Optimizing the embryo transfer technique

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.

Four-dimensional ultrasound guided embryo transfers improve live birth rates when compared to the clinical touch technique: a randomised controlled trial

Most aspects of in-vitro fertilisation (IVF) have changed dramatically since introduction, but embryo transfer (ET) technique remains largely unaltered. We aimed to determine whether four-dimensional ultrasound guided embryo transfers (4D UGET) could improve pregnancy rates when compared with clinical touch technique (CTT). This was a single centre open labelled randomised controlled trial in a tertiary fertility centre in the UK. 320 women were randomised on the day of single ET. The primary outcome was clinical pregnancy rate (CPR), secondary outcomes included live birth rate (LBR), biochemical pregnancy rate (BPR), miscarriage, pregnancy of unknown location (PUL) and ectopic pregnancy. 4D-UGET resulted in significantly higher CPR [50% vs 36% p = 0.02, OR 1.78 (1.12-2.84)] and LBR [41% vs 28%, p = 0.02, OR 1.77 (1.09-2.87)] when compared to CTT technique. Miscarriage (p = 0.49), PUL (p = 0.14) and ectopic pregnancy (p = 0.96) were similar between the two groups. LBR, from this trial, are significantly higher than the current UK average (41% vs 24%). 4D UGET allows for superior imaging of the uterine cavity, whilst tailoring the embryo deposition point specifically to the patient. Further RCTs are required to determine if these results can be replicated in other units and whether 4D UGET is superior to 2D UGET.

Comparison of pregnancy outcomes of cervical mucus washing with physiologic saline solution or G-Rinse medium solution, in elective single-embryo transfers

AIM

To compare the pregnancy outcomes between physiologic saline and G-Rinse medium solution for cervical mucus washing, in fresh elective single-embryo transfers (ET) in women under the age of 37.

MATERIAL AND METHODS

This was a retrospective data analysis performed in a single in vitro fertilization (IVF) center between February 2018 and November 2021. Women younger than 37 years who underwent single elective ET were included and all women had anti-Mullerian hormone (AMH) levels ≥ 1.5 ng/ml. Age, body mass index (BMI), AMH levels, and pregnancy outcomes as clinical pregnancy rate (CPR) and live birth rate (LBR) were analyzed.

RESULTS

Study population consisted of 75 women in the G-Rinse medium solution group and 97 women in the physiologic saline group. Clinical pregnancy rate was 58.7% and 61.9% in the G-Rinse medium solution group and saline group, respectively (p = 0.673), and LBR was calculated as 41.3% and 47.4% in the G-Rinse medium solution group and saline group, respectively (p = 0.430). A log-binomial regression model was used and the model was adjusted for BMI to evaluate the effect of the cervical mucus washing method on the pregnancy outcomes. There was an estimated 5% decrease in the relative risk for CPR in the G-Rinse medium solution group compared to the saline group (95% CI: 0.74 to 1.2, p = 0.673). There was an estimated 13% reduction in the relative risk for LBR in the G-Rinse medium solution group compared to the saline group (95% CI: 0.62 to 1.23, p = 0.430). They were both statistically not significant.

CONCLUSION

In our study, the replacement of using G-Rinse medium solution to physiologic saline solution for cervical cleaning did not change CPR and LBR outcomes. Using physiologic saline solution can be a good alternative approach for ectocervical washing during embryo transfer in selected population because of its lower costs, easy accessibility, and common use.

First deliveries of felines by transcervical transfer of in vitro-cultured embryos

Transcervical transplantation of embryos has been wildly used in several species. However, it has not been successful in feline species because of their unique cervix structure combined with poor in vitro culture systems for embryos. In the present study, a simple device to guide the embryo transfer (ET) tube through the cervix and into the uterus was developed. To supply better blastocysts for ET, the in vitro culture system of feline embryos was also optimized. Results showed that 91.67 ± 4.17% of embryos developed to the blastocyst stage in QAU-4 medium compared with 49.17 ± 6.51% in KSOM medium. The total cell number of blastocysts reached 87.1 ± 22.1 in QAU-4 medium compared with 29.8 ± 2.1 in KSOM. Embryoid body formation was also observed in QAU-4 medium. Finally, by the improved technical scheme, CRX (Cone-Rod Homeobox) gene-edited kittens were successfully bred. To date, this is the first report, to our knowledge, of knockout kittens successfully delivered after transcervical ET with a simple transfer tube.

Effects of embryo retention during embryo transfer on IVF outcomes

PROPOSE

To investigate embryo retention (ER) rate in embryo transfer (ET) cycles and its effects on reproductive outcomes in a large database.

METHODS

A matched retrospective cohort study in a tertiary academic hospital-based reproductive center. A total of 15,321 ET cycles were performed from January 2008 to December 2018. Each woman was matched with three separate control subjects of the same age (± 1 year), embryo condition, main causes of infertility, and type of protocol used for fresh or frozen ET cycles. The main outcomes were ER rate, and implantation, clinical pregnancy, ectopic pregnancy, and live birth rates.

