Clinical outcomes for Day 3 double cleavage-stage embryo transfers versus Day 5 or 6 single blastocyst transfer in frozen–thawed cycles: a retrospective comparative analysis

Objective This study aimed to compare the clinical outcomes for transfer of Day 3 (D3) double cleavage-stage embryos and Day 5/6 (D5/6) single blastocysts in the frozen embryo transfer (FET) cycle to formulate a more appropriate embryo transplantation strategy. Methods We retrospectively analyzed 609 FET cycles from 518 women from April 2017 to March 2021. All FETs were assigned to the D3-DET group (transfer of a Day 3 double cleavage-stage embryo), D5-SBT group (transfer of a Day 5 single blastocyst), or D6-SBT group (transfer of a Day 6 single blastocyst). Clinical outcomes were comparatively analyzed. Results There were no significant differences in the biochemical pregnancy rate, clinical pregnancy rate, or ongoing pregnancy rate between the D3-DET and D5-SBT groups, but these rates in the two groups were all significantly higher compared with those in the D6-SBT group. The implantation rate in the D5-SBT group was significantly higher than that in the D3-DET group. The twin pregnancy rate in the D5-SBT and D6-SBT groups was significantly lower than that in the D3-DET group. Conclusion This study suggests that D5-SBT is the preferred option for transplantation. D6-SBT reduces the pregnancy rate, making it a more cautious choice for transfer of such embryos.

The relationship between cannabis use and IVF outcome—a cohort study

Background The effects of cannabis use on male and female reproduction have been the focus of scientific research for decades. Although initial studies raised concerns, more recent studies were reassuring. Considering the recent legalization of recreational use of cannabis in Canada, we sought to analyze IVF outcomes among users and non-users in a single IVF center. Methods This is a retrospective cohort study from a single IVF center assessing IVF outcomes among male-female, non-donor IVF patients that are either cannabis users or non-users. We analyzed the ongoing pregnancy rate as well as oocyte yield, fertilization rate, peak serum estradiol, sperm, and embryo quality. We used the Mann-Whitney test, chi-square test, and Kruskal-Wallis tests where appropriate. Results Overall, the study included 722 patients of which 68 (9.4%) were cannabis users, most defined as light users. The results of the study show similar implantation rate (40.74% vs. 41.13%) and ongoing pregnancy rate (35.2% vs. 29.1%) between the users and non-users, respectively. No significant difference between users and non-users in any of the other analyzed outcomes could be detected. Conclusions The results may provide some reassurance for the lack of any demonstrable detrimental effects of cannabis consumption on IVF outcomes. This study was limited by its retrospective nature, self-reporting of cannabis use, and a small user sample size. A larger prospective study is needed to validate its findings.

