Ultrasound-guided embryo transfer: summary of the evidence and new perspectives. A systematic review and meta-analysis

Sonographer-guided frozen embryo transfer vs ultrasound-assisted frozen embryo transfer - A randomised controlled study

BACKGROUND

The use of ultrasound to guide placement of the embryo during in vitro fertilisation (IVF) is important, but there are times where a good image cannot be obtained. Having a trained sonographer perform the ultrasound may therefore improve the success of embryo transfer.

AIM

To determine whether the routine use of a sonographer to guide embryo transfer is superior to standard care.

MATERIALS AND METHODS

Randomised, controlled, prospective clinical study in a private infertility clinic. There were 113 women aged <38 years undergoing frozen embryo transfer (donor egg/embryo excluded) who were randomised to sonographer-guided embryo transfer or standard care (the doctor performs an ultrasound prior to embryo transfer and the patient holds the ultrasound probe). The primary outcome was visualisation of the air bubble, and secondary outcomes were distance of the air bubble from the fundal endometrium, pregnancy rate (gestational sac on ultrasound at seven weeks) and live birth rate.

RESULTS

The bubble was visualised in 100% of embryo transfers with a sonographer compared to 83% in the ultrasound-assisted group, and this was statistically significant (P < 0.01). No statistically significant differences were found in terms of distance from the fundal endometrium or in pregnancy rate and live birth rate.

CONCLUSION

Sonographer-guided embryo transfer leads to statistically higher rates of visualisation of the air bubble compared to ultrasound-assisted transfer.

Uterine cervical stenosis: from classification to advances in management. Overcoming the obstacles to access the uterine cavity

BACKGROUND

To date hysteroscopy is the gold standard technique for the evaluation and management of intrauterine pathologies. The cervical canal represents the access route to the uterine cavity. The presence of cervical stenosis often makes entry into the uterine cavity difficult and occasionally impossible. Cervical stenosis has a multifactorial etiology. It is the result of adhesion processes that can lead to the narrowing or total obliteration of the cervical canal.

PURPOSE

In this review, we summarize the scientific evidence about cervical stenosis, aiming to identify the best strategy to overcome this challenging condition.

METHODS

The literature review followed the scale for the quality assessment of narrative review articles (SANRA). All articles describing the hysteroscopic management of cervical stenosis were considered eligible. Only original papers that reported data on the topic were included.

RESULTS

Various strategies have been proposed to address cervical stenosis, including surgical and non-surgical methods. Medical treatments such as the preprocedural use of cervical-ripening agents or osmotic dilators have been explored. Surgical options include the use of cervical dilators and hysteroscopic treatments.

CONCLUSIONS

Cervical stenosis can present challenges in achieving successful intrauterine procedures. Operative hysteroscopy has been shown to have the highest success rate, particularly in cases of severe cervical stenosis, and is currently considered the gold standard for managing this condition. Despite the availability of miniaturized instruments that have made the management of cervical stenosis more feasible, it remains a complex task, even for experienced hysteroscopists.

First case of dichorionic diamniotic triplet pregnancy after single blastocyst transfer

Multiple pregnancies are associated with significant maternal, fetal, and neonatal risks, including prematurity, low birth weight, pre-eclampsia, anemia, postpartum hemorrhage, intrauterine growth restriction, neonatal morbidity, and increased neonatal and infant mortality rates. Assisted reproductive technology (ART) treatments should prioritize efforts to reduce such events, resisting patient demand for the transfer of multiple embryos at each transfer to increase success rates. Extended culture, embryo selection, and single blastocyst transfer can mitigate the risk of high-order multiple pregnancies. Intriguingly, elective single-embryo transfer (eSET) greatly reduces, but does not completely eliminate, the likelihood of multiple gestations. The occurrence of monozygotic twinning (MZT) gives rise to identical twins. It is more prevalent in women undergoing in vitro fertilization (IVF) compared with natural conception. In fact, the reported risks of monozygotic twinning in IVF and natural conception are 1.7 and 0.4%, respectively. The factors suspected to increase the risk of MZT in IVF are multiple embryo transfer, micromanipulation, and extended in vitro culture. Determining chorionicity and amnionicity is crucial in the assessment of multiple pregnancies during the first-trimester ultrasound examination. Dichorionic twins result from embryo splitting within 3 days after fertilization, while monochorionic twins occur when the splitting takes place between 4 and 8 days after fertilization. These timings are suggested by observations carried out in natural pregnancies. In ART, there is evidence of dichorionic twins derived from single embryo transfer (SET). Here, we report a case of dichorionic diamniotic triplets after a single blastocyst transfer occurred in our center. To our knowledge, this is the first case documented so far.

Isthmocele, not cesarean section per se, reduces in vitro fertilization success: a systematic review and meta-analysis of over 10,000 embryo transfer cycles

IMPORTANCE

Previous reviews have shown that a history of cesarean section (CS) is associated with a worse in vitro fertilization (IVF) prognosis. To date, whether the decline in the IVF chances of success should be attributed to the CS procedure itself or to the presence of isthmocele remains to be clarified.

OBJECTIVE

To summarize the available evidence regarding the impact of isthmocele on IVF outcomes.

DATA SOURCES

Electronic databases and clinical registers were searched until May 30, 2023.

STUDY SELECTION AND SYNTHESIS

Observational studies were included if they assessed the effect of isthmocele on IVF outcomes. Comparators were women with isthmocele and women without isthmocele with a previous CS or vaginal delivery. Study quality was assessed using the modified Newcastle-Ottawa Scale.

MAIN OUTCOMES

The primary outcome was the live birth rate (LBR). The effect measures were expressed as adjusted odds ratios (aORs) and unadjusted odds ratios (uORs) with 95% confidence intervals (95% CIs). The body of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation working group methodology.

RESULTS

Eight studies (n = 10,873 patients) were included in the analysis. Women with isthmocele showed a lower LBR than both women with a previous CS without isthmocele (aOR, 0.62; 95% CI, 0.53-0.72) and those with a history of vaginal delivery (aOR, 0.55; 95% CI, 0.42-0.71). The LBRs in women with a previous CS without isthmocele and those with a history of vaginal delivery were similar (aOR, 0.74; 95% CI, 0.47-1.15). Subgroup analysis suggested a negative effect of the intracavitary fluid (ICF) in women with isthmocele on the LBR (uOR, 0.36; 95% CI, 0.18-0.75), whereas the LBRs in women without ICF and those without isthmocele were similar (uOR, 0.94; 95% CI, 0.61-1.45).

CONCLUSION AND RELEVANCE

We found moderate quality of evidence (Grading of Recommendations Assessment, Development and Evaluation grade 3/4) supporting a negative impact of isthmocele, but not of CS per se, on the LBR in women undergoing IVF. The adverse effect of isthmocele on IVF outcomes appears to be worsened by ICF accumulation before embryo transfer.

CLINICAL TRIAL REGISTRATION NUMBER

CRD42023418266.

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.

A delayed spontaneous second-trimester tubo-abdominal pregnancy diagnosed and managed by laparotomy in a "self-identified" infertile woman, a case report and literature review

BACKGROUND

Abdominal pregnancy, a rare form of ectopic pregnancy, is associated with high morbidity and adverse consequences for future fertility. Early recognition and management reduce mortality and allow minimal invasive and conservative treatment. In modern medicine, primitive prevention to unexpected fatal pregnancies is crucial.