RESULTS

The overall incidence of ER was 1.4% (213/15,321). There was no difference in the rate of ER rate in fresh ET cycles compared with frozen transfer cycles (P = 0.54). We matched 188/213 (88%) of cases in the ER group to 564 non-ER cases. There were no cases of the blood in the catheter seen in the ER group. Pregnancy outcomes were similar between the ER and the non-ER cycles: clinical pregnancy rate (31.3% vs. 36.1%, P = 0.29), implantation rate (26.2% vs. 31.3%, P = 0.2), live birth rate (20.3% vs. 24%, P = 0.53), ectopic pregnancy rate (0.5% vs. 0.4%, P = 0.18), and miscarriage rate (10.7% vs. 11.3%, P = 0.53).

CONCLUSION

Our results suggest that ER rate does not affect the reproductive outcomes including clinical pregnancy rate, implantation rate, and live birth rate. Patients and physicians should not be concerned about the retention of embryos during transfer since there is no effect on pregnancy outcome.

Does rotation during catheter withdrawal in embryo transfer increase pregnancy rates?

BACKGROUND

The aim of this study was to determine whether there is a difference in pregnancy rates between groups that we removed directly and removed by rotating the embryo transfer catheter 360°.

METHODS

The study group consisted of 552 patients who were withdrawn by 360° rotation and 797 patients who were withdrawn without catheter rotation. All patients underwent one or two fresh ETs on day 3 or 5. Groups were compared in terms of cycle characteristics and clinical pregnancy rates.

RESULTS

There were no significant differences in demographic and clinical characteristics of both groups, such as age, body mass index (BMI), duration of infertility, causes of infertility, and basal hormone levels. Clinicals pregnancy rate, in the study group, 48% (265/552) and in the control group, 50.8% (405/797) were similar in both groups. When the implantation rate and miscarriage rate were examined, both groups were found to be similar.

CONCLUSION

It was found that 360° rotation while pulling catheter during embryo transfer had no effect on pregnancy and clinical pregnancy.

The Role of Transvaginal Ultrasound Guided Embryo Transfer to Improve Pregnancy Rate in Obese Patients Undergoing Intracytoplasmic Sperm Injection

Objective

To evaluate the effectiveness of transvaginal ultrasound (TVUS) versus the transabdominal ultrasound (TAUS) guided embryo transfer (ET) in obese patients undergoing Intracytoplasmic sperm injection (ICSI).

Design

A prospective randomized controlled trial.

Setting

University hospital.

Patient(s)

Eight hundred participants with BMI ≥30 received the long agonist protocol. They were randomized into 2 equal groups of 400 patients. Each group had either TAUS guided ET or TVUS guided ET.

Main Outcome Measure(s)

Our primary outcomes were clinical pregnancy rate, degree of patient pain assessed by visual analogue scale (VAS). The secondary outcomes were live birth rate, implantation rate, miscarriage and chemical pregnancy rates, duration of ET.

Result(s)

Our results showed a significant higher chemical and clinical pregnancy rates in the TVUS group in comparison to TAUS group (45.3% vs. 38.3%, p=0.045) and (37.8% vs. 30.8%, p=0.044) respectively. There was tendency for increased live birth rates in the TVUS group however it did not reach statistical significance (50.2% vs. 44.8%). The VAS of the pain was significantly less in TVUS group in comparison to the TAUS group (2.1 ±0.7 vs. 4.5 ±1.3), also abdominal discomfort was significantly less in TVUS group in comparison to the TAUS group (13% vs. 58%) p= value 0.0001.

Conclusion(s)

This study showed superior role of TVUS guided ET over TAUS regarding less pain and better pregnancy and live birth rates in obese participants.

Clinical Trial Registration Number

Clinical trial. Gov identifier NCT03473028.

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.

Ultrasound guidance versus the classical method for intrauterine insemination in oral medication-stimulated cycles: A randomized, single-blind, controlled trial

OBJECTIVE

This study was conducted to compare the pregnancy rates of ultrasound-guided intrauterine insemination (UG-IUI) and classical intrauterine insemination (C-IUI) cycles.

STUDY DESIGN

A total of 320 infertile women were enrolled and randomized into an UG-IUI group, and a C-IUI group. All participants received an oral medication for ovarian stimulation. With both groups, the IUIs were scheduled and performed by doctors in their residency and fellowship training, under supervision. The duration and difficulty of the procedures were assessed. A pregnancy test was offered 3 weeks later if the participants did not have menstruation.

RESULTS

The demographic and other baseline characteristics of the groups (baseline hormone levels, cervical length, uterine position, endometrial thickness, and expertise of the providers) were comparable. The pregnancy rates were similar, with 6.9 % and 6.3 % for the UG-IUI and C-IUI groups, respectively. In the UG-IUI group, the pregnancy rate of the multigravida women was three times higher than that of the nulligravida women (15.4 % vs. 5.0 %; p = 0.13). Although the duration of the procedure was shorter for the UG-IUI group (p < 0.05), the level of difficulty was similar for the two groups.

CONCLUSIONS

For oral-medication stimulated cycles, UG-IUI did not increase the pregnancy rate more than with C-IUI. However, the pregnancy rate tended to increase with UG-IUI for multigravida women.

