Ultrasound-guided embryo transfer maximizes the IVF results on day 3 and day 4 embryo transfer but has no impact on day 5

Uterine factors modify the association between embryo transfer depth and clinical pregnancy

The embryo transfer depth may affect the chance of pregnancy. However, embryo dislodging caused by uterine contraction may occur after the transfer. The aim of the retrospective study was to investigate whether the factors associated with uterine contractilities, such as endometrial thickness and progesterone elevation, affect the association between transfer depth and implantation. A total of 7849 fresh transfer cycles on conventional stimulation in a single in vitro fertilization (IVF) center during the period 2013–2015 was reviewed. Patients were categorized according to quartiles of embryo transfer depth (≤ 9 mm, n = 1735, 9.1–11 mm, n = 2557, 11.1–14 mm, n = 1933, ≥ 1.4 mm, n = 1624, respectively). Adjusted for confounding factors, the adjusted odds ratio (aOR) (95% confidence interval, CI) for clinical pregnancy was 0.90 (0.79–1.02), 0.86 (0.74–0.99), and 0.70 (0.60–0.82) respectively in quartiles 2 through 4, comparing with quartile 1. However, the aORs were significantly increased when the endometrial thickness was < 8 mm. In comparison with that in the cycles with a normal endometrial thickness (8–11 mm), the aORs comparing quartiles 2 through 4 with quartile 1 in the cycles with an endometrial thickness < 8 mm increased from 0.78 (95% CI 0.65–0.93), 0.79 (95% CI 0.65–0.97), and 0.64 (95% CI 0.51–0.81) to 1.73 (95% CI 1.21–2.47), 1.04 (95% CI 0.69–1.56), and 1.45 (95% CI 0.91–2.31), respectively. In the cycles with elevated progesterone and blastocyst stage transfer, the aORs comparing quartiles 4 with quartile 1 decreased from 0.73 (95% CI 0.62–0.87) and 0.74 (95% CI 0.63–0.87) to 0.58 (95% CI 0.40–0.84) and 0.42 (95% CI 0.25–0.73) than those in the cycles without. However, only blastocyst transfer showed a significant interaction with transfer depth (p = 0.043). Our data suggested that endometrial thickness and blastocyst transfer significantly affect the association between embryo transfer depth and clinical pregnancy.

Should the flexibility enabled by performing a day-4 embryo transfer remain as a valid option in the IVF laboratory? A systematic review and network meta-analysis

PURPOSE

The present systematic review and network meta-analysis aims to uniquely bring to literature data supporting the true place of the alternative practice of day-4 embryo transfer (D4 ET) in an IVF laboratory, beyond the one-dimensional option of facilitating a highly demanding program.

METHODS

A systematic search was conducted in the databases of PubMed/Medline, Embase, and Cochrane Central Library, resulting to six prospective along with nine retrospective cohort studies meeting eligibility criteria for inclusion. A comparison of D4 ET with day-2 (D2), day-3 (D3), and day-5 (D5) ET, respectively, was performed employing R statistics.

RESULTS

The sourced results indicate no statistically significant difference regarding clinical pregnancy rates, and ongoing pregnancy/live birth rates stemming from the comparison of D4 with D2, D4 with D3, and D4 with D5 ET, respectively. Additionally, no statistically significant difference could be established in respect to cancelation, and miscarriage rates, following the comparison of D4 with D3 and D4 with D5 ET. Interestingly, we report statistically significant lower preterm birth rates associated with D4 ET, in contrast with D5 ET (RR, 0.19; 95% CI, 0.05-0.67; p value = 0.01).

CONCLUSIONS

The aforementioned results may serve as advocates buttressing the option of D4 ET as a valid candidate in the ET decision-making process. Possible limitations of the current study are the publication bias stemming from the retrospective nature of certain included studies, along with various deviations among studies' design, referring to number and quality of transferred embryos, or different culture conditions referring to studies of previous decades.

Ultrasound guidance versus the blind method for intrauterine catheter insemination: A randomized controlled trial

OBJECTIVE

The primary objective of this study was to compare clinical pregnancy rates in intrauterine insemination (IUI) treatment cycles with transabdominal ultrasound guidance during intrauterine catheter insemination (US-IUI) versus the "blind method" IUI without ultrasound guidance (BM-IUI). The secondary objective was to compare whether US-IUI had better patient tolerability and whether US-IUI made the insemination procedure easier for the clinician to perform compared to BM-IUI.

METHODS

This was a randomized controlled trial done at the Reproductive Medicine Unit of General Hospital Kuala Lumpur, Malaysia. We included women aged between 25 and 40 years who underwent an IUI treatment cycle with follicle-stimulating hormone injections for controlled ovarian stimulation.