CASE PRESENTATION

A divorced 33-year-old "self-identified" infertile polycystic ovary woman diagnosed as repeated implantation failure in previous in vitro fertilization with her ex-husband ever presented in surgery department with a history of 15-day abdominal pain, nausea, and vomiting and 3-h worsening abdominal pain. The serum beta-human chorionic gonadotropin value was more than 10,000 m-international units per milliliter. Sonogram findings were significant for the absence of intrauterine gestation; a placenta and well-formed living fetus of second-trimester gestation were seen in the abdomen, accompanied by hemoperitoneum. A unique spontaneously second-trimester tubo-abdominal pregnancy was confirmed in emergent laparotomy by gynecologists, she received a removing of the living fetus, a right total salpingectomy, resection of partial omentum and blood transfusion. The patient recovered uneventfully and her serum beta-human chorionic gonadotropin returned to normal range on the 30th postoperative day, till now, she has weak fertility awareness because of her catastrophic experiences in the unexpected abdominal pregnancy.

CONCLUSIONS

This case highlights woman with a previous in vitro fertilization history may be in is a high risk to be delayed or missed in diagnosis in an intended ectopic pregnancy due to a fixed belief in infertility. Educational interventions and contraceptive care should be provided by fertility and healthcare practitioner. The possibility of abdominal pregnancy must always be suspected and dealt with promptly and appropriately by the astute clinician.

The effect of the day 3 embryo cell number on the neonatal outcomes of day 5 single blastocyst transfer in frozen embryo transfer cycles

OBJECTIVE

To evaluate the influence of the day 3 embryo cell number on the neonatal outcomes of day 5 single blastocyst transfer in frozen embryo transfer (FET) cycles.

METHODS

This retrospective study analysed a total of 2315 delivery cycles of day 5 single blastocyst transfer in FET cycles, including 489, 761 and 1103 live-born infants segregated according to a day 3 embryo cell number of <8, 8 and >8 cells, respectively. The neonatal outcomes of the three groups were compared.

RESULTS

The day 3 embryo cell number did not significantly affect the incidence of monozygotic twins. The sex ratio increased as the day 3 embryo cell number increased, but the difference was not statistically significant. There were no significant differences in the rates of preterm birth or low birth weight among the three groups. The rates of stillbirths and neonatal deaths were also not significantly different among the three groups. Moreover, the day 3 embryo cell number did not increase the risk of birth defects in newborns.

CONCLUSIONS

The day 3 embryo cell number did not significantly affect neonatal outcomes.

Live birth rate and neonatal outcomes following interventional embolization of hydrosalpinx

BACKGROUND

Hydrosalpinx has a negative effect on the pregnancy outcomes of in vitro fertilization and embryo transfer (IVF-ET), and the pretreatment for hydrosalpinx play an important role in improving the outcomes of IVF-ET. This study aimed to investigate the impacts of interventional embolization of hydrosalpinx on the live birth rate and neonatal outcome after in-vitro fertilization.

METHOD

In the present retrospective study, 3351 women receiving the first frozen embryo transfer (FET) after freeze-all policy were reviewed. Patients who received interventional embolization of hydrosalpinx (n = 1268) were included in the study group and those with hydrosalpinx-free bilateral fallopian tube obstruction (n = 2083) in the control group. The primary outcome was live birth (LB) rate; the secondary endpoints included rates of implantation, clinical pregnancy (CP), multiple pregnancy, and pregnancy loss.

RESULTS

The LB rate was similar between embolization group (39.91%) and control group (43.21%) (P > 0.05). The rate of implantation (35.81% vs. 32.24%), CP (50.84% vs. 47%) and multiple pregnancy rate (28.71% vs. 24.16%) in the control group were significantly higher than in the embolization group (P < 0.05). The miscarriage rate (39.91%, vs 43.21%, P > 0.05), ectopic gestation rate (2.35% vs 2.83%, P > 0.05), and ongoing pregnancy rate (41.56% vs 44.89%, P > 0.05) were comparable between two groups. After adjustment for confounding factors, interventional embolization of hydrosalpinx was found to have no influence on the LB rate. The thicker endometrium, more embryos transferred, and transfer of blastocyst stage embryos significantly increased the LB rate and CP rate.

CONCLUSION

The interventional embolization of hydrosalpinx can achieve the LB rate similar to that of hydrosalpinx-free obstruction patients with less risk, less pain and reduced medical cost. Thus, embolization of hydrosalpinx is one of the preferable clinical treatments for patients with hydrosalpinx.

Evidence and consensus on technical aspects of embryo transfer

BACKGROUND

Ultrasound-guided embryo transfer (US-GET) is a widely performed procedure, but standards for the best practice are not available.

OBJECTIVE AND RATIONALE

This document aims to provide an overview of technical aspects of US-GET after considering the published data and including the preparation for the embryo transfer (ET) procedure, the actual procedure, the post-procedure care, associated pathologies, complications and risks, quality assurance and practitioners’ performance.

SEARCH METHODS

A literature search for evidence on key aspects of the ET procedure was carried out from database inception to November 2021. Selected papers (n = 359) relevant to the topic were analysed by the authors. The following key points were considered in the papers: whether ultrasound (US) practice standards were explained, to what extent the ET technique was described and whether complications or incidents and how to prevent such events were reported. In the end, 89 papers could be used to support the recommendations in this document, which focused on transabdominal US-GET.

OUTCOMES

The relevant papers found in the literature search were included in the current document and described according to the topic in three main sections: requirements and preparations prior to ET, the ET procedure, and training and competence for ET. Recommendations are provided on preparations prior to ET, equipment and materials, ET technique, possible risks and complications, training and competence. Specific aspects of the laboratory procedures are covered, in particular the different loading techniques and their potential impact on the final outcomes. Potential future developments and research priorities regarding the ET technique are also outlined.

LIMITATIONS, REASONS FOR CAUTION

Many topics were not covered in the literature review and some recommendations were based on expert opinions and are not necessarily evidence based.

WIDER IMPLICATIONS

ET is the last procedural step in an ART treatment and is a crucial step toward achieving a pregnancy and live birth. The current paper set out to bring together the recent developments considering all aspects of ET, especially emphasizing US quality imaging. There are still many questions needing answers, and these can be subject of future research.

STUDY FUNDING/COMPETING INTEREST(S)

No funding. ADA has received royalties from CRC Press and personal honorarium from Cook, Ferring and Cooper Surgical. The other co-authors have no conflicts of interest to declare that are relevant to the content of this article.

Ultrasound Images under an Optimized Image Processing Algorithm in Guiding the Neurological Safety of Resection of Lumbar Disc Nucleus Pulposus in Spinal Surgery

This study was aimed at investigating the effect of an optimized image processing algorithm in ultrasound images and the influence of resection of lumbar disc nucleus pulposus in spinal surgery under the guidance of ultrasound images on the neurological safety of patients. A total of 60 patients with lumbar disc herniation were selected and divided randomly into the control group and observation group. Patients from the control group were treated with resection of lumbar disc nucleus pulposus by an X-ray-guided foraminal microscope, and patients from the observation group underwent the ultrasound image-guided surgeries with an optimized image processing algorithm. Then, the treatment of patients from the two groups was compared. The results showed that the radiotherapy time in the control group was 120 ± 6.3 min and the radiotherapy dose was 129 ± 10.3 min/sec, while the radiotherapy time in the observation group was 4.5 ± 1.2 min and the radiotherapy dose was 22 ± 7.7 min/sec. The time and dose of radiotherapy in the observation group were significantly lower than those in the control group (P < 0.05). In the control group, the numbers of significant effective cases, effective cases, and ineffective cases were 8, 16, and 6, respectively, while those in the observation group were 12, 18, and 0, respectively. The comparison between the groups showed that the number of effective cases and the number of effective cases in the observation group were significantly higher than those in the control group, and the number of ineffective cases was significantly lower than that in the control group (P < 0.05). In conclusion, ultrasound-guided percutaneous foraminal lumbar discectomy could improve patients' clinical symptoms, promote clinical efficacy, and reduce postoperative pain symptoms, thereby accelerating the postoperative rehabilitation of patients. Moreover, it was extremely safe for the nerves.