The effects of diagnostic hysteroscopy on the reproductive outcomes of infertile women without intrauterine pathologies: a systematic review and meta-analysis

Purpose

Hysteroscopy can be used both to diagnose and to treat intrauterine pathologies. It is well known that hysteroscopy helps to improve reproductive outcomes by treating intrauterine pathologies. However, it is uncertain whether hysteroscopy is helpful in the absence of intrauterine pathologies. This study aimed to confirm whether hysteroscopy improves the reproductive outcomes of infertile women without intrauterine pathologies.

Methods

We conducted a systematic review of 11 studies retrieved from Ovid-MEDLINE, Ovid-Embase, and the Cochrane Library. Two independent investigators extracted the data and used risk-of-bias tools (RoB 2.0 and ROBINS-I) to assess their quality.

Results

Diagnostic hysteroscopy prior to in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) was associated with a higher clinical pregnancy rate (CPR) and live birth rate (LBR) than non-hysteroscopy in patients with recurrent implantation failure (RIF) (odds ratio, 1.79 and 1.46; 95% confidence interval, 1.40–2.30 and 1.08–1.97 for CPR and LBR, respectively) while hysteroscopy prior to first IVF was ineffective. The overall meta-analysis of LBR showed statistically significant findings for RIF, but a subgroup analysis showed effects only in prospective cohorts (odds ratio, 1.40 and 1.47; 95% confidence interval, 0.62–3.16 and 1.04–2.07 for randomized controlled trials and prospective cohorts, respectively). Therefore, the LBR should be interpreted carefully and further research is needed.

Conclusion

Although further research is warranted, hysteroscopy may be considered as a diagnostic and treatment option for infertile women who have experienced RIF regardless of intrauterine pathologies. This finding enables nurses to educate and support infertile women with RIF prior to IVF/ICSI.

Predictive factors influencing pregnancy rate in frozen embryo transfer

PURPOSE

To evaluate the outcomes of embryo transfer (ET) and to identify the parameters influencing pregnancy outcomes.

METHODS

This study included 938 ET cycles involving single frozen and thawed good-quality blastocyst (Gardner grade ≥3BB) between August 2017 and January 2018. The significance of several parameters including endometrial thickness, position of the transferred air bubble, self-evaluation score by physicians, and uterus direction at ET as predictors of clinical pregnancy was evaluated using univariate and multivariate analyses.

RESULTS

Among 938 ET cycles, 462 (49.3%) resulted in a clinical pregnancy. Endometrial thickness was positively associated with clinical pregnancy in a linear trend. Between the variable position of the transferred air bubble and clinical pregnancy rate showed a curvilinear relationship. Clinical pregnancy rate was higher in cases with good self-evaluation score, whereas there was no difference between groups with different uterus directions. Univariate analysis of predictive parameters identified endometrial thickness, self-evaluation score by physicians, and position of air bubbles as significant predictors of clinical pregnancy, of which endometrial thickness and position of air bubbles appeared to be independently related to clinical pregnancy.

CONCLUSION

Endometrial thickness and the position of transferred air bubbles influenced clinical pregnancy in ET cycles.

The Influence Of Intrauterine Pressure On Embryo Retention In A Catheter After Embryo Transfer

The retention of the embryo in the transfer catheter after embryo transfer (ET) during in vitro fertilization is a very common phenomenon, encountered by even the most experienced operators, and embryos retained in the transfer catheter or its sleeve require a repeat transfer. The exact mechanism of embryo retention has not been explained. Therefore, the present study aimed to investigate the mechanism of embryo retention in the catheter during embryo transfer by using a transparent uterus model equipped with pressure sensors and a video recorder. The results indicate that pressure changes in the uterine cavity during ET can influence the distribution of the transferred fluid containing the embryo. Under certain conditions, the transferred fluid can flow backward in the catheter, which may lead to retention of the embryo in the catheter.

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.

Establishment of a trans-vaginal ultrasound-guided pinpoint transfer method

Purpose

Through the use of the trans‐vaginal ultrasound‐guided pinpoint transfer method, the aim was to ensure the safety of the embryo being transferred in cases of difficult cervixes. It also was aimed to be able to stop embryo transfers in difficult cases and to be able to restart the process under anesthesia or cryopreservation.

Methods

A new type of transfer catheter was developed. With this method, after reaching the internal os, the embryologist begins the loading of the embryo into the inner catheter. Then, the embryo transfer begins. Under the guidance of the trans‐vaginal ultrasonography, the optimal position for implantation is selected.

Results

Out of 666 cases, 14 were difficult cervixes. This transfer method enabled 221 of the 666 patients to become pregnant successfully, which was a success rate of 33.2%.

Conclusion

From start to finish, this method takes only 2 min. It is simple, fast, and reliable, with a high satisfaction rate amongst patients.