RESULTS

A total of 130 patients were recruited for our study. The US-IUI group had 70 patients and the BM-IUI group had 60 patients. The clinical pregnancy rate was 10% in both groups (p> 0.995) and there were no significant difference between the groups for patient tolerability assessed by scores on a pain visual analog scale (p= 0.175) or level of difficulty for the clinician (p> 0.995). The multivariate analysis further showed no significant increase in the clinical pregnancy rate (adjusted odds ratio, 1.07; 95% confidence interval, 0.85-1.34; p= 0.558) in the US-IUI group compared to the BM-IUI group even after adjusting for potential covariates.

CONCLUSION

The conventional blind method for intrauterine catheter insemination is recommended for patients undergoing IUI treatment. The use of ultrasound during the insemination procedure increased the need for trained personnel to perform ultrasonography and increased the cost, but added no extra benefits for patients or clinicians.

Ultrasound versus 'clinical touch' for catheter guidance during embryo transfer in women

BACKGROUND

Many women undergoing an assisted reproductive technology (ART) cycle will not achieve a live birth. Failure at the embryo transfer stage may be due to lack of good-quality embryo/s, lack of uterine receptivity, or the transfer technique itself. Numerous methods, including the use of ultrasound guidance for proper catheter placement in the endometrial cavity, have been suggested as more effective techniques of embryo transfer. This review evaluates the efficacy of ultrasound-guided embryo transfer (UGET) compared with 'clinical touch' (CTET), which is the traditional method of embryo transfer and relies on the clinician's tactile senses to judge when the transfer catheter is in the correct position.

OBJECTIVES

To determine whether ultrasound guidance compared with clinical touch improves pregnancy outcomes in women undergoing embryo transfer during ART cycles.

SEARCH METHODS

For the 2016 update of this review, we ran updated searches in the Cochrane Gynaecology and Fertility Group trials register (May 2015), the Cochrane Central Register of Controlled Trials (the Cochrane Library, May 2015), MEDLINE (2009 to May 2015), and EMBASE (2009 to May 2015). We also handsearched relevant conference proceedings: American Society for Reproductive Medicine (ASRM), European Society for Human Reproduction and Embryology (ESHRE), and International Federation of Gynecology and Obstetrics (FIGO). There were no language restrictions.

SELECTION CRITERIA

We included only randomised controlled trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility and quality of trials and extracted data from those selected. We calculated odds ratio (OR) and 95% confidence interval (CI) for dichotomous outcomes. No outcomes were reported using continuous data. We assessed the overall quality of the evidence for the main findings using the GRADE working group methods.

MAIN RESULTS

This systematic review now has 21 included studies (four of which we added in the 2016 update), two studies awaiting assessment, and 47 excluded studies. In total, data for meta-analyses were available in 21 trials (n = 6218 women), of which only four reported live births.UGET was associated with an increased chance of a live birth/ongoing pregnancy compared with CTET (OR 1.47, 95% CI 1.30 to 1.65; 13 trials; n = 5859 women; I(2) = 74%; low-quality evidence). Sensitivity analysis by including only trials with low risk of selection bias or by using a random-effects model did not alter the effect. We estimate that for women with a chance of a live birth/ongoing pregnancy of 23% using CTET, this would increase to between 28% and 33% using UGET. We considered the quality of the evidence using GRADE methodology to be low.UGET was associated with an increase in the chance of a clinical pregnancy (OR 1.31, 95% CI 1.17 to 1.45; 20 trials; n = 6711 women; I(2) = 42%; moderate-quality evidence). We identified no differences between groups for the incidence of adverse events including multiple pregnancy, ectopic pregnancy, or miscarriage. These events were relatively rare, and sample sizes limited the ability to detect such differences.

AUTHORS' CONCLUSIONS

The evidence suggests ultrasound guidance improves the chance of live birth/ongoing and clinical pregnancies compared with clinical touch, without increasing the chance of multiple pregnancy, ectopic pregnancy, or miscarriage. Methodological limitations included: only four studies reporting details of both computerised randomisation techniques and adequate allocation concealment, only four studies reported on the outcome of live birth, and none of the nine studies that reported on ongoing pregnancy reported on live birth, suggesting possible reporting bias. Adequate reporting of randomisation and allocation concealment will improve the quality of future studies. The primary outcome measure of future studies should be the reporting of live births per woman randomised.

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.

Ultrasound versus 'clinical touch' for catheter guidance during embryo transfer in women

BACKGROUND

Many women undergoing an Assisted Reproductive Technology (ART) cycle will not achieve a live birth. Failure at the embryo transfer stage may be due to lack of good quality embryo/s, lack of uterine receptivity, or the transfer technique itself. Numerous methods, including the use of ultrasound guidance for proper catheter placement in the endometrial cavity, have been suggested as a more effective technique of embryo transfer. This review evaluates the effectiveness of ultrasound guided embryo transfer (UGET) compared with 'clinical touch' (CTET) the traditional method of embryo transfer.

OBJECTIVES

To determine whether ultrasound guidance influences treatment outcomes in women undergoing embryo transfer (ET) during assisted reproductive technology (ART) cycles.

