of good practice, some disadvantageous techniques continue to persist. This survey emphasises the importance of developing a standardised, evidence-based approach to improve ET success rates.

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

STUDY QUESTION

Is Ongoing Pregnancy Rate (OPR) operator-dependent, and can experience improve embryo transfer efficiency?

SUMMARY ANSWER

OPR is influenced by the operators who perform the embryo transfer (ET), and experience does not assure proficiency for everyone.

WHAT IS KNOWN ALREADY

ET remains the critical step in assisted reproduction. Although many other factors such as embryo quality and uterine receptivity impact embryo implantation, the proper ET technique is clearly an operator-dependent variable and as such it should be objectively standardized.

STUDY DESIGN, SIZE, DURATION

Retrospective comparative analysis including all fresh ETs performed between January 1996 and December 2016 at the Humanitas Fertility Center after IVF—ICSI cycles.

PARTICIPANTS/MATERIALS, SETTING, METHODS

IVF/ICSI fresh ETs performed by 32 operators, 19 824 cycles in all, were analyzed. All transfers consisting of freehand insertion of a preloaded soft catheter into the uterine cavity under transabdominal ultrasound guidance were considered. Two different statistical analyses were performed. First, a logistic regression model with a random intercept for the operator was used to estimate the heterogeneity of the rate of success among operators, accounting for woman age, FSH, number of oocytes retrieved, fertilization rate, year of the procedure, number and stage of transferred embryos and operator’s experience. Second, the relationship between experience and pregnancy rate was estimated separately for each operator by logistic regression, and operator-specific results were combined and compared in a random-effects meta-analysis. In both analyses, the operator’s experience at time t was measured in terms of number of embryo transfers performed before t.

MAIN RESULTS AND THE ROLE OF CHANCE

The heterogeneity among operators was highly significant (P value <0.001) and explained 44.5% of the total variability. The odds ratio of success of the worst operator in respect to the mean was equal to 0.84. For the best operator, the odds ratio of success was equal to 1.13 in respect to the mean. Based on the meta-analysis of the relationship between operator’s experience and success rate, it resulted that, on average, the operators’ performance did not improve with additional transfers.

LIMITATIONS, REASONS FOR CAUTION

At our center, operators become independent for ET’s after performing between 30 and 50 transfers under supervision. It is also possible that other relevant factors, such as embryologists on duty for the ET, have not been included in the present analysis and this may represent a potential bias. Among these, it should be mentioned that the embryologists on duty for the ET were not taken into consideration.

WIDER IMPLICATIONS OF THE FINDINGS

Continued performance analysis and the use of a digital simulator could help operators to test their expertise over time and either correct poor performance or avoid doing transfers.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

NCT03561129.

Simulation training for embryo transfer: findings from the American Society for Reproductive Medicine Embryo Transfer Certificate Course

OBJECTIVE

To assess the value of the American Society for Reproductive Medicine Embryo Transfer Certificate Course in confidence and skill building for performing a live embryo transfer (ET).

DESIGN

Prospective cohort study.

SETTING

Two-day simulation workshops of reproductive endocrine and infertility (REI) fellows from American Board of Obstetrics and Gynecology-approved training programs, using four different uterine models (A-D).

PATIENT(S)

None.

INTERVENTION(S)

Didactic and hands-on simulation training program.

MAIN OUTCOME MEASURE(S)

Primary outcomes included ET simulation scores of all exercises analyzed at various points of the training and self-assessed confidence before and after the completion of the Embryo Transfer Certificate Course based on a 6-point Likert scale and association of both with extent of prior live ET experience and year of fellowship.