Difficult Embryo Transfer: A Systematic Review

We performed a systematic review on the clinical epidemiology and outcome of difficult embryo transfers (ETs) in infertility patients who present with difficult ET. We searched PubMed, ScienceDirect, and Elsevier journals from 1980 to June 2017. We aimed to determine the most successful method resulting in highest pregnancy rates (PRs) in patients with difficult ET. We identified 50 articles, in which 36 were reviewed and 15 were included. Analysis of the data collected showed that the majority of the difficult ETs were caused by cervical stenosis and the most common treatment was cervical dilation. We concluded that cervical dilation was effective at managing difficult ET. Hegar dilators used a minimum of 3 weeks before ET showed to have higher PR.

Cervical mucus removal prior to intrauterine insemination: a randomized trial

OBJECTIVE

To detect if removing the cervical mucus before performing intrauterine insemination (IUI) could improve pregnancy outcomes in patients with unexplained infertility.

DESIGN

Prospective randomized study.

SETTING

An Egyptian University Hospital.

POPULATION

Seven hundred and fourteen couples with unexplained infertility who underwent intrauterine insemination (IUI) with or without cervical mucus removal.

METHODS

Using computer-generated numbers, patients were randomly allocated to cervical-mucus-removal (removed from both internal and external os) or non-mucus-removal groups. Only participants were blinded as to group assignment.

MAIN OUTCOME MEASURES

The clinical pregnancy rate.

RESULTS

Of 714 IUI patients between November 2014 and March 2017, 361 were in the mucus removal group, and 353 in the non-mucus-removal group. Difficult catheterization was encountered in 17 cases out of 666 (2.6%) 12 in the cervical-mucus-removal group and five in the non-mucus-removal group). A total of 666 IUI cycles were completed while 48 were either cancelled or lost in their follow-up. The clinical pregnancy rate was significantly higher in the mucus-removal group [31.0% (n = 112)] than in the non-mucus-removal group [21.8% (n = 77); P = 0.005]. Ovarian hyperstimulation developed in 33 (4.6%) cases: 18 cervical mucus-removal and 15 non-mucus-removal. All except one were mild and managed with outpatient care.

CONCLUSIONS

Cervical mucus removal before IUI could improve pregnancy outcomes in women with unexplained infertility.

TWEETABLE ABSTRACT

Cervical mucus removal before IUI can improve pregnancy outcomes.

Correlation of Site of Embryo Transfer with IVF Outcome: Analysis of 743 Cycles from a Single Center

OBJECTIVE

To investigate the influence of site of embryo transfer (ET) on reproductive outcome.

MATERIALS AND METHODS

A retrospective analysis of 743 ultrasound-guided ET in fresh in vitro fertilization (IVF) cycles from a single center over a period of 4 years was conducted. The distance between the fundal endometrial surface and the air bubble was measured, and accordingly, patients were divided into four groups (≤10 mm; >10 and ≤15 mm; >15 and 20 mm; >20 and <25 mm).

SETTING

Tertiary Assisted Reproductive Technology (ART) center.

PATIENTS

All patients enrolled in the IVF program undergoing ET.

INTERVENTIONS

Controlled ovarian hyperstimulation (OS), IVF, and ET.

MAIN OUTCOME MEASURES

Cleavage rate and clinical pregnancy rate.

RESULTS

Clinical pregnancy rate was significantly more in groups 2 and 3 compared to the other groups. Logistic regression analysis showed that one unit increase in embryos transfer will enhance the pregnancy outcome about 3.7 (adjusted odds ratio) times with 95% confidence limits 2.6 to 5.4. Similarly, pregnancy outcome will be 3.1 (95% confidence limits: 1.5-6.4) times higher for distance group >15 and <20 mm compared to less than 10-mm distance group. Ectopic pregnancy rates were similar in all the four groups.

CONCLUSION

The present study demonstrates that site of ET has significant difference on reproductive outcome.

Evaluation of the cervix tissue homogeneity by ultrasound elastography in infertile women for the prediction of embryo transfer ease: a diagnostic accuracy study

BACKGROUND

Ultrasound elastography is a non-invasive medical imaging technique able to quantitatively characterize the stiffness of a given tissue. It has been shown to predict the risk for cervical insufficiency and preterm delivery, and to allow differentiation of malignancy from normal tissue. The present study sought to evaluate whether cervical tissue dishomogeneity, as assessed by cervical ultrasound elastography, may predict the embryo transfer (ET) ease in infertile women undergoing IVF/ICSI.

METHODS

We evaluated 154 infertile patients with no history of previous ET or intrauterine insemination. Cervical stiffness was evaluated in six regions of interest (ROI), compared two by two to obtain strain ratio (SR) values. Since a SR value of 1 was suggestive of tissue homogeneity, we computed 1-SR/SR-1 values to obtain a measure of the degree of cervical tissue dishomogeneity that we named "dishomogeneity index" (DI). Ultrasound-guided ET was performed by an expert operator blinded to the results of cervical elastography. The prediction ability of elastography on ET ease was evaluated by binary logistic regression, and the predictive accuracy of the independent variables was quantified with area under the curve (AUC) estimates derived from receiver operating characteristic (ROC) curve.