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

BACKGROUND

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

OBJECTIVE AND RATIONALE

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

SEARCH METHODS

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

OUTCOMES

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

WIDER IMPLICATIONS

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

Outcomes of Frozen Oocyte Donor In Vitro Fertilization (IVF) Cycles Using Fresh Versus Frozen Sperm

The ability to use frozen sperm for insemination during in vitro fertilization (IVF) is crucial for patients and for reproductive endocrinologists. However, concerns exist regarding the effects of cryopreservation on sperm quality and IVF outcomes. This study compares outcomes of frozen donor oocyte IVF cycles with intracytoplasmic sperm injection (ICSI) of good quality fresh versus frozen ejaculated sperm. Patients who underwent their first frozen donor oocyte IVF cycle between 2013 and 2019 at Mayo Clinic were identified. The primary outcome was live birth rate (LBR). Secondary outcomes included fertilization rate (FR), blastocyst development rate (BR), and clinical pregnancy rate (CPR). Twenty-six patients used fresh sperm and 19 patients utilized frozen sperm; there were no significant demographic differences between the groups. There were no significant differences noted in CPR, FR, and BR. Although the LBR was not statistically different when frozen versus fresh sperm was utilized (52.6% vs. 61.5%, p = 0.55), there was a distinct trend towards improved outcomes with fresh sperm that may be clinically significant. This data suggests that frozen sperm may be an alternative to a fresh sample, however fresh sperm may ultimately be a better option. This finding should be further explored with studies utilizing a larger sample size.

Long-term GnRH agonist pretreatment before frozen embryo transfer improves pregnancy outcomes in women with adenomyosis

RESEARCH QUESTION

Do frozen embryo transfer (FET) cycles following long-term gonadotrophin-releasing hormone agonist (GnRHa) pretreatment have better pregnancy outcomes than fresh embryo transfer cycles with long or ultra-long GnRHa protocol in these patients?

DESIGN

This study included 537 women with adenomyosis divided into three groups: (Group A) FET cycles following long-term GnRHa pretreatment (192 patients); (Group B) fresh embryo transfer cycles with the ultra-long GnRHa protocol (241 patients); (Group C) fresh embryo transfer cycles with the long GnRHa protocol (104 patients).

RESULTS

The total gonadotrophin dose and stimulation duration were significantly lower in Group A than in Groups B and C. The implantation and live birth rates were significantly higher in Group A than in Groups B and C. In the long-term GnRHa pretreatment and FET treatment of Group A, implantation (odds ratio [OR] 1.729, 95% confidence interval [CI] 1.073-2.788, P = 0.025), clinical pregnancy (OR 1.665, 95% CI 1.032-2.686, P = 0.037) and live birth rates (OR 1.694, 95% CI 1.045-2.746, P = 0.033) increased and miscarriage rate (OR 0.203, 95% CI 0.078-0.530, P = 0.001) decreased when compared with Group C. Comparison of Groups A and B showed that with the long-term GnRHa pretreatment, FET was a protective factor for live birth rate (OR 1.350, 95% CI 1.017-1.792, P = 0.038).

CONCLUSION

FET following long-term GnRHa pretreatment has a better IVF/intracytoplasmic sperm injection outcome, and a potential benefit in terms of a lower gonadotrophin dose, and a shorter stimulation duration than fresh embryo transfer combined with a long or ultra-long GnRHa protocol.

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.

Sildenafil Supplementation for Women Undergoing Infertility Treatments: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The aim of this systematic review and meta-analysis is to summarize data on the effectiveness of Sildenafil supplementation for women undergoing assisted reproduction techniques. This meta-analysis of randomized controlled trials (RCTs) evaluates the effects of Sildenafil administration during infertility treatments compared with a control group in infertile women. Outcomes evaluated were endometrial thickness (ETh) and the clinical pregnancy rate (CPR). The chemical pregnancy rate (ChPR) was also evaluated. Pooled results were expressed as the risk ratio (RR) or mean differences (MD) with a 95% confidence interval (95% CI). Women undergoing ovulation induction who received Sildenafil showed higher ETh and a higher CPR in comparison to controls. In this group, both the ETh and ChPR resulted in significantly higher values only with delayed start administration. Women undergoing fresh or frozen embryo transfer who received Sildenafil showed no significant advantages regarding ETh and CPR in comparison to controls. In this group, we found a significantly higher ChPR in women receiving Sildenafil. A subgroup analysis revealed significant advantages regarding ETh with oral administration for women undergoing fresh or frozen embryo transfer. Sildenafil therapy appears to improve endometrial thickness and pregnancy rate in women undergoing timed intercourses but it resulted not effective in IUI and IVF treatments. Further RCTs with rigorous methodology are still mandatory.

Sequential cleavage and blastocyst embryo transfer and IVF outcomes: a systematic review

BACKGROUND

Sequential embryo transfer has been proposed as a way to improve embryo implantation in women for in vitro fertilization (IVF), but the effect on pregnancy outcomes remains ambiguous. This systematic review was conducted to investigate the efficacy of sequential embryo transfer on IVF outcomes.

METHODS

A literature search was performed in the PubMed, Web of Science, Cochrane Library, ScienceDirect and Wanfang databases. Data were pooled using a random- or fixed-effects model according to study heterogeneity. The results are expressed as relative risks (RRs) with 95% confidence intervals (CIs). Heterogeneity was evaluated by the I² statistic. The study protocol was registered prospectively on INPLASY, ID: INPLASY202180019.

RESULTS

Ten eligible studies with 2658 participants compared sequential embryo transfer and cleavage transfer, while four studies with 513 participants compared sequential embryo transfer and blastocyst transfer. The synthesis results showed that the clinical pregnancy rate was higher in the sequential embryo transfer group than in the cleavage embryo transfer group (RR 1.42, 95% CI 1.26-1.60, P< 0.01) for both women who did experience repeated implantation failure (RIF) (RR 1.58, 95% CI 1.17-2.13, P< 0.01) and did not experience RIF (Non-RIF) (RR 1.44, 95% CI 1.20-1.66, P< 0.01). However, sequential embryo transfer showed no significant benefit over blastocyst embryo transfer.

CONCLUSION

The current systematic review demonstrates that sequential cleavage and blastocyst embryo transfer improve the clinical pregnancy rate over conventional cleavage embryo transfer. For women with adequate embryos, sequential transfer could be attempted following careful consideration. More high-grade evidence from prospective randomized studies is warranted.

The position of the euploid blastocyst in the uterine cavity influences implantation

RESEARCH QUESTION

Does the position of the euploid blastocyst in the uterine cavity upon transfer, measured as distance in millimetres (mm) from the fundus (DFF) to the air bubble, influence implantation potential?