RESULT(S)

Data were collected for 78 REI fellows who completed the Embryo Transfer Certificate Course and demonstrated significant improvements in both skill and confidence. The data for a subset of 58 fellows who performed five direct transfers on both Embryo Transfer Certificate Course uterine models A and B demonstrated significant overall improvement in ET simulation scores between the first and fifth direct transfers. A separate data subset of 57 fellows who performed five afterload transfers for each exercise on all four uterine models demonstrated differences in difficulty among them. Embryo transfer simulation using the uterine A model was consistently the easiest. The ET simulation scores for fellows using the uterine B and C models showed a progressive and significant increase across the five afterload ETs. When using the uterine D model, ET simulation scores increased significantly between the first and second transfers but remained at the same level for the remaining three transfers. Except for uterus A, a significant increase in ET simulation scores between the first and last transfers was observed for fellows overall in all afterload transfers and for those fellows with <50 prior live transfers. Data for all 78 fellows demonstrate a significant gain of self-confidence for all parameters, with the highest overall increase (78%) observed for first-year fellows as well as for fellows of any year with no prior live transfer experience (109%). Fellows with the largest number of prior live ET experience started with higher confidence, which also increased significantly, although they had a lower gain in confidence compared with fellows with less experience.

CONCLUSION(S)

The American Society for Reproductive Medicine Embryo Transfer Certificate Course data analysis demonstrates the effectiveness of simulator-based ET training for REI fellows across the 3 years of training, regardless of prior experience with live ET.

Evaluation of fertilization, usable blastocyst development and sustained implantation rates according to intracytoplasmic sperm injection operator experience

RESEARCH QUESTION

Is intracytoplasmic sperm injection (ICSI) operator experience associated with fertilization, usable blastocyst development and sustained implantation rates (SIR) when at least two embryologists carry out ICSI for a single cohort of oocytes?

DESIGN

A retrospective cohort study of all IVF/ICSI cycles at a single large infertility centre between 2008 and 2018. Cycles were included if a cohort of oocytes was split between two embryologists for ICSI. The embryologist's experience of ICSI was used to evaluate laboratory and clinical outcomes overall and by pairs of inseminating embryologists. Logistic regression, analysis of variance and Kruskal-Wallis testing were used where appropriate.

RESULTS

Analysis of 14,362 ICSI procedures showed an association between least ICSI experience and lower mean fertilization rates (P < 0.0001), higher odds of failed fertilization (adjusted OR 4.3; P < 0.0001) and lower number of fertilization 'wins' per cohort (P < 0.0001). Usable blastocyst development rates (number of usable blastocysts/number of two pronuclear zygotes) were not associated with ICSI embryologist experience (P = 0.44), but the odds of obtaining no usable blastocysts were higher (adjusted OR 1.4; P < 0.0001) and the proportion of usable blastocyst 'wins' was lower (P = 0.0001) when embryologists with the least experience carried out ICSI. Increased ICSI experience was associated with higher mean SIR (P < 0.0001). Laboratory and clinical outcomes were similar among embryologists once 1000 ICSI cycles and above were carried out.

CONCLUSIONS

Increased ICSI operator experience is associated with higher fertilization rates, SIR and a lower likelihood of failed fertilization and usable blastocyst development. Splitting a single oocyte cohort between more than one embryologist for ICSI is a quality-control measure that can be implemented.

Is the clinician an independent variable in embryo transfer outcomes under standardized direct and indirect supervision? A 5-year observational cohort study