RESULTS

ET resulted to be easy in 99 out of 154 patients (64,2%), difficult in 54 patients (35%), and impossible in one. DI values in cervical medial lips region correctly classified 86.9% of patients, according to binary logistic regression, with a sensitivity of 81.4% and a specificity of 89,9%, positive likelihood ratio (LR) 8.07 and negative LR of 0.21. A DI cut-off value of 0.29 predicted a difficulty of ET with a sensitivity of 88,9% and a specificity of 85%.

CONCLUSIONS

Cervical ultrasound elastography, by allowing the identification of cervical tissue dishomogeneity, may be of help in predicting the ET ease in infertile women candidates to IVF/ICSI.

Transvaginal ultrasound-guided embryo transfer in IVF

OBJECTIVES

To determine whether transvaginal ultrasound-guided embryo transfer is a technique that can be used routinely, whether it improves IVF outcomes and whether it makes difficult transfers easier and more successful.

MATERIAL AND METHOD

Non-randomized retrospective study conducted between 2012 and 2016 in the fertility center of the Diaconesses-Croix St-Simon hospital group. The outcomes of 3910 transfers, performed by 5 senior operators, under transabdominal ultrasound guidance are compared with those of 800 transfers, performed by 1 senior operator under transvaginal ultrasound guidance. The criteria studied are the feasibility of the technique and the percentage of pregnancies per transfer in the two populations described, as well as in the difficult and very difficult transfer populations.

RESULTS

All the transfers were feasible under transvaginal ultrasound guidance without the use of forceps or additional instruments. The percentage of pregnancies per transfer is significantly increased, when the transfer is performed under transvaginal ultrasound guidance compared with that performed under transabdominal ultrasound guidance, in the general population (38%, n=800 vs 30%, n=3910; P 0.0004) and in the reference population characterized by age <38 years and >6 oocytes collected per puncture (45%, n=490 vs 36%, n=1968; P 0.002). The percentage of pregnancies per transfer (P/T) is not significantly different in the populations of easy transfers (n 695, 38% P/T), difficult transfers (n 58, 46% P/T; P=ns) and very difficult transfers (n 47, 34% P/T; P=ns).

CONCLUSIONS

Embryo transfer is a key stage in IVF, in which the quality of performance determines the outcome. In this study, transvaginal ultrasound guidance of the transfer, which is the reference procedure in gynaecological imaging, significantly increases the percentage of pregnancies per transfer, both in the general population and in the reference population, compared with transfers performed under transabdominal ultrasound guidance. Transvaginal ultrasound facilitates the performance of difficult transfers and in particular achieves outcomes in these situations that are not significantly different from those of easy transfers. Visual monitoring of transcervical passage, which is rendered more precise and less traumatic and precision of embryo deposition are the factors that probably account for the improvement in outcomes.

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.

Reproductive outcomes of retransferring retained embryos in blastocyst transfer cycles

Objective

To determine the incidence of embryo retention (ER) in the transfer catheter following embryo transfer (ET) in blastocyst transfer and investigate whether retransferring retained embryos has an impact on reproductive outcomes in patients undergoing in vitro fertilization-ET.

Methods

We retrospectively analyzed the records of 1,131 blastocyst transfers, which comprised 223 single blastocyst transfer (SBT) and 908 double blastocyst transfer (DBT) cycles. Each SBT and DBT group was classified depending on whether ET was performed without retained embryos in the catheter during the first attempt (without-ER group) or whether any retained embryos were found following ET (ER group) for the purpose of comparing reproductive outcomes in a homogenous population.

Results

The overall incidence of finding retained embryos was 2.8% (32/1,131). There were no retained embryos in SBT cycles. In DBT cycles, implantation rates (30.0% vs. 26.6%), positive β-hCG rates (57.2% vs. 56.2%), clinical pregnancy rates (45.3% vs. 46.9%), and live birth rates (38.9% vs. 43.8%) were not significantly different between the without-ER and ER groups. There were no significant differences in the mean birth weight (g) 2,928.4±631.8 vs. 2,948.7±497.8 and the mean gestational age at birth (269.3±17.2 days vs. 264.2±25.7 days). A total of nine cases of congenital birth defects were found in this study population. Eight were observed in the without-ER group and one in the ER group.

Conclusion

Our results suggest that retransfer of retained embryos does not have any adverse impact on reproductive outcomes in blastocyst transfer cycles. Furthermore, our results support finding that SBT might be advantageous for decreasing the incidence of retained embryos in catheters.

The effect of embryo catheter loading technique on the live birth rate

Objective

Embryo loading (EL) is a major step in embryo transfer (ET) and affect on the success of in vitro fertilization (IVF). This study aimed to compare the effect of two different EL techniques on the rates of pregnancy and delivery in IVF/ET cycles.

Methods

207 fresh ET and 194 Frozen-thawed ET (FET) cycles were included in this retrospective study. Two groups (A and B) were defined based on the EL technique used. In group A, the entire catheter was flushed with Ham's F-10 medium. The embryos were then drawn into the catheter using one air bracket. In group B, 70 µL of air was aspirated into the syringe and the catheter was flushed using Ham's F10 medium. The medium, air, embryos, air, and finally another layer of medium were then sequentially drawn into the catheter. The main outcome measures were the pregnancy and delivery rates.