DESIGN

A total of 507 single/double euploid frozen embryo transfer (FET) cycles at blastocyst stage were included retrospectively between March 2017 and November 2018 at a single centre. The patients were on average 33.3 years old. The FET were performed in natural cycles (n = 151) or hormone replacement therapy cycles (n = 356).

RESULTS

Of the 507 transfers, 370 (73.0%) resulted in a pregnancy, defined as human chorionic gonadotrophin concentration over 15 mIU/ml, and 341 (67.3%) in a clinical pregnancy, with an implantation rate of 62.0% and ongoing pregnancy rate of 59.6% (302/507). When comparing the number of embryos transferred, the pregnancy rate, clinical pregnancy rate and ongoing pregnancy rate were significantly higher after double-embryo transfer (DET) (P = 0.002: P < 0.001 and P = 0.002). The quality of the blastocyst in the single-embryo transfer group had a positive effect on the pregnancy rate (A versus B, P = 0.016; A versus C, P = 0.003) and clinical pregnancy rate (A versus C, P = 0.013). After performing a multivariate logistic regression analysis to consider the effect of all explanatory variables, a negative effect between DFF and pregnancy (P = 0.001), clinical pregnancy (P = 0.001) and ongoing pregnancy (P = 0.030) was found. When all variables remained constant, an increase of 1 mm of DFF changed the odds of pregnancy by 0.882, of clinical pregnancy by 0.891 and of ongoing pregnancy by 0.925. No significant effect of DFF was found on the miscarriage outcome (P = 0.089).

CONCLUSIONS

The depth of blastocyst replacement inside the uterine cavity may influence the pregnancy, clinical pregnancy and ongoing pregnancy rates and should be considered as an important factor to improve the success of IVF cycles.

Immediate versus delayed frozen embryo transfer in women following a failed IVF-ET attempt: a multicenter randomized controlled trial

BACKGROUND

The optimal time at which to perform a frozen-thawed embryo transfer (FET) following a failed in-vitro fertilization-embryo transfer (IVF-ET) attempt remains elusive to most reproductive experts. Physicians often delay the introduction of FET due to concerns related to potential residual effects of ovarian hyperstimulation which may interfere with the regular menstrual cycle. Moreover, given that most of the published studies on the topic are retrospective and have inconsistent findings, it is crucial to develop evidence-based randomized control guides for clinical practice. Therefore, this well-designed randomized controlled trial (RCT) was conducted to determine whether it is necessary to delay FET for at least one menstrual cycle after the failure of fresh embryo transfer.

METHODS

Infertile women eligible for IVF-ET were invited to participate in this multicenter, randomized, non-inferiority, parallel-group, unblinded, controlled trial at the academic fertility centers of four public hospitals in Chinese Mainland. Infertile women scheduled to receive their first FET cycle after a failed IVF-ET attempt were randomly assigned to either (a) the immediate FET group in which FET was performed in the first menstrual cycle following the failed IVF-ET cycle (n = 366) or (b) the delayed FET group in which FET was performed in the second or subsequent menstrual cycle following the failed IVF-ET cycle (n = 366). All FET cycles were performed during hormone replacement cycles for endometrial preparation. The primary outcome was the ongoing pregnancy, defined as a detectable fetal heart beat beyond twelve weeks of gestation. Secondary outcomes were other pregnancy-related outcomes, maternal and neonatal complications. Analysis was performed by both intention-to-treat and per-protocol principles.

RESULTS

A total of 646 FETs were completed. The frequency of moderate to severe depression and high stress level prior to FET in delayed FET group were significantly higher than that in immediate FET group (10.6% vs 6.1%, p = 0.039; 30.3% vs 22.4%, p = 0.022, respectively). Immediate FET resulted in a higher frequency of clinical pregnancy than did delayed FET (41.7% vs 34.1%), for a relative risk (RR) of 1.23 (95% confidence interval [CI], 1.00-1.50; p = 0.045). Women who underwent immediate FET also had a lower frequency of biochemical pregnancy loss (11.7% vs. 30.6%), with a RR of 0.28 (95% CI 0.23-0.63, p < 0.001), and a higher frequency of embryo implantation (25.2% vs. 20.2%), with a RR of 1.25 (95% CI 1.01-1.53; p = 0.038). Although the ongoing pregnancy and live birth rates did not differ significantly between the immediate FET and delayed FET groups (37.1% vs 30.3%, RR 1.22, 95% CI 0.99-1.52, p = 0.067; 36.5% vs 30.0%, RR 1.22, 95% CI 0.98-1.52, p = 0.079, respectively), a multivariate logistic regression analysis adjusted for potential confounders such as depression and stress levels revealed that the immediate FET group had a significantly higher ongoing pregnancy and live birth rates than the delayed FET group (odds ratio 0.68, 95% CI 0.47-0.99, p = 0.041; odds ratio 0.67, 95% CI 0.46-0.96, p = 0.031). The risks of maternal and neonatal complications were comparable between the two groups.

CONCLUSIONS

In women with a previous failed IVF-ET attempt, immediate FET resulted in higher ongoing pregnancy and live birth rates than delayed FET. These findings warrant caution in the indiscriminate application of a delayed FET strategy when apparent risk of high stress level is perceived.

TRIAL REGISTRATION

ChiCTR2000033313 .

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

STUDY QUESTION

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

SUMMARY ANSWER

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

WHAT IS KNOWN ALREADY

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

STUDY DESIGN, SIZE, DURATION

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

PARTICIPANTS/MATERIALS, SETTING, METHODS

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

MAIN RESULTS AND THE ROLE OF CHANCE

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

LIMITATIONS, REASONS FOR CAUTION

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

WIDER IMPLICATIONS OF THE FINDINGS

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

STUDY FUNDING/COMPETING INTEREST(S)

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

TRIAL REGISTRATION NUMBER

NCT03161119.

TRIAL REGISTRATION DATE

5 April 2017.

DATE OF FIRST PATIENT'S ENROLMENT

26 September 2017.

Evaluation of a strategy for difficult embryo transfers from a prospective series of 2,046 transfers

Objective

To evaluate an embryo transfer strategy for difficult transfers (DiTs).

Design

Prospective, nonrandomized, observational, cohort study

Setting

A hospital fertility center in France.

Patient(s)

Data were collected on all embryo transfers conducted using the strategy between February 2014 and February 2020.

Intervention(s)

Anatomical characteristics that could cause DiT were identified by transvaginal ultrasound and the catheter was adapted accordingly. Transfer was guided by transvaginal ultrasound. After passage through the cervix, a rest period was introduced to allow any contractions to stop before embryo deposition in the uterus.

Main Outcome Measure(s)

The primary criterion was the percentage of pregnancies per transfer (P/T) after an easy transfer (EaT) or a DiT. The secondary criteria included the anatomical causes of DiT and the patients’ levels of discomfort.

Result(s)

Of 2,046 transfers, 257 (12%) were DiTs: minor difficulties (n = 152; 7.4%), major difficulties (n = 96; 4.7%), very significant difficulties (n = 7; 0.3%), or impossible (n = 2; 0.1%). The most common causes of DiTs were endocervical crypts (54%), tortuous cervical canal (36%), and marked uterine anteversions (30%). Several causes were often responsible for DiTs. There was no statistically significant difference in the P/T between the EaTs (n = 1,789, 41%) and all degrees of DiT (n = 257, 37%). In addition, there was no statistically significant difference between the level of patient-reported discomfort in the EaT and DiT groups.