Objective: To compare the cumulative pregnancy rate (CPR) for experienced clinicians and trainees naive to the skill of embryo transfer (ET) during an assisted reproductive treatment (ART) cycle. To establish the minimum number of procedures required to achieve consistent outcomes. Method: A non-interventional retrospective observational cohort study looking at all consecutive ETs undertaken over a 5-year study period. The CPR was determined by a self-reported urinary home pregnancy test undertaken 16 days after oocyte retrieval. Results: The CPR did not differ between an experienced clinician (39%) and trainee (45%) for the first 50 (p=0.41) and last 50 (40.7% versus 42.7%) (p=0.81) ET procedures. The CPR for the individuals remained consistent with their peaks and troughs mirroring the overall success rate of the unit. This pattern continued when the data was further stratified for co-variables (age [≤37 years of age], catheter type [soft] and embryo quality [expanded blastocyst of grade ≥2]): CPRs for experienced clinicians was 65.7% (first 50 transfers) and 40.9% (last 50 transfers); CPR for trainees was 66.7% (first 50 transfers) and 53.6% (last 50 transfers); p=0.95 and p=0.37, respectively. The trainees, however, were more likely to use a stylet catheter with a 2-step transfer technique, with a cost over clinical implication. Furthermore, patients expressed a preference for an experienced clinician to perform their procedure, despite being informed that the grade of the clinician had no impact on the cycle outcome after an analysis of the unit's data. Conclusion: The clinician's grade and duration of service have not been shown to significantly impact the outcome of the ART cycle. The findings, however, should be interpreted with caution, as they reflect the culture of training in the unit, where there is a strong emphasis on adequate direct and indirect supervision. Furthermore, the relationship between the volume of work and outcomes is established in postgraduate medical education, with the exact number required to achieve clinical competence being dependent on the procedure and intensity of the workload.

Low versus high volume of culture medium during embryo transfer: a randomized clinical trial

PURPOSE

The aim of this prospective randomized control trial was to evaluate if the use of two different volumes (20-25 vs 40-45 μl) of media used for embryo transfer affects the clinical outcomes in fresh in vitro fertilization (IVF) cycles.

METHODS

In total, 236 patients were randomized in two groups, i.e., "low volume" group (n = 118) transferring the embryos with 20-25 μl of medium and "high volume" group (n = 118) transferring the embryos with 40-45 μl of medium. The clinical pregnancy, implantation, and ongoing pregnancy rates were compared between the two groups.

RESULTS

No statistically significant differences were observed in clinical pregnancy (46.8 vs 54.3%, p = 0.27), implantation (23.7 vs 27.8%, p = 0.30), and ongoing pregnancy (33.3 vs 40.0%, p = 0.31) rates between low and high volume group, respectively.

CONCLUSION

Higher volume of culture medium to load the embryo into the catheter during embryo transfer does not influence the clinical outcome in fresh IVF cycles.

TRIAL REGISTRATION NUMBER

NCT03350646.

Embryo transfer simulation improves pregnancy rates and decreases time to proficiency in Reproductive Endocrinology and Infertility fellow embryo transfers

OBJECTIVE

To design and evaluate an ET simulator to train Reproductive Endocrinology and Infertility (REI) fellows' techniques of ET.

DESIGN

Simulation model development and retrospective cohort analysis.

SETTING

Not applicable.

PATIENT(S)

Patients undergoing IVF.

INTERVENTION(S)

Simulation model evaluation and implementation of ET simulation training.

MAIN OUTCOME MEASURE(S)

Pregnancy rates.

RESULT(S)

The REI fellow and faculty evaluation responses (n = 19/21 [90%]) of the model demonstrated realistic characteristics, with evaluators concluding the model was suitable for training in almost all evaluated areas. A total of 12 REI fellows who performed ET were analyzed: 6 before ET trainer and 6 after ET trainer. Pregnancy rates were 31% in the initial 10 ETs per fellow before simulator vs. 46% after simulator. One of six pre-ET trainer fellows (17%) had pregnancy rates ≥40% in their first 10 ETs; whereas four of six post-ET trainer fellows had pregnancy rates ≥40% in their first 10 ETs. The average number of ETs to obtain >40% pregnancy efficiency was 27 ETs before trainer vs. 15 ETs after trainer. Pregnancy rates were similar in the two groups after 20 ETs, and collective terminal pregnancy rates were >50% after 40 ETs.

CONCLUSION(S)

Embryo transfer simulation improved REI fellow pregnancy rates in their first 10 transfers and led to a more rapid ET proficiency. These data suggest potential value in adopting ET simulation, even in programs with a robust history of live ET in fellowship training.