SEARCH STRATEGY

Electronic databases were searched in November 2009. We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched November 2009), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2009), MEDLINE (1970-2009), EMBASE (1985-2009), BIO Extracts (1980-2009). Relevant conference proceedings were also hand searched (ASRM, ESHRE and FIGO).

SELECTION CRITERIA

Only randomised controlled trials were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed eligibility and quality of trials and extracted data from those selected.

MAIN RESULTS

This update identified 59 potential trials of which 42 were excluded. Data for analysis was available in seventeen studies. One study reported live births and personal communication resulted in data relating to this outcome being obtained in two additional studies. There is no evidence of a significant difference in the outcome of live birth (OR 1.14 (95%CI0.93 to 1.39; P=0.02) although heterogeneity was high (64%) and the results should be interpreted with caution. Seven studies reported on ongoing pregnancies. The ongoing pregnancies per woman randomised associated with UGET (441/1254) was significantly higher than for clinical touch (350/1218) OR 1.38, 95%CI 1.16 to 1.64, P<0.0003). No statistically significant differences in the incidence of adverse events were identified between the comparison groups. These events are relatively rare and sample sizes limit the ability to detect such differences.

AUTHORS' CONCLUSIONS

The studies are limited by their quality with only two studies reporting details of both computerised randomisation techniques and adequate allocation concealment. Ultrasound guidance does appear to improve the chances of live/ongoing and clinical pregnancies compared with clinical touch methods. The quality of future studies should be improved with adequate reporting of randomisation, allocation concealment, and power calculations. The primary outcome measure of future studies should be the reporting of live births per woman randomised.

The position of transferred air bubbles after embryo transfer is related to pregnancy rate

OBJECTIVE

The possibility to visualize the transfer air bubbles is one of the main benefits of ultrasonographic-guided embryo transfer. The objective of this study was to analyze the relation between the position of the air bubbles and pregnancy rates.

DESIGN

Prospective data-analysis.

SETTING

University fertility clinic.

PATIENT(S)

IVF and intracytoplasmic sperm injection patients.

INTERVENTION(S)

Transabdominal ultrasonographic guidance at embryo transfer.

MAIN OUTCOME MEASURE(S)

Pregnancy rate, length endometrial plate, distance catheter to fundus, distance air bubbles to fundus.

RESULT(S)

Analysis of 367 consecutive ultrasonographic-guided embryo transfers following IVF or intracytoplasmic sperm injection treatment. Both absolute and relative position of the air bubbles were significantly closer to the fundus in patients who became pregnant compared with patients who did not become pregnant. When the relative position of the air bubbles was in the fundal half of the endometrial plate pregnancy rates were significantly higher compared with the lower half of the endometrial plate, 43.0% and 24.4%, respectively, P=.002. Multiple regression analysis revealed the relative position as an independently associated determinant for pregnancy.

CONCLUSION(S)

The position of the air bubbles after embryo transfer is related to pregnancy rate; the highest pregnancy rates are found when the air bubbles end up closer to the fundus.

The impact of the depth of embryo replacement on IVF outcome

PURPOSE

To evaluate the effect of the depth of embryo transfer replacement on clinical pregnancy rate.

METHODS

Data from a total of 104 consecutive embryo transfers performed on 104 women aged 26-37 years were prospectively collected for this study. All patients underwent a standard down regulation protocol for ovarian stimulation. Oocytes retrieval were performed at 36 h after hCG administration. Embryo transfer took place at 48 h after insemination. The patients were matched in two groups according to the distance between the tip of the catheter and the uterine fundus at transfer (group A > 10 < 15 mm and group B < or = 10 mm). The same method of loading embryos into the embryo transfer catheter was used.

RESULTS

Clinical pregnancy rates varied significantly (p < or = 0.05) between the two groups: 27.7% in group A and 14% in group B. The number and quality of embryos transferred did not differ between the groups.

CONCLUSIONS

The results suggest that the depth of embryo replacement may be an important variable in embryo transfer technique.

Ultrasound-guided embryo transfer does not offer any benefit in clinical outcome: a randomized controlled trial

BACKGROUND

Ultrasound-guided embryo transfer (ET) is widely suggested as a standard clinical practice that improves overall embryo implantation and pregnancy rates. Various studies of this issue suffer from methodological pitfalls, so that a randomized controlled trial, which overcomes these problems, might be valuable.

METHODS

Three hundred women aged <40, who underwent fresh ET, were included in this randomized, double-blind controlled trial. The K-J-SPPE echo tip soft catheter was used for the ultrasound-guided ET and the traditional K-Soft catheter for ETs not using ultrasound. One experienced operator performed all ETs. The primary study outcome was overall pregnancy rate (defined as the number of positive hCG results per transfer).