Results

The groups did not differ with respect to the etiology of infertility, the source of spermatozoa, the quality of the embryos, the type of EL catheter, and the ease of transfer. The pregnancy rate was similar between two groups. In fresh ET cycles, a higher delivery rate was observed in group B than it group A (78.1% vs. 60%, p=0.1). In FET cycles, the rate of delivery was significantly higher in group B than in group A to a nonsignificant extent (88.9% vs. 58.8%, p=0.06).

Conclusion

EL techniques did not have a significant impact on the delivery rate in either fresh or FET cycles.

Does prior hysteroscopy affect pregnancy outcome in primigravid infertile women?

OBJECTIVE

An increasing proportion of infertile women are subjected to hysteroscopy. The effect of hysteroscopy on the pregnancy rate in assisted reproduction has been demonstrated to be favorable, but cervical dilation in the course of hysteroscopy may have an adverse effect on pregnancy outcome. We sought to investigate the effect of hysteroscopy on the risk of early miscarriage, preterm delivery, low birthweight, and other complications of pregnancy.

STUDY DESIGN

This was a longitudinal retrospective cohort study at a university hospital. Data of 654 first-time singleton pregnancies between January 1997 and March 2011 in women with primary infertility were retrieved from a prospective data collection. Four cohorts were constructed based on exposure to hysteroscopy and pregnancy outcome (early miscarriage vs live birth). The primary endpoint was the duration of pregnancy at 37 weeks. Pregnancy outcomes of 167 infertile patients exposed to cervical dilation and hysteroscopy were compared with those of 327 infertile women unexposed to hysteroscopy.

RESULTS

The incidence of miscarriage, preterm birth, placenta previa, and premature rupture of membranes after maternal exposure to hysteroscopy was similar to that in women not exposed.

CONCLUSION

Prior hysteroscopy in infertile women does not affect subsequent pregnancy outcome.

Hysteroscopy in patients with repeated implantation failure improves the outcome of assisted reproductive technology in fresh and frozen cycles

AIM

Repeated implantation failure (RIF) is still a problem for many patients and their physicians. Some interventions have been practiced to overcome the problem; one is uterine cavity assessment before assisted reproductive technology (ART) cycles. This study aimed to evaluate the effect of hysteroscopy in women experiencing recurrent implantation failure with apparently normal uterine cavity before assisted reproductive techniques.

MATERIAL AND METHODS

This was a cohort study with historical controls conducted in a university hospital. A total of 353 women with RIF undergoing ART with normal hysterosalpingography and transvaginal ultrasound were evaluated. The intervention group underwent hysteroscopy with a rigid, 30°, 4-mm hysteroscope in the menstrual cycle just before ART; in the control group hysteroscopy was not performed. Basal characteristics, stimulation parameters and pregnancy rates were compared between the two groups.

RESULTS

Chemical pregnancy occurred in 58.5% of women in the hysteroscopy group versus 34.1% of control women (odds ratio [OR]: 2.7; 95% confidence interval [CI]: 1.7-4.2; P < 0.001). Clinical pregnancy occurred in 50.7% and 30.3% of women in the hysteroscopy and control groups, respectively (OR: 2.4; 95%CI: 1.5-3.7; P < 0.001). Delivery rate was 35.5% in hysteroscopy women and 21.1% in control women (OR: 1.9; 95%CI: 1.2-3.1; P = 0.008). The results of hysteroscopy were normal in 103 women (72.5%), and they revealed inflammation in 22 (15.5%), polyp in 16 (11.3%) and Asherman syndrome in one patient (0.7%).

CONCLUSIONS

Hysteroscopy in the menstrual cycle before ovarian stimulation in fresh cycles and before endometrial preparation in frozen thawed cycles in women experiencing recurrent implantation failure with apparently normal uterine cavity significantly increases the pregnancy rates in fresh and frozen cycles, respectively.

Successful twin delivery following transmyometrial embryo transfer in a patient with a false uterine cavity

A successful pregnancy is the greatest goal for reproductive medicine. The probability that pregnancy occurs during a cycle of assisted reproduction is a function of multiple factors, of which embryo transfer is one of the most critical steps in these treatments. This article reports a case of successful pregnancy and twin delivery by transmyometrial embryo transfer after IVF in a woman with a neocavity parallel to the uterine cavity, which prevented the transfer of embryos to the correct place. The patient first went to another fertility centre where embryo transfer was impossible to perform because the cervix could not be canalized. Subsequently in this study clinic, after considering the difficulty of inserting a catheter into the endometrial cavity, a trial transfer was performed, which discovered a false route parallel to endometrial cavity. Following a first cycle in which conventional transcervical embryo transfer was performed, a transmyometrial embryo transfer was carried out and the patient became pregnant with twins. In cases where transcervical embryo transfer is very difficult or impossible to perform, the value of transmyometrial transfer is self-evident.