ASRM standard embryo transfer protocol template: a committee opinion

Standardization improves performance and safety. A template for standardizing the embryo transfer procedure is presented here with 12 basic steps supported by published scientific literature and a survey of common practice of SART programs; it can be used by ART practices to model their own standard protocol.

How do laboratory embryo transfer techniques affect IVF outcomes? A review of current literature

Over the last few years, many studies have focused on embryo selection methods, whereas little attention has been given to the standardization of the procedure of embryo transfer. In this review, several parameters of the embryo transfer procedure are examined, such as the: (i) culture medium volume and loading technique; (ii) syringe and catheters used for embryo transfer; (iii) viscosity and composition of the embryo transfer medium; (iv) environment of embryo culture; (v) timing of embryo transfer; (vi) and standardization of the embryo transfer techniques. The aim of this manuscript is to review these factors and compare the existing embryo transfer techniques and highlight the need for better embryo transfer standardization.

Embryo transfer by reproductive endocrinology fellows vs attending physicians: are live birth rates comparable?

OBJECTIVE

To compare live birth rates following ultrasound-guided embryo transfer (ET) by reproductive endocrinology and infertility fellows versus attending physicians.

STUDY DESIGN

Women who underwent their first day-3, fresh, nondonor ET between Oct. 1, 2005, and April 1, 2011, at our academic center were included in this retrospective cohort study. Embryos were designated high quality if they had 8 cells, less than 10% fragmentation, and no asymmetry. ET was performed with the afterload technique under ultrasound guidance. Categorical variables were evaluated with the χ(2) test and continuous variables with the Student t test. Logistic regression was performed to assess the relationship between ET physician and live birth rate while adjusting for potential confounders.

RESULTS

Seven hundred sixty women underwent ET by an attending physician, and 104 by a fellow. Baseline characteristics were similar between the groups. The live birth rate was 31% following ET by an attending physician, compared with 34% following ET by a fellow (P = .65). Logistic regression adjusting for potential confounders demonstrated no significant association between ET physician and live birth rate.

CONCLUSION

This retrospective study demonstrated no significant difference in live birth rates following ultrasound-guided ET by fellows vs attending physicians at our institution. These data suggest that academic practices using the afterload method and ultrasound guidance can train fellows to perform ET without compromising success rates.

Assessment of pregnancy-associated, within-woman change in uterine length

OBJECTIVE

To evaluate how absolute uterine length changes as a result of pregnancy.

METHODS

Longitudinal repeated-measures study of all women presenting to a university-affiliated clinic for uterine sounding prior to in vitro fertilization (IVF) who went on to deliver at term and return for repeat measurement from 2002 to 2012. Change in uterine length was assessed by the Wilcoxon signed-rank test.

RESULTS

Among 495 women, mean pregnancy-associated change in uterine length was 0.0 cm (SD ± 0.7, p = 0.84), with 31% of women experiencing no change and 75% of women experiencing a change ≤0.5 cm. Mean uterine lengths at pre-cycle and repeat measurement were 7.2 cm (SD ± 0.7) and 7.2 cm (SD ± 0.7) with medians of 7.0 cm (IQR 7.0-7.5) and 7.0 cm (IQR 6.8-7.8), respectively. Change in uterine length did not vary by gestational number or within time interval between measurements (all p > 0.5).

CONCLUSIONS

There was no difference in uterine length before and after term pregnancy. The finding of minimal variation in uterine length both across and within women suggests uterine length may be relatively stable such that patients undergoing IVF after term IVF pregnancy may not require repeat measurement. Future studies might assess pregnancy-associated sonographic changes in uterine volume and the relationship between uterine length and IVF outcomes.

Uterine length and fertility outcomes: a cohort study in the IVF population

STUDY QUESTION

What is the relationship between pre-cycle uterine length and IVF outcome (chemical pregnancy, clinical pregnancy, spontaneous abortion and live birth)?