RESULTS

No significant differences between groups were found regarding baseline patient and embryological characteristics, except for male factor and unexplained infertility (higher in the blind and ultrasound-guided ET group, respectively, P < 0.05). Overall pregnancy rates were 53.3 and 51.3% in the ultrasound-guided and blind ET group, respectively. Two ectopic pregnancies were reported in each group. Difficulty in cervical negotiation did not differ between the two groups.

CONCLUSIONS

In patients undergoing ET by an experienced operator, ultrasound guidance did not provide any benefit in terms of overall clinical pregnancy and embryo implantation rates.

Ultrasound versus 'clinical touch' for catheter guidance during embryo transfer in women

BACKGROUND

Many women undergoing an Assisted Reproductive Technology (ART) cycle will not achieve a live birth. Failure at the embryo transfer stage may be due to poor embryo quality, lack of uterine receptivity, or the transfer technique itself. Numerous methods, including the use of ultrasound guidance for proper catheter placement in the endometrial cavity, have been suggested as a means of improving the technique of embryo transfer. This review evaluates the effectiveness of ultrasound (UGET) in comparison with 'clinical touch' embryo transfer (CTET) the traditional method of embryo transfer.

OBJECTIVES

:To determine whether ultrasound guidance influences treatment outcomes in women undergoing embryo transfer (ET) during assisted reproductive technology (ART) cycles.

SEARCH STRATEGY

All electronic databases were searched on 20 th August 2006. We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched August 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2006), MEDLINE (1970-2006), EMBASE (1985-2006), BIO Extracts (1980-2006). Relevant conference proceedings were also hand searched (ASRM, ESHRE and FIGO).

SELECTION CRITERIA

Only randomised controlled trials were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed eligibility and quality of trials and extracted data from those selected.

MAIN RESULTS

Thirteen out of fifteen identified studies were eligible for analysis. No study reported live births, however, personal communication resulted in data relating to this outcome being obtained in two of the studies. Six studies reported on ongoing pregnancies. The live birth/ ongoing pregnancies per woman randomised associated with UGET (452/1376) was significantly higher than for clinical touch (353/1338) OR 1.40, 95%CI 1.18 to 1.66, P<0.0001). This means, for example, that for a population of women with a 25% chance of pregnancy using clinical touch this would be increased to 32% (28% to 46%) by using UGET. There were no statistically significant differences in the incidence of adverse events between the two comparison groups with the exception of blood on the catheter.

AUTHORS' CONCLUSIONS

The studies are limited by their quality with only one of the thirteen studies reporting details of both computerised randomisation techniques and adequate allocation concealment. Ultrasound guidance does appear to improve the chances of live/ongoing and clinical pregnancies compared with clinical touch methods. The quality of future studies should be improved with adequate reporting of randomisation, allocation concealment, and power calculations. The primary outcome measure of future studies should be the reporting of live births per woman randomised.

Is what we clearly see really so obvious? Ultrasonography and transcervical embryo transfer—a review

OBJECTIVE

To critically review the role of ultrasound-guided embryo transfer (ET) and its influence on the outcome of in vitro fertilization (IVF).

DESIGN

Medline review of published manuscripts.

RESULT(S)

Studies evaluating the role of ultrasound-assisted ET have had mixed results, and although meta-analysis of prospective trials suggests an improvement in outcome, limitations in study design may overstate the effect of ultrasonography. Other ET techniques may eliminate the advantages provided by ultrasonography, limiting its benefit to specific clinical scenarios. However, because no trial has demonstrated an adverse effect and because cases that may benefit from its use often cannot be predicted reliably, the routine application of ultrasonography can be justified.

Ultrasonographic-guided embryo transfer does not enhance pregnancy rates compared with embryo transfer based on previous uterine length measurement

OBJECTIVE

To compare pregnancy rates (PRs) after ultrasound-guided embryo transfer and embryo transfer based on ultrasonographic length measurement.

DESIGN

Prospective intervention group combined with retrospective control group.

SETTING

University fertility clinic.

PATIENT(S)

Patients undergoing IVF and intracytoplasmic sperm injection.

INTERVENTION(S)

Transabdominal ultrasonographic guidance at embryo transfer.

MAIN OUTCOME MEASURE(S)

Pregnancy and implantation rates.

RESULT(S)

In 367 ultrasound-guided embryo transfers clinical PR, ongoing PR, and implantation rate were 35.1%, 31.1%, and 24.3%, respectively. In 363 embryo transfers based on previous ultrasonographic length measurement, the rates were 33.9%, 29.5%, and 24.2%, respectively. There were no statistical significant differences between the groups.

CONCLUSION(S)

Ultrasonographic guidance does not show any benefit in terms of PR and implantation rate compared to previous ultrasonographic length measurement, an other precise and atraumatic transfer technique.