Conclusion(s)

This study demonstrated that an adapted embryo transfer strategy, monitored by transvaginal ultrasound, led to similar pregnancy rates regardless of whether the transfer was easy or difficult.

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.

CHRONIC ENDOMETRITIS IN PATIENTS WITH REPEATED IMPLANTATION FAILURES:EPIDEMIOLOGY, ETIOLOGY, PATHOGENESIS AND OVERCOMING INFERTILITY

Recent evidence indicates that the endometrium plays a much more important role in successful implantation and clinical pregnancy than many other recognized factors. Chronic endometritis (CE) is associated with negative reproductive outcomes, including repeated implantation failures. Streptococcus spp., Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Staphylococcus spp., Corynebacterium and Mycoplasma / Ureaplasmaspp are currently considered the main pathogens of CE. This disease disrupts the architectonics of the endometrium at different levels: first of all, CE promotes changes in the population of immunocompetent cells and, therefore, contributes to the disruption of the local immune response in the endometrium at the time of implantation. Antibiotic treatment for CE improves implantation rates and decreases abortion rates, although there are no well-designed prospective studies to support this conclusion. Considering the insufficient effectiveness of antibiotic therapy for CE, especially in cases of resistance of pathogens, or in the case of viral chronic endometritis, it is necessary to develop schemes with additional use of drugs that affect other etiopathogenetic pathways of development and maintenance of CE. An example of such a treatment can be cytokine therapy, which requires further study regarding the efficacy and safety in CE therapy.

Perinatal outcomes of neonates born from different endometrial preparation protocols after frozen embryo transfer: a retrospective cohort study

BACKGROUND

Previous studies have focused on pregnancy outcomes after frozen embryo transfer (FET) performed using different endometrial preparation protocols. Few studies have evaluated the effect of endometrial preparation on pregnancy-related complications. This study was designed to explore the association between different endometrial preparation protocols and adverse obstetric and perinatal complications after FET.

METHODS

We retrospectively included all FET cycles (n = 12,950) in our hospital between 2010 and 2017, and categorized them into three groups, natural cycles (NC), hormone replacement therapy (HRT) and ovarian stimulation (OS) protocols. Pregnancy-related complications and subsequent neonatal outcomes were compared among groups.

RESULTS

Among all 12,950 FET cycles, the live birth rate was slightly lower for HRT cycles than for NC (HRT vs. NC: 28.15% vs. 31.16%, p < 0.001). The pregnancy loss rate was significantly higher in OS or HRT cycles than in NC (HRT vs. NC: 17.14% vs. 10.89%, p < 0.001; OS vs. NC: 16.44% vs. 10.89%, p = 0.001). Among 3864 women with live birth, preparing the endometrium using OS or HRT protocols increased the risk of preeclampsia, and intrahepatic cholestasis of pregnancy (ICP) in both singleton and multiple deliveries. Additionally, OS and HRT protocols increased the risk of low birth weight (LBW) and small for gestational age (SGA) in both singletons and multiples after FET.

CONCLUSION

Compared with HRT or OS protocols, preparing the endometrium with NC was associated with the decreased risk of pregnancy-related complications, as well as the decreased risk of LBW and SGA after FET.

Decreased number of p16-positive senescent cells in human endometrium as a marker of miscarriage

PURPOSE

The aim of this study was to evaluate whether the number of p16-positive cells in the functional layer of the endometrium could be a useful biomarker to identify women with recurrent implantation failure (RIF) undergoing in vitro fertilization (IVF) at risk of miscarriage.

METHODS

Immunohistochemical staining was performed in 311 endometrial biopsies taken during mid-luteal phase using antibody against p16^INK4A. The percentage of p16-positive cells was determined in luminal, glandular and stromal endometrial cells. After embryo transfer, women were divided into the following groups: unsuccessful embryo implantation (n = 151), miscarriage (n = 66) and live birth (n = 94). The percentage of p16-positive cells in all endometrial compartments was compared among these groups.

RESULTS

We found that the percentages of p16-positive glandular and luminal epithelial endometrial cells were significantly higher in patients with live births compared to women with miscarriage (9.3% vs. 2.9%, P < 0.001; and 35.2% vs. 11.7%, P = 0.001, respectively). This tendency was not confirmed in thе stroma. The cut-off values with p16-positive luminal cells lower than 12.5% and p16-positive glandular cells lower than 3.2% could be predictive factors for miscarriage (AUC 0.80 and 0.79; sensitivity 71.3% and 74.5%; specificity 74.2% and 71.2%, respectively).

CONCLUSION

A decreased number of senescent p16-positive cells could be involved in the implantation failures and aetiology of recurrent miscarriage. Women with history of RIF with reduced populations of p16-positive cells in the endometrial glandular and luminal epithelium may be at greater risk for unsuccessful implantation and miscarriage. The percentage of p16-positive luminal epithelial cells may be clinically useful as a biomarker of miscarriage.

The effect of embryo transfer technique on pregnancy rates in in vitro fertilization-intracytoplasmic sperm injection cycles: A prospective cohort study

Objective:

To investigate whether embryo transfer affects pregnancy rates in in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) treatment.

Materials and Methods:

A total of 2,257 patients who underwent IVF-ICSI treatment between 2012 and 2017 were included in this study. Subjects were categorized according to the embryo transfer technique that was required: group 1 (n=1,657) underwent easy transfer with a soft catheter; group 2 (n=548) received external guidance transfers; and group 3 (n=52) experienced difficult transfers with a stylet. Basal parameters, clinical and laboratory IVF-ICSI outcomes, and clinical pregnancy rates (CPR) were compared between the groups.

Results:

There were no differences between the groups in terms of age, body mass index, smoking status, duration and etiology of infertility, baseline folliclestimulating hormone, luteinizing hormone, estradiol (E₂), thyroid-stimulating hormone, prolactin levels, antral follicle count, duration of stimulation, stimulation protocol, total gonadotropin dose required, peak E₂ levels, progesterone levels, and endometrial thickness on human chorionic gonadotropin administration and transfer days (p>0.05). The numbers of oocytes retrieved, MII and 2PN, fertilization rate, day of embryo transfer, and CPRs were also comparable between the groups (p>0.05).

Conclusion:

Our data suggest that embryo transfer has no impact on pregnancy rates in patients who undergo IVF-ICSI treatment. Further studies with more participants are required to elucidate this situation.

Protein C global assay evaluation in naturally conceived vs. assisted reproduction-achieved twin pregnancies: a prospective longitudinal study

PURPOSE

Protein C global assay tests the global function of the protein C pathway, the most clinically significant anticoagulant pathway in humans. The objective of this study is to assess the difference in protein C global assay levels, throughout twin gestation, in naturally conceiving and ART-treated women.

METHODS

This is a prospective cohort longitudinal study of pregnant women with twin gestation. Protein C Global evaluation was performed on frozen blood samples. Ninety-eight women with twin pregnancy, thirty-eight naturally conceived and sixty following ART, were evaluated on four occasions: during the first, second, and third trimesters, and 6 weeks or later after delivery (baseline).

RESULTS

Protein C global assay levels were lower throughout pregnancy as compared to basal levels in both the naturally conceived and ART-conceived groups. However, protein C global assay levels were similar between the ART-conceived and naturally conceived twin pregnancies in all three trimesters. Perinatal complications were associated with decreased protein C global assay levels during the third trimester, although no difference was encountered between naturally conceived and ART-complicated twin pregnancies.