SUMMARY ANSWER

Women at extremes of uterine length (<7.0 or >9.0 cm) were less likely to achieve live birth and women with uterine lengths <6.0 cm were also more likely to experience spontaneous abortion.

WHAT IS KNOWN ALREADY

A prospective study of 807 women published in 2000 found that implantation and clinical pregnancy rates were highest in women with uterine lengths between 7.0 and 9.0 cm, though the difference was not significant. The relationship between pre-cycle uterine length and live birth has not been evaluated.

STUDY DESIGN, SIZE, DURATION

A retrospective cohort study of all cycles performed after uterine length measurement at an academic hospital IVF clinic from 2001 to 2012.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 8981 fresh cycles were performed in 5120 adult women with normal uterine anatomy. Women with uterine anomalies (unicornuate, bicornuate, septate or uterus exposed to diethylstilbestrol) were excluded and women with fibroids were identified for subanalysis. Uterine length was measured by uterine sounding. Cycles were divided by uterine length into groups: <6.0 cm (very short, n = 76), 6.0-6.9 cm (short, n = 2014), 7.0-7.9 cm (referent, n = 4984), 8.0-8.9 cm (long, n = 1664) and ≥9 cm (very long, n = 243). Multivariate logistic regression (first-cycle analyses) and generalized estimating equations (all-cycle analyses) were adjusted for age, fibroids and ART treatment (assisted hatching, intracytoplasmic sperm injection) to generate relative risk (RR) of cycle outcomes by uterine length.

MAIN RESULTS AND THE ROLE OF CHANCE

Median uterine length in the IVF population was 7.0 cm (interquartile range 7.0-7.8) and was positively associated with BMI (P < 0.001) and fibroids (P = 0.02). Compared with the referent group, women with uterine lengths <6.0 cm were half as likely to achieve live birth (RR: 0.53; 95% confidence interval (CI): 0.35-0.81) and women with lengths of 6.0-6.9 cm were also less likely (RR: 0.91; CI: 0.85-0.98). Cubic regression spline identified a significant inverse U-shaped association whereby women with uterine lengths <7.0 or >9.0 cm were less likely to achieve live birth. Women with lengths <6.0 cm were also more likely to experience spontaneous abortion (RR: 2.16; CI: 1.23-3.78). Results remained consistent when excluding women with a uterine factor diagnosis (n = 8823), when limiting to the first cycle at our institution (n = 5120) and when further restricting to first-ever cycles (n = 3941).

LIMITATIONS, REASONS FOR CAUTION

Optimal assessment of uterine length by ultrasound was not feasible due to time and cost limitations, though uterine sounding is a clinically relevant measurement allowing for results with practical implications. Findings from our predominantly Caucasian clinic population may not be generalizable to infertile populations with different ethnic compositions.

WIDER IMPLICATIONS OF THE FINDINGS

Reproducibility of results would solidify findings and inform patient counseling in women undergoing IVF.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was sought for this investigation. MD declares relationships with UpToDate (royalties) and WINFertlity (consultant).

Correlation of technical difficulty during embryo transfer with rate of clinical pregnancy

AIM

To correlate the ease or difficulty of embryo transfer and blood at catheter tip with pregnancy rate when embryo transfer (ET) was performed by the same operator using soft catheter.

MATERIALS AND METHODS

A retrospective analysis of 342 patients who underwent in vitro fertilization or ICSI cycle from January 2008 to December 2010 in a single centre was done. The type of transfer was divided into two groups: 'easy' or 'difficult'. Transfer was considered difficult when additional instrumentation was required or firmer catheter was used or required changing of catheter. Patients undergoing cryo-preserved ET were excluded from the study.