Transabdominal ultrasound–assisted embryo transfer and pregnancy outcome

OBJECTIVE

To assess the clinical value of transabdominal ultrasound (TAS)--assisted embryo transfer on outcomes of in vitro fertilization--embryo transfer (IVF-ET) in comparison to the "clinical touch" method of transcervical embryo transfer by one physician and to determine if transabdominal ultrasound should be applied to all cases of embryo transfer in this practice.

DESIGN

A retrospective comparison study.

SETTING

A university-based IVF practice.

PATIENT(S)

Two hundred forty-nine patients who underwent transcervical transfer of fresh embryos created using autologous oocytes performed by the same physician from July 1, 2003, to June 30, 2004.

INTERVENTION(S)

On selected days, at time of embryo transfer, transabdominal ultrasound was performed to guide catheter placement depth approximately 1 cm from the uterine fundus.

MAIN OUTCOME MEASURE(S)

The presence of at least one gestational sac on ultrasound was compared in the two study groups; additionally, the clinical pregnancy rate (presence of fetal cardiac activity observed on ultrasound), the ectopic pregnancy rate, the biochemical pregnancy rate, and the implantation rate (number of gestational sacs identified on ultrasound per number of embryos transferred) between groups was evaluated. Characteristics of the two cohorts were analyzed to verify similarities between the treatment and control groups, including age of recipient, prior IVF history, day of transfer (day 3 or day 5 after retrieval), difficulty of transfer, the use of a tenaculum, and the quality and number of embryos transferred.

RESULT(S)

No statistical difference was seen in the presence or number of gestational sacs following embryo transfer with or without transabdominal ultrasound guidance.

CONCLUSION(S)

No additional advantage is conferred when using transabdominal ultrasound to perform embryo transfer. In experienced hands, the "clinical touch" method of embryo transfer yields equivalent results to transabdominal ultrasound-guided embryo placement. However, in patients with a prior history of difficult uterine sounding or embryo transfer, transabdominal ultrasound guidance may still play a role.

Ultrasound-guided trial transfer may be beneficial in preparation for an IVF cycle

BACKGROUND

The objective of this study is to determine if ultrasound-guided trial transfer (UTT) in the office in preparation for an IVF cycle can be utilized as an alternative and/or adjunct to ultrasound-guided embryo transfer (UGET).

METHODS

Patients planning to undergo an IVF cycle at an academic centre were included. Each patient underwent an UTT in the office by the same practitioner. The difference in length (DL), if any, was measured from the perceived top of the uterine cavity (catheter tip) to the actual cavity apex as visualized by ultrasound.

RESULTS

Of the 64 patients enrolled, 19 patients (29.7%) had a measurable DL, of which 14 (21.9%) had a DL exists 0.5 cm, and nine (14.1%) had a DL exists 1.0 cm. Significant differences were noted between patients when comparing DL to previous pregnancy status and the total cavity depth (sounding depth + DL) (P < 0.05).

CONCLUSION

UTT in the office setting appears to be beneficial in preparation for an IVF cycle with embryo transfer.

GnRH agonist versus GnRH antagonist in oocyte donation cycles: a prospective randomized study

BACKGROUND

The specific role of LH in folliculogenesis and oocyte maturation is unclear. GnRH antagonists, when administered in the late follicular phase, induce a sharp decrease in serum LH which may be detrimental for IVF outcome. This study was performed to evaluate whether the replacement of GnRH agonist (triptorelin) by a GnRH antagonist (ganirelix; NV Organon) in oocyte donation cycles has any impact on pregnancy and implantation rates.

METHODS

A total of 148 donor IVF cycles was randomly assigned to use either a GnRH antagonist daily administered from the 8th day of stimulation (group I) or a GnRH agonist long protocol (group II) for the ovarian stimulation of their donors. The primary endpoints were the pregnancy and the implantation rates.

RESULTS

The clinical pregnancy rate per transfer (39.72%, 29/73 versus 41.33%, 31/75) based on transvaginal scan findings at 7 weeks of gestation, the implantation rate (23.9 versus 25.4%) and the first trimester abortion rate (10.34 versus 12.90%) were similar in the two groups.

CONCLUSION

In oocyte donation cycles the replacement of GnRH agonist by a GnRH antagonist appears to have no impact on the pregnancy and implantation rates when its administration starts on day 8 of stimulation.

Embryo afterloading: a refinement in embryo transfer technique that may increase clinical pregnancy

OBJECTIVE

Given the importance of ET technique during assisted reproductive technology cycles, we evaluated the effect of embryo afterloading subsequent to placement of the ET catheter on pregnancy rates vs. a standard direct ET.

DESIGN

Retrospective cohort analysis.

SETTING

University-based assisted reproductive technology program.

PATIENT(S)

Patients undergoing a fresh nondonor day 3 ET by a single provider over a 1-year period.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy.