CONCLUSION

While protein C global assay levels drop during twin pregnancy, there is no difference between ART-conceived and naturally conceived gestations. Decreased levels of protein C global assay during the third trimester were similarly associated with perinatal complications in both groups. Our results imply that twin pregnancy of itself is a more dominant factor for perinatal complications as compared to other factors, such as subfertility or the exposure to ART per se.

A New Concept in Minimally Invasive Embryo Transfer

Considerable variation in embryo transfer (ET) catheter types, diverging opinions on their quality and functionality, complications following the insertion of catheters, low efficiency of the application of ET methods in humans, and their widely varying efficiency in animals demonstrate the need to improve ET methods and to look for new types of catheters. Such an opportunity is offered by the introduction of catheters made of new-generation biomaterials. This study was aimed to introduce a new generation of biomaterials into reproductive biotechnology. New-generation materials were compared with materials that have been used for many years, and the functionality of newly produced catheters was compared in vivo. Five types of biomaterials were tested: polycaprolactone (PCL), dibutyryl chitin (DBC), polypropylene (PP), polyethylene (PE) and polylactide (PLA). The study was carried out in two stages. Firstly, the basic utility parameters such as geometric stability, surface structure and catheter resistance were evaluated. Subsequently, the biocompatibility of selected biomaterials in embryo cultures was examined, and the development potential of the obtained blastocysts was evaluated. In the second stage, in vivo with live animals, the biomaterials were tested for biocompatibility and the obtained catheters were examined for their ET functionality. Efficiency with the use of the newly produced catheters was determined, the quality of the blastocysts obtained after embryo culture in the uterus was assessed, and oviducts were subjected to histopathological examination after embryo transfer. Of the tested biomaterials, only polyethylene (PE) showed adequate biological and material properties and proved suitable for production of ET catheters.

There is a cycle to cycle variation in ovarian response and pre-hCG serum progesterone level: an analysis of 244 consecutive IVF cycles

We aimed to answer one key question, that was not previously addressed as to whether serum progesterone (P_4-hCG day) and its co-variates (estradiol (E_{2-hCG day}) and the number of retrieved oocytes) of a given cycle can be predictive of the subsequent cycle when both cycles are consecutive and comparable for the stimulation protocol, gonadotropin dose and duration of stimulation. We analyzed such 244 consecutive (< 6 months) IVF cycles in 122 patients with GnRH agonist long protocol and found that P₄, E₂ and the number of retrieved oocytes significantly vary between the two cycles. Although P₄ increased (ranging from 4.7 to 266.7%) in the 2nd cycle in 61 patients, E₂ and the number of retrieved oocytes, which are normally positively correlated with P₄ paradoxically decreased in the 41% and 37.7% respectively, of these same 61 patients. When a similar analysis was done in the 54 out of 122 patients (44.3%) in whom serum P₄ was decreased in the 2nd cycle, the mean decrease in P₄ was − 34.1 ± 23.3% ranging from − 5.26 to − 90.1%. E₂ and the number of retrieved oocytes paradoxically increased in the 42.3% and 40.7% of these 54 patients respectively. P₄ remained the same only in the 7 (5.7%) of these 122 patients. These findings indicate that late follicular phase serum P₄ may change unpredictably in the subsequent IVF cycle. The changes are not always necessarily proportional with ovarian response of previous cycle suggesting that growth characteristics and steroidogenic activities of antral cohorts may exhibit considerable cycle to cycle variations.

Assisted hatching of vitrified-warmed blastocysts prior to embryo transfer does not improve pregnancy outcomes

Objective

This study aims to determine the impact of assisted hatching (AH) on pregnancy outcomes in vitrified-warmed blastocyst transfers, and evaluate if embryo expansion or morphology influences outcomes.

Methods

A retrospective cohort study was performed including vitrified-warmed blastocyst transfers at our clinic between 2013 and 2017. Of the 2165 embryo transfers, 1986 underwent laser AH and 179 were non-assisted hatched (NAH). The primary outcome was live birth. Secondary outcomes included conception, implantation, clinical pregnancy, clinical pregnancy loss, and monozygotic twinning (MZT).

Results

AH and NAH groups had similar rates of conception (38.7% vs 42.1%), implantation (26.2% vs 27.3%), clinical pregnancy (29.1% vs 30.3%), clinical pregnancy loss (24.0% vs 17.8%), live birth (19.9% vs 20.5%), and MZT (2.08% vs 2.86%). Five pairs of dichorionic/diamniotic twins resulted from single embryo transfers. AH of embryos with expansion grades ≤3 was associated with lower rates of conception (32.5% vs 44.3%%, p < 0.05) and clinical pregnancy (24.0% vs 32.8%, p < 0.05).

Conclusion

AH prior to transfer of vitrified-warmed blastocysts was not associated with improved pregnancy outcomes. The identification of dichorionic/diamniotic twins from single blastocyst transfers challenges the previously held notion that dichorionic/diamniotic MZTs can only occur from division prior to the blastocyst stage. Prospective studies are needed to validate the novel finding of lower rates of conception and clinical pregnancy after AH in embryos with lower expansion grade.

Evaluation of Uterine Artery Doppler and Estrogen Milieu in Oocyte Donation Pregnancies-A Pilot Study

Oocyte donations (OD) represent 4.5% of all in vitro fertilization (IVF) cycles. While OD pregnancies face increased risks of obstetrical complications, especially pregnancy-induced hypertension and pre-eclampsia (PE), little is known about the physiology and the physiopathology of placentation. We performed a prospective case-control study to analyze uterine artery Doppler pulsatility index (UtA-PI) and serum maternal 17β-estradiol (17β-E) at 11 + 0 to 13 + 6 weeks' gestation in singleton pregnancies with different modes of conception. Study groups were: 55 OD, 48 IVF with autologous oocytes from fresh cycles (Autologous-Fresh IVF), 10 IVF with autologous oocytes from frozen cycles (Autologous-Frozen IVF) and 122 spontaneously conceived pregnancies (SC). The mean UtA-PI and serum maternal 17β-E at 11 to 13 + 6 weeks were significantly lower in OD as compared to SC and autologous IVF, either from fresh or frozen cycles. Oocyte donation presents lower UtA-PI and lower serum 17β-E in the first trimester of pregnancy. The etiology of these particularr differences is likely multifactorial and deserves further investigation.

Progestin-Primed Ovarian Stimulation with Dydrogesterone versus Medroxyprogesterone Acetate in Women with Polycystic Ovarian Syndrome for in vitro Fertilization: A Retrospective Cohort Study

Purpose

Dydrogesterone (DYG) is an alternative progestin in progestin-primed ovarian stimulation (PPOS) protocol with weaker pituitary suppression than medroxyprogesterone acetate (MPA) in normal ovulatory women. However, the endocrinological characteristics, oocyte retrieval and pregnancy outcomes of DYG application in polycystic ovarian syndrome (PCOS) patients undergoing in vitro fertilization (IVF) remain unclear.

Patients and methods

This retrospective cohort study included 420 PCOS patients who underwent controlled ovarian stimulation with human menopausal gonadotropin (hMG) and DYG (n=105) or MPA (n=315) from January 2014 to December 2017. Baseline characteristics of the two groups were balanced with propensity score matching using the nearest-neighbor random matching algorithm in a ratio of 1:3. The primary outcome measure was the number of oocytes retrieved. Other main outcome measures included the number of viable embryos, incidence of premature luteinizing hormone (LH) surge and live birth rate per frozen-thawed embryo transfer (FET) cycle.