RESULTS

On the day of transfer in 284 (83%) patients, ET was easy and difficulty was encountered in 58 (17%) patients. Blood at catheter was seen in 101 (29.53%) patients. In the group of 58 difficult transfers, 10 pregnancies resulted with a clinical pregnancy rate of 17.2%, while 67 pregnancies resulted in 284 cycles of easy transfer with clinical pregnancy rate of 23.6% (P value = 0.045). While no significant difference was seen in pregnancies with blood on outer catheter and blood less transfer, there was significant reduction in pregnancy rate when blood was present on catheter tip compared to bloodless transfer (13.3% v/s 24.1; P value = 0.032).

CONCLUSION

Reduction in clinical pregnancy rate is seen with difficult ETs, more when blood is present at the catheter tip.

Assisted reproduction outcomes after embryo transfers requiring a malleable stylet

OBJECTIVE

This retrospective case-control study was undertaken to assess the impact of a malleable stylet application on embryo transfer (ET) outcome.

METHODS

The Wallace malleable stylet was used when the soft inner catheter could not negotiate the internal os during ultrasound-guided ET. Patients having an age ≤37 years, with three embryos replaced were included in the analysis. Implantation rate, clinical pregnancy rate and live birth rate were the main outcome measures.

RESULTS

The Wallace malleable stylet was applied in 164 (29.6%) of the 553 ETs evaluated. Implantation rate, clinical pregnancy rate and live birth rate showed a 5.6% (19.4% vs. 13.8%), a 10.8% (41.9% vs. 31.1%) and a 9.9% (37.3% vs. 27.4%) absolute difference, respectively, in favor of ETs not requiring the stylet. These differences were statistically significant (P < 0.05).

CONCLUSIONS

ETs requiring stylet are associated with lower implantation, clinical pregnancy and live birth rates.

Use of Versapoint to refashion the cervical canal to overcome unusually difficult embryo transfers and improve in-vitro fertilization-embryo transfer outcome: A case series

BACKGROUND

Smooth atraumatic embryo transfer is paramount for the success of in-vitro fertilization (IVF). In difficult cases, cervical canal manipulation may be required.

AIM

To see if surgical correction of the cervical canal or cervical canal refashioning could improve ease of embryo transfer.

SETTING

Private infertility and IVF hospital.

DESIGN

Prospective study.

MATERIALS AND METHODS

PATIENTS

11 women with failed 1-3 IVF cycles with history of extremely difficult embryo transfers (ETs) despite undergoing cervical dilatation in the cycle prior to IVF.

INTERVENTIONS

Operative hysteroscopy using Versapoint for refashioning of the cervical canal.

MAIN OUTCOME MEASURES

Ease of ET in the subsequent IVF cycle. Secondary outcome measure was to assess reproductive outcome.

RESULTS

Easy and atraumatic ET in the IVF cycle after procedure in 100% patients. PR was 46.5%.

CONCLUSIONS

Use of Versapoint for refashioning the cervical canal can improve the quality of ET and PR.

Usefulness of statistics for establishing evidence-based reproductive medicine

During the last decade, evidence-based medicine has been described as a paradigm shift in clinical practice, and as "the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients". Appropriate statistical methods for analyzing data are critical for the correct interpretation of the results in proof of the evidence. However, in the medical literature, these statistical methods are often incorrectly interpreted or misinterpreted, leading to serious methodological errors and misinterpretations. This review highlights several important aspects related to the design and statistical analysis for evidence-based reproductive medicine. First, we clarify the distinction between ratios, proportions, and rates, and then provide a definition of pregnancy rate. Second, we focus on a special type of bias called 'confounding bias', which occurs when a factor is associated with both the exposure and the disease but is not part of the causal pathway. Finally, we present concerns regarding misuse of statistical software or application of inappropriate statistical methods, especially in medical research.

[Professional Practice Evaluation: How to improve quality management in procreation centers?]

OBJECTIVES

The Professional Practice Evaluation (PPE) is at the heart of quality management in procreation centers. Hereby, we report 3 years of EPP in Cytogenetics and Reproduction laboratory in Amiens University Hospital.