RESULT(S)

One hundred twenty-seven patients met inclusion criteria, and the overall pregnancy rate was 46.5%. There was no difference between the two groups with respect to age, basal FSH, or number of embryos transferred. The ET method used was at the discretion of the provider. There was no difference between the two groups in the presence of blood on the transfer catheter. However, there were significantly more transfer catheters with mucus contamination in the direct transfer group (25.58% vs. 5.95%). The clinical pregnancy rate in the group with ET using the afterloading technique was higher than in the direct ET group (52.4% vs. 34.9%).

CONCLUSION(S)

There was a trend toward an increase in pregnancy rate when an embryo afterloading technique was used. A prospective randomized trial is needed to examine this issue.

Ultrasound-guided embryo transfer and the accuracy of trial embryo transfer

BACKGROUND

Studies have suggested that ultrasound-guided embryo transfer (UG-ET) may improve the outcome in IVF; however, several factors may account for the improvement in pregnancy rate. This study examines the use of ultrasound to determine the accuracy of trial transfer (TT) in preparation for ET.

METHODS

Sixty-seven consecutive patients prospectively underwent UG-ET over a 2 month period. Total cavity length by US was compared with the length noted by TT. A difference of > or = 1 cm was considered significant. All embryos were placed within 1-2 cm of the fundus by US.

RESULTS

Twenty patients (29.9%) had a difference of > or = 1 cm and 13 patients (19.4%) had a difference of < or = 1.5 cm. Patients with a difference of > or = 1 or > or = 1.5 cm had a significantly greater depth at transfer (P < 0.001) and uterine cavity length (P < 0.001) when compared with patients without a difference. Clinical pregnancy, implantation, delivery and overall miscarriage rates did not differ between patients with a difference of > or = 1 or > or = 1.5 cm versus no difference. There were no ectopic pregnancies.

CONCLUSIONS

Nineteen percent of patients had a discrepancy of > or = 1.5 cm and approximately 30% had a difference of > or = 1 cm from TT at UG-ET, suggesting a benefit to UG-ET. A large prospective randomized trial comparing UG-ET with blind transfer is required to assess further if UG-ET should be used in all cases of ET.

Implantation Failure in Assisted Reproduction Technology and a Critical Approach to Treatment

In this article, we review the literature and our personal experience regarding the many factors that appear to influence implantation rate. Oocyte quality, as determined by patient age and aneuploidies, probably plays a major role in RIF. However, a panoply of other factors have been brought under investigation, quite often with contradictory results and additional intriguing questions to be studied. Infections of the vagina, cervix, and endometrium, the role of mucus aspiration and washing of the cervix on transfer, the role of catheter guidance for a correct transfer and potion of embryos, the effect of mock transfer, and the role of hysteroscopy and its timing before transfer procedures are analyzed both as a review of the literature and as opinions and data from our experience. Many of these factors are interlaced and from the apparently simple issue of trauma, to infections and immune modulation of hatching and implantation, a biological continuum can easily be identified. The impact of abnormalities of the immune system and of homeostasis abnormalities is also covered in a brief overview of reported works and our experience. These latter areas probably constitute the common biological background of all other external factors that, however, the skilled must equip themselves for improving implantation success.

The Impact of Embryo Transfer on Implantation—A Review

Embryo transfer has received little clinical attention and has been, until recently, the most inefficient step in in-vitro fertilization (IVF). In this article, the authors review the literature and their personal experience regarding the process of intrauterine transfer of embryos, which remains the object of much discussion. Factors which appear to influence implantation rates are: contamination of the catheter tip with cervical bacteria, stimulation of uterine contractions during the procedure, the type of catheter, ultrasound guidance during the transfer, and the position of the embryos in the uterine cavity. Easy and atraumatic transfer is essential for successful implantation and the embryos need to be placed in the middle of the cavity, away from the fundus. Knowing, beforehand, the position and length of the uterus can provide better results and may reduce the rate of ectopic pregnancies. Evidence from randomized studies has supported this claim. Despite the number of available studies controlling certain variables, most authors, even using the same catheter, ultrasound guidance and/or a trial transfer use different protocols or similar instruments in different ways. Standardization of the transcervical intrauterine transfer of embryos in a large randomized study is needed before definitive conclusions can be drawn. The goal of improved implantation and pregnancy rates deserve these efforts.

Ultrasound-guided embryo transfer: a meta-analysis of randomized controlled trials

OBJECTIVE

To conduct a meta-analysis of randomized controlled studies to evaluate abdominal ultrasound-guided embryo transfer compared to the clinical touch method.

DESIGN

Meta-analysis.

SETTING

Four studies performed in academic research centers in Barcelona, Vizcaya, Hong Kong, and Madrid.

PATIENT(S)

A total of 2,051 patients: 1,024 received ultrasound-guided embryo transfers and 1,027 received clinical touch method transfers.

INTERVENTION(S)

Fourteen studies were retrieved from the literature, but only four of them fitted our selection criteria. The meta-analysis was conducted using the RevMan software with the Peto-modified Mantel-Haenszel method and the fixed effect model.