Results

A similar number of oocytes was retrieved in the two protocols (16.1±6.5 vs 15.1±10.0, P=0.342). Patients in both groups achieved consistent LH suppression with no premature LH surge detected. In the DYG + hMG group, the mean LH levels were significantly higher than the MPA + hMG group on cycle day 9–11 and trigger day (all P<0.001), and the dose of hMG was significantly lower (1710.7±431.6 vs 1891.3±402.2 IU, P<0.001). No significant between-group differences were found in the number of viable embryos (5.3±3.1 vs 5.0±4.1, P=0.139) and live birth rate per FET cycle (43.5% vs 47.7%, P=0.383). None of the participants experienced moderate-to-severe ovarian hyperstimulation syndrome in either group.

Conclusion

Our results showed that the application of DYG in PPOS protocol could achieve comparable oocyte retrieval and pregnancy outcomes to MPA, but significantly reduce the consumption of gonadotropins in PCOS women for IVF treatment.

A Preclinical Evaluation towards the Clinical Application of Oxygen Consumption Measurement by CERMs by a Mouse Chimera Model

We have developed an automated device for the measurement of oxygen consumption rate (OCR) called Chip-sensing Embryo Respiratory Measurement system (CERMs). To verify the safety and the significance of the OCR measurement by CERMs, we conducted comprehensive tests using a mouse model prior to clinical trials in a human in vitro fertilization (IVF) program. Embryo transfer revealed that the OCR measured by CERMs did not compromise the full-term development of mice or their future fertility, and was positively correlated with adenosine triphosphate (ATP) production and the mitochondrial membrane potential (ΔΨm), thereby indirectly reflecting mitochondrial oxidative phosphorylation (OXPHOS) activity. We demonstrated that the OCR is independent of embryo morphology (the size) and number of mitochondria (mitochondrial DNA copy number). The OCR correlated with the total cell numbers, whereas the inner cell mass (ICM) cell numbers and the fetal developmental rate were not. Thus, the OCR may serve as an indicator of the numbers of trophectoderm (TE) cells, rather than number or quality of ICM cells. However, implantation ability was neither correlated with the OCR, nor the embryo size in this model. This can probably be attributed to the limitation that chimeric embryos contain non-physiological high TE cells counts that are beneficial for implantation. CERMs can be safely employed in clinical IVF owing to it being a safe, highly effective, non-invasive, accurate, and quantitative tool for OCR measurement. Utilization of CERMs for clinical testing of human embryos would provide further insights into the nature of oxidative metabolism and embryonic viability.

Chronic Endometritis: Old Problem, Novel Insights and Future Challenges

Chronic endometritis (CE) is a poorly investigated pathology which has been related to adverse reproductive outcomes, such as implantation failure and recurrent miscarriage. In this paper, we aim to provide an overview of diagnosis, etiology, pathophysiology and treatment of CE, its impact on endometrial microenvironment and its association with infertility. We present a narrative review of the current literatures, synthesizing the findings retrieved from searches of computerized databases. CE is more prevalent in infertile patients. Effective antibiotic treatment of CE seems to improve the pregnancy and live birth rate in patients with unexplained recurrent pregnancy loss (RPL), and increase ongoing pregnancy rate in patients with recurrent implantation failure. In order to increase the diagnostic accuracy, immunohistochemistry is recommended besides the conventional histology. In addition, hysteroscopy could be considered as gold standard tool for diagnosis, considering its high correlation with histological findings. CE, as the chronic inflammation of endometrium, is usually asymptomatic and probably underestimated. Interaction of bacteria with endometrial microenvironment promotes changes in leukocyte population, cytokine production and growth factors which support its negative impact on endometrial receptivity. Nevertheless, standardization of the criteria for histopathological diagnosis and immunohistochemistry technique needs to be defined.

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.

Progesterone elevation on the day of hCG trigger has detrimental effect on live birth rate in low and intermediate ovarian responders, but not in high responders

Progesterone elevation (PE) on the day of hCG trigger is associated with decreased pregnancy outcome in fresh cycles. Evidence for this comes from overall patient estimates that mostly ignore different ovarian responses. To compare the impacts of PE on the day of hCG trigger on live birth rates (LBs) in low, intermediate and high ovarian responders and to explore the cut-off value for PE in different populations according to the ovarian response, we retrospectively analyzed a total of 2,351 patients receiving fresh assisted reproduction technology (ART) transfer cycles with GnRH agonist using a long or short protocol. Trend and multivariate logistic regression analyses were performed to identify the cutoff values of PE and to evaluate the effects of PE on LB rates (LBRs) in different ovarian responders. The study found that PE has a detrimental effect on LBRs in low to intermediate ovarian responders rather than in high responders. The cut-off values for PE were 1.0 ng/mL and 2.0 ng/mL for low and intermediate ovarian responders, respectively. The different associations between PE and LBRs according to ovarian response could more accurately predict the prognosis of the IVF cycle and could be used to optimize the treatment of patients undergoing In Vitro Fertilization (IVF)/ Intracytoplasmic Sperm Injection (ICSI).

Effect of pretreatment with a levonorgestrel-releasing intrauterine system on IVF and vitrified-warmed embryo transfer outcomes in women with adenomyosis

RESEARCH QUESTION

Does the use of a levonorgestrel-releasing intrauterine system (LNG-IUS) improve the ongoing pregnancy rate of vitrified-warmed embryo transfer in women with adenomyosis undergoing IVF?

DESIGN

This retrospective study included 358 women with adenomyosis undergoing IVF. Of these, 134 women were enrolled in the LNG-IUS group and another 224 women were in the control group. All women were screened for adenomyosis by transvaginal ultrasound and magnetic resonance imaging (MRI). There was no significant difference in the ages of women, FSH, cause of infertility, body mass index, total dose of gonadotrophin used and number of oocytes collected between the two groups. All comparisons performed were between patients undergoing vitrified-warmed embryo transfer.

RESULTS

Statistical differences were found in the ongoing pregnancy rates (41.8% vs 29.5%, P = 0.017) between the LNG-IUS group and control group. Logistic regression analysis showed that the odds ratio (OR) of ongoing pregnancy was significantly increased with LNG-IUS usage (adjusted OR = 1.628, 95% confidence interval 1.011-2.622). Also, differences were found in implantation rates (32.1% vs 22.1%, P = 0.005) and clinical pregnancy rates (44% versus 33.5%, P = 0.045) between the LNG-IUS group and control group.

CONCLUSIONS

The results of this study offer some support for evaluating the effect of pretreatment with LNG-IUS in women with adenomyosis in future randomized controlled trials.

Correlation between Ovarian Reserve and Incidence of Ectopic Pregnancy after In Vitro Fertilization and Embryo Transfer

PURPOSE

To elucidate the correlation between ovarian reserve and the incidence of ectopic pregnancy (EP) following in vitro fertilization and embryo transfer (IVF/ET) cycles.