The Impact of the Depth of Embryo Replacement into the Uterine Cavity under Transabdominal Ultrasound Guidance on In Vitro Fertilization and Embryo Transfer Outcome

Aim: The aim of the present study was to determine the importance of the depth of embryo replacement into the uterine cavity (upper or lower half endometrial cavity) on the implantation clinical pregnancy rates.Material and Methods: In this prospective observational were included 160 patients underwent controlled ovarian hyperstimulation followed by IVF/ICSI and embryo transfer. On the day of embryo transfer under direct transabdominal ultrasound guidance, the transfer catheter was advanced to a defined distance from the uterine fundus, up to the point estimated for transfer: 10 ± 2.5 mm (Group A) and 15 ± 2.5 mm (Group B).Results: In total, 160 patients, aged 24-42 years were included in the study. Overall clinical pregnancy rate were 41.2%. Analysis of our results demonstrated that pregnancy rate is significantly influenced by transfer distance from the fundus where the  pregnancy rate decreases from 48.7% in group B to 34.5%  in group A (p<0.05). There was not significantly difference in abortion rate between the two groups.Conclusion: In conclusion, our results suggest that depth of embryo replacement inside the uterine cavity may influence the pregnancy rates and should be considered as an important factor to improve the success of IVF cycles.

Prediction of embryo implantation potential by mass spectrometry fingerprinting of the culture medium

This study has evaluated the performance of a multivariate statistical model to predict embryo implantation potential by processing data from the chemical fingerprinting of culture medium samples used for human embryo culture. The culture medium for 113 embryos from 55 patients undergoing ICSI was collected after embryo transfer. The samples were split into positive (n=29) and negative (n=84) implantation groups according their implantation outcomes (100% or 0% implantation). The samples were individually diluted and analyzed by electrospray ionization mass spectrometry (ESI-MS). The m/z ratios and relative abundances of the major ions in each spectrum were considered for partial least square discriminant analysis. Data were divided into two subsets (calibration and validation), and the models were evaluated and applied to the validation set. A total of 5987 ions were observed in the groups. The multivariate statistical model described more than 82% of the data variability. Samples of the positive group were correctly identified with 100% probability and negative samples with 70%. The culture media used for embryos that were positive or negative for successful implantation showed specific biochemical signatures that could be detected in a fast, simple, and noninvasive way by ESI-MS. To our knowledge, this is the first report that uses MS fingerprinting to predict human embryo implantation potential. This biochemical profile could help the selection of the most viable embryo, improving single-embryo transfer and thus eliminating the risk and undesirable outcomes of multiple pregnancies.

Chelidonium majus and its effects on uterine contractility in a perfusion model

OBJECTIVE

The herbal agent celandine is thought to have mainly spasmolytic effects, but in the uterus it is regarded as promoting contractions, which can offer promising and innovative options for optimizing artificial reproduction. The aim of the present study was to investigate the effect of celandine on the uterine muscle, using a perfusion model of swine uteri.

STUDY DESIGN

Sixteen swine uteri were perfused with Krebs-Ringer solution. Celandine (Chelidonium, Paverysat; Johannes Bürger Ysatfabrik Ltd., Bad Harzburg, Germany) was administered at increasing dosages. Intrauterine pressure (IUP) was recorded using an intrauterine double-chip microcatheter (Urobar 8 DS-F, Raumedic, Rehau AG & Co., Rehau, Germany). Differences in pressure (ΔP) and area under the curve (ΔAUC) after drug administration in the uterine body and uterine horn in the various dilution series were noted. A paired Student's t-test was used to evaluate differences between groups, with significance set at P<0.05.

RESULTS

A significant initial increase in uterine activity was visible at each dosage. Inhibition of uterine activity was seen over longer periods of 5 and 10 min, particularly for a medium-dose range of 1-2mg/ml. At a dosage of 2mg/ml in particular, celandine almost always led to significant values.

CONCLUSION

Following intra-arterial administration in a swine uterus perfusion model, celandine initially causes a significant increase in contractility, which is followed over time by a relaxation phase. This suggests interesting hypotheses on whether Chelidonium majus might be used to promote targeted sperm transport.

The use of ultrasound during intrauterine insemination in unexplained infertility may improve pregnancy outcomes

OBJECTIVE

To investigate the role of ultrasound guidance in intrauterine insemination (IUI).

MATERIALS AND METHODS

A retrospective study was conducted. The data was collected from the records of 197 couples with unexplained infertility who underwent IUI with a total of 267 IUI cycles in the in vitro fertilization center of our hospital between January 2009 and December 2010.

RESULTS

Of the 267 IUI cycles, 145 were carried out as US-guided, while 122 cycles IUI were performed with a blind procedure. In the US-guided IUI and blinded IUI groups, the pregnancy rates were 23.4 and 13.9%, respectively. The difference between the groups was statistically significant (p = 0.049), thereby indicating that US guidance improves pregnancy rates. In the US-guided IUI group, 9.7% of the cases were difficult, while in the blinded IUI group, 26.2% were difficult and the difference between the groups was also statistically significant (p < 0.001).

CONCLUSION

US guidance in IUI improves pregnancy rates and reduces the frequency of difficult IUI.