PATIENTS AND METHODS

This PPE is based upon prospective analysis of in vitro fertilization techniques regarding two major parameters: clinically in improving embryo transfer and biologically by determining fecundation levels. Clinical pregnancies in "Top Quality" trial is chosen as a major indicator of our results.

RESULTS

Per transfer, there is an increase of 8% for clinical pregnancies and 31% in "Top quality" trials.

DISCUSSION AND CONCLUSION

The improvement in our results allowed us to propose, in favourable conditions, single embryo transfer.

Quality Management Issues in the Assisted Reproduction Laboratory

In the United States, the Clinical Laboratory Improvement Act (CLIA) of 1988 describes requirements and guidelines for implementing a quality control/quality assurance (QC/QA) program for moderate and high complexity laboratories. These requirements and guidelines apply to Assisted Reproductive Technology (ART) laboratories as well. The general topic of QC and QA as it pertains to in vitro fertilization (IVF) and embryo transfer (ET) is extensively reviewed. This review summarizes many of the QC and QA events that contribute to the advancement of knowledge in this biotechnological field. These events include control of the culture environment inside and outside of the incubator, as well as factors that affect culture media. This review also discusses, in considerable detail, the QC and the QA that pertain to equipment used within the laboratory and how to control for potential contaminants, which reside within the laboratory. This review provides evidence to indicate the need for laboratory personnel to monitor quality improvement issues on a continuous basis. Personnel must be willing to change as improvements in technology occur in order to meet the ever-evolving demands of a more difficult patient population. Suggestions for meeting these demands are offered.

Treatment with oxytocin antagonists before embryo transfer may increase implantation rates after IVF

This report aimed to examine the effects of atosiban on pregnancy outcome after IVF-embryo transfer. A prospective, randomized, placebo-controlled clinical study was performed. A total of 180 women undergoing intracytoplasmic sperm injection who had top-quality embryos were randomly allocated into treatment and control groups. All the patients had infertility due to tubal factor, hormonal-anovulatory disorders, male factor or unexplained reasons. The treatment group received intravenous administration of atosiban before embryo transfer with a total administered dose of 37.5 mg. In the control group, the same number of cycles was performed with placebo medication. The clinical pregnancy rate (PR) per cycle and implantation rate (IR) per transfer were 46.7% and 20.4% in the atosiban-treated group, which were significantly higher than in the control group (28.9% and 12.6%, respectively, P=0.01). The miscarriage rates of groups 1 and 2 were 16.7% and 24.4%, respectively (P=0.01). These results have indicated that atosiban increases the IR and PR after IVF-embryo transfer. These results suggest that atosiban treatment before embryo transfer is effective in priming of the uterus for implantation. This is the first study to investigate the possible contributions of atosiban for improving the PR after IVF-embryo transfer.

Assisted reproductive technologies in public and private clinics

The aim of this study was to analyse the influence of the type of service provided by assisted reproduction clinics. The activities, treatment patterns and results achieved by assisted reproduction centres in Spain were examined, comparing public and private clinics. A retrospective study was carried out using the Assisted Reproductive Technology Register of the Spanish Fertility Society for 2002-2004. The results showed that 74%, 96% and 99% of IVF/intracytoplasmic sperm injection, oocyte donation and preimplantation genetic diagnosis cycles, respectively, were carried out in the private sector. Public clinics performed proportionally more transfers of three embryos than the private clinics (48.1% versus 41.7%). More elective transfers were performed in private clinics. Pregnancy rates per cycle started, per puncture and per transfer were significantly higher among private than public clinics (29.1%, 32.7% and 35.9% versus 25.2%, 28.5% and 32.6%, respectively) (P < 0.05). Implantation rate has risen year on year in both types of clinic and was significantly higher (P < 0.05), every year, among the private clinics. The multiple-pregnancy rate was significantly higher among the private clinics (30.8% versus 26.4%) (P < 0.05). In conclusion, differences exist between public and private clinics as regards to their volume of activity, the range of services offered, clinical practice and results achieved.