MAIN OUTCOME MEASURE(S)

The primary outcome measures were the clinical pregnancy and ongoing pregnancy rates. The secondary outcome measures were the incidences of ectopic pregnancies, miscarriage rate, multiple pregnancies, and difficult transfers.

RESULT(S)

Compared to the clinical touch method, abdominal ultrasound-guided transfer significantly increased the clinical pregnancy rate and the ongoing pregnancy rate. There was no effect on the incidence of ectopic pregnancy, multiple pregnancy, or miscarriage rate. CONCLSUION(S): Ultrasound-guided embryo transfer increases the clinical pregnancy and ongoing pregnancy rates significantly compared to the clinical touch method.

A meta-analysis of ultrasound-guided versus clinical touch embryo transfer

OBJECTIVE

To determine the relative efficacy of ultrasound-guided embryo transfer and embryo transfer by clinical touch alone.

DESIGN

Systematic review and meta-analysis of randomized, controlled trials comparing ultrasound-guided embryo transfer with embryo transfer by clinical touch alone.

SETTING

Infertility centers providing treatment with in vitro fertilization/embryo transfer.

PATIENT(S)

Women undergoing embryo transfer.

INTERVENTION(S)

Embryo transfer with or without transabdominal ultrasound guidance.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate and embryo implantation rate.

RESULT(S)

A total of eight prospective controlled trials were identified. Of these studies, four were nonrandomized or quasi-randomized and four were genuinely randomized. Meta-analysis demonstrated a significantly increased chance of clinical pregnancy following ultrasound-guided embryo transfer in all studies and in the genuinely randomized subgroup. The embryo implantation rate was also significantly increased following ultrasound-guided embryo transfer.

CONCLUSION(S)

Ultrasound-guided embryo transfer significantly increases the chance of clinical pregnancy and significantly increases the embryo implantation rate.

Impact of transabdominal ultrasound guidance on performance and outcome of transcervical uterine embryo transfer

PURPOSE

To determine the impact of transabdominal ultrasound guidance on embryo transfer during IVF therapy.

METHODS

Retrospective analysis of 823 consecutive embryo transfers. Three hundred and sixty-seven procedures performed with transabdominal ultrasound guidance were compared to 456 cases performed with the "clinical touch" method.

RESULTS

Ultrasound-guided embryo transfer yielded higher, but not statistically significant, clinical pregnancy (48% vs. 44%) and implantation rates (22% vs. 20%). The incidence of multiple pregnancies, ectopic and multiple pregnancy rates were similar. The frequency of negative factors typically associated with difficult transfers, such as requirement of use of tenaculum, and presence of blood or mucus in the catheter tip, were significantly lower in the ultrasound-guided group in comparison with the clinical touch group. Ultrasound-guided embryo transfer was associated with a significantly increased easiness of transfer performance; 95% of the transfers were rated as very easy in the ultrasound-guidance group compared to 87% in the clinical touch group. The use of a soft pass catheter was the only variable independently and significantly associated with pregnancy success (odds ratio = 2.74).

CONCLUSION(S)

Ultrasound-guidance facilitates embryo transfer and in combination with the use of a soft catheter should be implemented to optimize embryo transfer results.

The transfer point is a novel measure of embryo placement

OBJECTIVE

To study the relationship between IVF-ET pregnancy outcomes and measures of embryo placement.

DESIGN

Case-control study.

SETTING

Tertiary care center.

PATIENT(S)

Twenty-three patients who underwent two ultrasonography-guided ETs, of which one resulted in a clinical pregnancy and the other did not.

MAIN OUTCOME MEASURES

Point of embryo placement normalized to the endometrial cavity length (the transfer point), distance from the point of embryo placement to the uterine fundus, time required for ET, contact with the uterine fundus, and evidence of trauma. Videotaped ETs were quantitatively analyzed.

RESULT(S)

From February 1, 2000, to March 31, 2001, videotaped ETs from 23 pairs of pregnant and nonpregnant cycles were identified. Embryo placement was more shallow in pregnancy cycles than in nonpregnancy cycles. The groups did not differ in the absolute distance of embryo placement to the fundus, ovarian stimulation, or other features of the ET.

CONCLUSION(S)

The transfer point may serve as a better marker of embryo position than does the absolute distance to the uterine fundus.

Embryo transfer: hysteroscopic assessment of transfer catheter effects on the endometrium

So far as is known, this is the first series to report the effects of embryo transfers on endometrial integrity as assessed by direct hysteroscopic visualization. Subjects (n = 30) were patients of reproductive age undergoing diagnostic hysteroscopy. A mock embryo transfer was performed by a single clinician, immediately followed by saline hysteroscopy using a 2.7 mm hysteroscope. Hegar dilators or uterine sounds were not used. Representative video clips were recorded for independent assessment of endometrial integrity. (The movie sequence may be purchased for viewing on the internet at www.rbmonline.com/Article/1040; it is free to web subscribers.) Outcomes measured were ease of transfer (easy, moderate, difficult, very difficult) and details of the transfer technique. Endometrial damage was independently assessed and graded as follows: none, minor, moderate or severe. Of the easy transfers, 54% showed no endometrial damage. However, there 37% showed moderate to severe damage in the easy transfer group. Of the moderately difficult transfers, there was no clear association between perceived difficulty of transfer and amount of endometrial damage. Clinical perception of ease of transfer does not correlate well with the degree of endometrial disruption (P = 0.41). Use of hysteroscopy offers a unique insight into the effects of embryo transfer on endometrial integrity.