Hyaluronan-enriched transfer medium improves outcome in patients with multiple embryo transfer failures

PURPOSE

To ascertain whether the use of hyaluronan-enriched transfer medium (HETM) improves pregnancy and implantation rates among embryo transfer patients with a history of multiple implantation failures.

METHODS

Patients (n = 314) under the age of 40 and with a history of multiple unsuccessful embryo transfers were enrolled. There were three groups of patients: those undergoing fresh embryo transfer (fresh ET [n = 111]), those undergoing vitrified-warmed ET in the natural cycle (WET-N [n = 101]) and those undergoing WET in a hormone replacement cycle (WET-H [n = 102]). On the day of ET, patients were randomized to HETM (0.5 mg/ml hyaluronan) or control medium containing no hyaluronan. Only patients with good quality embryos on day 3 were included.

RESULTS

For all three patients groups (fresh ET, WET-N and WET-H) pregnancy rates (37.5 %, 31.4 % and 41.2 %, respectively) were significantly higher when using HETM compared with control medium (10.9 %, 10.0 % and 15.7 %, respectively; p < 0.05), and implantation rates when using HETM were also significantly higher compared with control medium (p < 0.05). Miscarriage rates were similar in both groups.

CONCLUSION

HETM significantly increased pregnancy and implantation rates among embryo transfer patients with a history of multiple unsuccessful implantations-regardless of method used to prepare the endometrium.

Injection of embryo culture supernatant to the endometrial cavity does not affect outcomes in IVF/ICSI or oocyte donation cycles: a randomized clinical trial

OBJECTIVE

To evaluate whether intrauterine injection of embryo culture supernatant before embryo transfer has any impact on pregnancy and implantation rates.

STUDY DESIGN

A total of 400 cycles, of which 200 IVF/ICSI and 200 oocyte donor (OD), were randomly assigned to have their uterine cavity injected (group I) or not (group II). Primary endpoints to be studied were pregnancy and implantation rates.

RESULTS

Clinical pregnancy rate per transfer (47.87%, 90/188 versus 48.45%, 94/194) based on transvaginal scan findings at 7 weeks of gestation and implantation rate (25.6% versus 26.5%) were similar in the two groups. The day of embryo transfer, day 3 or day 5, did not affect the final outcome.

CONCLUSION

Injection of embryo culture supernatant into the uterine cavity, 30 min before the embryo transfer on either day 3 or 5, neither improves nor adversely affects the pregnancy rate in IVF/ICSI or oocyte donation cycles.

Myometrial response to neurotropic and musculotropic spasmolytic drugs in an extracorporeal perfusion model of swine uteri

To compare the effects of neurotropic and musculotropic spasmolytic drugs in isolated swine uterus specimens, 80 swine uteri were perfused using an established model for preserving a viable organ that responds to oxytocic hormones and spasmolytic drugs. An intrauterine catheter was used to record pressure changes. Following initiation of rhythmic uterine contractions and recording of spontaneous rhythmic contractions, spasmolytic drugs (butylscopolamine, atropine, denaverine, morphine, metamizole, pethidine and celandine) were administered at various concentrations. The musculotropic relaxant denaverine in particular showed significant results (P ≤ 0.05) for all dosages and parameters investigated. In terms of muscle physiology, musculotropic agents (denaverine and celandine) have clear advantages in comparison with neurotropic (butylscopolamine and atropine) or musculoneurotropic (morphine, metamizole and pethidine) spasmolytic drugs for inhibiting contractions. Experiments with pethidine (Dolantin) also showed promising results; with celandine (Paverysat), an initial increase in contractions was observed that may suggest ways of promoting rapid directed sperm transport. Denaverine and pethidine in particular may in the future be able to play an important role in improving the pregnancy rate after IVF.

Uterine Cavity Assessment Prior to IVF

Approximately 15% of couples are affected with subfertility, of which up to 20% remain unexplained. Uterine cavity abnormalities can be a contributing cause of subfertility and recurrent implantation failure. Uterine cavity assessment has been suggested as a routine investigation in the evaluation of subfertile women. Traditionally, hysterosalpingography has been the most commonly used technique in the evaluation of infertility. Transvaginal ultrasound scan allows visualization of the endometrial lining and cavity, and has been used as a screening test for the assessment of uterine cavity. Abnormal uterine findings on a baseline scan can be further evaluated with saline hysterosonography, which is highly sensitive and specific in identifying intrauterine abnormalities. Hysteroscopy is considered as the definitive diagnostic tool to evaluate any abnormality suspected on hysterosalpingography, transvaginal ultrasound scan or saline hysterosonography during routine investigation of infertile patients. Minimally invasive hysteroscopes have minimized the pain experienced by patients during the procedure and made it feasible to use hysteroscopy as a routine outpatient examination. Following recurrent IVF failure there is some evidence of benefit from hysteroscopy in increasing the chance of pregnancy in the subsequent IVF cycle, both in those with abnormal and normal hysteroscopic findings. Various possible mechanisms have been proposed for this beneficial effect, but more randomized controlled trials are needed before its routine use in the general subfertile population can be recommended.