MATERIALS AND METHODS

In this observational study, 430 fresh IVF/ET cycles were examined from patient data of two university hospital infertility clinics. All included patients were positive for β-human chorionic gonadotropin (hCG) at 2 weeks after oocyte retrieval via controlled ovarian stimulation. For each cycle, information on age, duration of infertility, basal follicle stimulating hormone (FSH), anti-Müllerian hormone (AMH), days of ovarian stimulation, numbers of retrieved oocytes and transferred embryos, and pregnancy outcomes was collected. Patients with AMH lower than 1.0 ng/dL or basal FSH higher than 10 mIU/mL were classified into the decreased ovarian reserve (DOR) group, and the remaining patients were classified into the normal ovarian reserve (NOR) group.

RESULTS

In total, 355 cycles showed NOR, and 75 cycles DOR. There were no significant differences between the DOR and NOR groups regarding intrauterine (74.7% vs. 83.4%, respectively) or chemical (14.7% vs. 14.1%, respectively) pregnancies. The DOR group had a higher EP than that of NOR group [10.7% (8/75) vs. 2.5% (9/355), p=0.004]. In both univariate [odds ratio (OR) 5.6, 95% confidence interval (CI) 1.4-9.6, p=0.011] and multivariate (adjusted OR 5.1, 95 % CI 1.1-18.7, p=0.012) analysis, DOR was associated with a higher risk of EP.

CONCLUSION

DOR may be associated with a higher risk of EP in IVF/ET cycles with controlled ovarian stimulation. More careful monitoring may be necessary for pregnant women with DOR.

Current Resources for Evidence-Based Practice, March 2019

A review of new resources to support the provision of evidence-based care for women and infants.

Endometrial scratching for infertile women undergoing a first embryo transfer: a systematic review and meta-analysis of published and unpublished data from randomized controlled trials

OBJECTIVE

To investigate endometrial scratch injury (ESI) as an intervention to improve IVF outcome in women undergoing a first ET.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Infertile women undergoing a first fresh/frozen embryo transfer.

INTERVENTION(S)

We included published and unpublished data from randomized controlled trials in which the intervention group received ESI and controls received placebo or no intervention. Pooled results were expressed as relative risk (RR) with 95% confidence interval (CI). The review protocol was registered in PROSPERO to start the data extraction (CRD42018087786).

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy/live birth rate (OPR/LBR), clinical pregnancy rate (CPR), multiple pregnancy rate (MPR), miscarriage rate (MR), and ectopic pregnancy rate (EPR).

RESULT(S)

Seven studies were included (1,354 participants). We found a nonsignificant difference between groups in terms of OPR/LBR, CPR, MR, MPR, and EPR. Subgroup analysis found that ESI on the day of oocyte retrieval (achieved by a Novak curette) reduced OPR/LBR (RR 0.31, 95% CI 0.14-0.69) and CPR (RR 0.36, 95% CI 0.18-0.71), whereas ESI during the cycle preceding ET (performed through soft devices) had no effect on OPR/LBR and CPR. No difference in the impact of ESI was observed between fresh and frozen embryo transfer.

CONCLUSION(S)

Current evidence does not support performing ESI with the purpose of improving the success of a first ET attempt.

A Proteome Approach Reveals Differences between Fertile Women and Patients with Repeated Implantation Failure on Endometrial Level⁻Does hCG Render the Endometrium of RIF Patients?

Background: The molecular signature of endometrial receptivity still remains barely understood, especially when focused on the possible benefit of therapeutical interventions and implantation-related pathologies. Therefore, the protein composition of tissue and isolated primary cells (endometrial stromal cells, ESCs) from endometrial scratchings of ART (Assisted Reproductive Techniques) patients with repeated implantation failure (RIF) was compared to volunteers with proven fertility during the time of embryo implantation (LH + 7). Furthermore, an analysis of the endometrial tissue of fertile women infused with human chorionic gonadotropin (hCG) was conducted. Methods: Endometrial samples (n = 6 RIF, n = 10 fertile controls) were split into 3 pieces: 1/3 each was frozen in liquid nitrogen, 1/3 fixed in PFA and 1/3 cultured. Protein lysates prepared from fresh frozen tissue were processed for mass spectrometric analysis. Results: Three proteins (EPPK1, BCLAF1 and PTMA) showed a statistically altered abundance in the endometrial tissue of RIF patients. Furthermore, pathways like metabolism, immune system, ferroptosis and the endoplasmic reticulum were altered in RIF patients. Remarkably, endometrial tissues of RIF patients showed a significantly higher (p-value = 9 × 10⁻⁸) protein intensity correlation (Pearson’s correlation coefficient = 0.95) compared to fertile women (Pearson’s correlation coefficient = 0.88). The in vivo infusion of hCG stimulated proteins of endocytosis, HIF1 signalling and chemokine production. Notably, patients suffering from RIF had a clinical pregnancy rate of 19% after the intrauterine infusion of hCG before embryo transfer (ET) compared to their failed previous cycles. Conclusion: Our study showed for the first time that the endometrial proteome composition of RIF patients differs from fertile controls during the window of implantation. The intrauterine infusion of hCG prior to an embryo transfer might improve the chemokine triggered embryo-endometrial dialogue and intensify the angiogenesis and immune response. From a clinical point of view, the hCG infusion prior to an embryo transfer might increase the pregnancy rate of RIF patients.

Effects of a Polymorphism in the Promoter Region of the Follicle-Stimulating Hormone Subunit Beta (FSHB) Gene on Female Reproductive Outcomes

BACKGROUND

Follicle-stimulating hormone (FSH) is essential to the hypothalamic-pituitary-gonadal axis, playing a key role in human reproduction. It is a heterodimer comprised of a hormone-specific β-chain (FSH-β) that is associated with an α-chain. It exerts its biological activities by binding to the FSH receptor (FSHR). The β-subunit, which is encoded by the FSHB gene, is responsible for ensuring binding specificity to the FSHR. There is a promoter polymorphism in this gene, c.-211G>T (rs10835638), upstream of the transcription start site; and in vitro studies have reported that the T allele decreases FSHB transcription in gonadotrophic cells.

AIMS

Investigate the possible effects of the FSHB c.-211G/T polymorphism on hormonal profile and in in vitro fertilization (IVF)/intracytoplasmic sperm injection outcomes in normoovulatory Brazilian women.

METHODS

A cross-sectional study of 140 women (median age = 33 years [CI: 32-34]) with infertility mainly caused by male (n = 85) or tuboperitoneal (n = 55) factors. In this study we evaluated FSH, estradiol, luteinizing hormone (LH), progesterone, prolactin and anti-Mullerian hormone levels, and antral follicle counting (AFC). Genotyping was performed using the TaqMan real-time polymerase chain reaction methodology.

RESULTS

The wild-type allele G was found in 86.4% and the polymorphic allele T in 13.6% of the women respectively. The TT genotype was not found in any women. Women carrying the GT genotype had a poorer response more frequently to controlled ovarian hyperstimulation when compared to individuals with the GG genotype (47.4% vs. 26.5%, p = 0.010), higher LH levels (3.1 IU/mL vs. 2.4 IU/mL, p = <0.001), lower AFC (8.0 vs. 10.0, p = 0.03), oocytes retrieved (3.0 vs. 5.0, p = 0.03), MII (3.0 vs. 4.0, p = 0.02), and embryos (2.0 vs. 3.0, p = 0.02). Despite these findings, no difference was observed in pregnancy rate.

CONCLUSION

Our findings suggest that the FSHB c.-211G/T polymorphism may modestly alter some aspects of the female reproductive system, but they are not associated with significantly different IVF outcomes.