Transabdominal ultrasound-guided embryo transfer does not increase pregnancy rates in oocyte recipients

OBJECTIVE

To determine whether transabdominal ultrasound guidance during embryo transfer (ET) is a useful tool for increasing pregnancy rates in patients undergoing oocyte donation.

DESIGN

Prospective, randomized, controlled trial.

SETTING

In vitro fertilization academic center.

PATIENT(S)

Three hundred seventy-four infertile patients undergoing oocyte donation.

INTERVENTION(S)

Transabdominal ultrasound-guided ET.

MAIN OUTCOME MEASURE(S)

We measured the pregnancy rate and implantation rate after transabdominal ultrasound-guided ET versus the rates in a control group who did not receive transabdominal ultrasound-guided ET.

RESULT(S)

Clear visualization at ultrasound during ET was achieved in 90.8% of the patients who had ultrasound-guided ET. A similar number of easy transfers were performed in both the ultrasound-guided and the control groups (84.5% vs. 86.6%). The pregnancy rate was comparable between the groups (59.9% ultrasound vs. 55.1% control), as was the implantation rate (30.6% ultrasound vs. 26.3% control). No differences were found in the miscarriage rate (10.7% ultrasound vs. 9.1% control) or in the multiple pregnancy rate (21.4% ultrasound vs. 22.5% control). Although all ectopic pregnancies occurred in the group that did not receive ultrasound guidance, the differences were not statistically significant (0 vs. 2.7%).

CONCLUSION(S)

We could not show any benefit in terms of pregnancy rate in oocyte recipients for whom ET was performed under direct transabdominal ultrasound visualization of the endometrial cavity. There was a lower ectopic pregnancy rate when ultrasound guidance was used, but this rate was not statistically significant in comparison with the pregnancy rate without ultrasound guidance.

Ultrasound-guided embryo transfer improves pregnancy rates and increases the frequency of easy transfers

BACKGROUND

Recent reports have suggested that ultrasound (US) guidance during embryo transfer might improve pregnancy rates.

METHODS

A prospective randomized (computer-generated random table) trial was performed to compare embryo transfer under abdominal US guidance (n = 255 women) with clinical touch embryo transfer (n = 260).

RESULTS

The clinical pregnancy rate was 26.3% (67/255) in the US-guided transfer group compared with 18.1% (47/260) in the clinical touch transfer group (P < 0.05). The implantation rate was 11.1% (100/903) in the US group compared with 7.5% (66/884) in the clinical touch group (P < 0.05). US-guided transfer was associated with a decrease in the difficulty of the transfers: 97% of transfers were easy in the US-guided group compared with 81% in the clinical touch group (P < 0.05).

CONCLUSIONS

US-guided embryo transfer increased pregnancy and implantation rates in IVF cycles, as well as the frequency of easy transfers. It is suggested that the decrease in cervical and uterine trauma can play a role in the increase in pregnancy rates associated with US-guided transfer. It is recommended that embryo transfer should be performed under US guidance.

Ultrasound measurement of the uterocervical angle before embryo transfer: a prospective controlled study

BACKGROUND

The study aim was to determine whether moulding the embryo transfer catheter according to the uterocervical angle measured by ultrasound could improve pregnancy and implantation rates.

METHODS

Patients were alternately allocated to one of two groups. In the ultrasound-guided group (n = 320), the catheter was moulded according to the uterocervical angle measured by abdominal ultrasound. In controls (n = 320), embryo transfer was performed using the "clinical feel" method.

RESULTS

Moulding the embryo transfer catheter according to the uterocervical angle significantly increased clinical pregnancy [(OR = 1.57, 95% CI (1.08-2.27)] and implantation rates [(OR = 1.47, 95% CI (1.10-1.96)] compared with the "clinical feel" method. It also significantly reduced difficult transfers [(OR = 0.25, 95% CI (0.16-0.40)] and blood during transfers [OR = 0.71, 95% CI (0.50-0.99)]. Patients with large angles (>60 degrees ) had significantly lower pregnancy rates compared with those with no angle [OR = 0.36, 95% CI (0.16-0.52)].

CONCLUSIONS

Moulding the embryo transfer catheter according to the uterocervical angle measured by ultrasound increases clinical pregnancy and implantation rates and diminishes the incidence of difficult and bloody transfers.