A concise infertility work-up results in fewer pregnancies

STUDY QUESTION Is pregnancy success rate after a concise infertility work-up the same as pregnancy success rate after the traditional extensive infertility work-up? SUMMARY ANSWER The ongoing pregnancy rate within a follow-up of 1 year after a concise infertility work-up is significantly lower than the pregnancy success rate after the traditional and extensive infertility work-up. WHAT IS KNOWN ALREADY Based on cost-effectiveness studies, which have mainly focused on diagnosis, infertility work-up has become less comprehensive. Many centres have even adopted a one-stop approach to their infertility work-up. STUDY DESIGN, SIZE, DURATION We performed a historically controlled cohort study. In 2012 and 2013 all new infertile couples (n = 795) underwent an extensive infertility work-up (group A). In 2014 and 2015, all new infertile couples (n = 752) underwent a concise infertility work-up (group B). The follow-up period was 1 year for both groups. Complete follow-up was available for 99.0% of couples in group A and 97.5% in group B. PARTICIPANTS/MATERIALS, SETTING, METHODS The extensive infertility work-up consisted of history taking, a gynaecological ultrasound scan, semen analysis, ultrasonographic cycle monitoring, a timed postcoital test, a timed progesterone and chlamydia antibody titre. A hysterosalpingography (HSG) was advised routinely. The concise infertility work-up was mainly based on history taking, a gynaecological ultrasound scan and semen analysis. A HSG was only performed if tubal pathology was suspected or before the start of IUI. Laparoscopy and hormonal tests were only performed if indicated. Couples were treated according to the diagnosis with either expectant management (if the Hunault prognostic score was >30%), ovulation induction (in case of ovulation disorders), IUI in natural cycles (in case of cervical factor), IUI in stimulated cycles (if the Hunault prognostic score was <30%) or IVF/ICSI (in case of tubal factor, advanced female age, severe male factor and if other treatments remained unsuccessful). The primary outcomes were time to pregnancy and the ongoing pregnancy rates in both groups. The secondary outcomes were the number of investigations, the distribution of diagnoses made, the first treatment (started) after infertility work-up and the mode of conception. MAIN RESULTS AND THE ROLE OF CHANCE The descriptive data, such as age, duration of infertility, type of infertility and lifestyle habits, in both groups were comparable. In group A, more than twice the number of infertility investigations were performed, compared to group B. An HSG was made less frequently in group B (33% versus 42%) and at a later stage. A Kaplan–Meier curve shows a shorter time to pregnancy in group A. Also, a significantly higher overall ongoing pregnancy rate within a follow-up of 1 year was found in group A (58.7% versus 46.8%, respectively, P < 0.001). In group A, more couples conceived during the infertility work-up (14.7% versus 6.5%, respectively, P < 0.05). The diagnosis cervical infertility could only be made in group A (9.3%). The diagnosis unexplained infertility differed between groups, at 23.5% in group A and 32.2% in group B (P < 0.001). LIMITATIONS, REASONS FOR CAUTION This was a historically controlled cohort study; introduction of bias cannot be ruled out. The follow-up rate was similar in the two groups and therefore could not explain the differences in pregnancy rate. WIDER IMPLICATIONS OF THE FINDINGS Re-introduction of an extensive infertility work-up should be considered as it may lead to higher ongoing pregnancy rates within a year. The therapeutic effects of HSG and timing of intercourse may improve the fertility chance. This finding should be verified in a randomized controlled trial. STUDY FUNDING/COMPETING INTEREST(S) No funding was obtained for this study. No conflicts of interest were declared. TRIAL REGISTRATION NUMBER N/A.

Biological and Biochemical factors Predictive of Oocyte survival, Fertilization, Pregnancy in oocyte thawing cycles

Optimization and monitoring of IVF treatments requires good data on the effect and magnitude of clinical factors affecting treatment outcome. Many factors have been known to affect IVF outcomes. Currently there are still no data to predict whether a patient who undergoes In Vitro Fertilization (IVF) cycles can be considered a good candidate for oocyte freezing. The aim of this study was therefore to evaluate which biological and biochemical factors can be predictive of oocyte survival and fertilization, as well as of clinical pregnancy in oocyte thawing cycles. This study showed that none of the factors available on the day of the pick-up is able to predict (in case of oocyte cryopreservation) the success of a subsequent oocyte thawing cycle. Only the transfer of at least one Grade 1 embryo after oocyte thawing cycle has a statistically significant impact on pregnancy. Unfortunately, this cannot be considered an elective factor to guide the clinician and/or the embryologist in choosing patient's treatment as it is not available on the day of the oocyte pick up but it is a result of oocyte thawing. Keywords: Oocyte thawing; Biological and biochemical markers; Fertilization rate; Ongoing pregnancy rate

Luteinising hormone-based protocol versus traditional flexible gonadotropin-releasing hormone antagonist protocol in women with normal ovarian response: study protocol for a non-inferiority trial

IntroductionMany patients demonstrate an insufficient endogenous luteinising hormone (LH) concentration during ovarian stimulation. With traditional fixed or flexible gonadotropin-releasing hormone (GnRH) antagonist protocols, antagonist administration may further reduce LH activity. Previously, we proved that LH can be used as an indicator for the timing and dosage of antagonist. Patients with a persistently low LH concentration during ovarian stimulation may not require antagonists, whereas antagonist administration can affect reproductive outcomes. To further explore this hypothesis, we designed a randomised clinical trial to compare the LH-based flexible GnRH antagonist protocol with traditional flexible GnRH antagonist protocol in women with normal ovarian response.Methods and analysisThis study was a multicentre, parallel, prospective, randomised, non-inferiority study. The primary efficacy endpoint was cumulative ongoing pregnancy rate per cycle. The study aimed to prove the non-inferiority of cumulative ongoing pregnancy rate per cycle with an LH-based flexible GnRH antagonist protocol versus traditional flexible GnRH antagonist protocol. Secondary endpoints were the high-quality embryo rate, clinical pregnancy rate and cancellation rate. Differences in cost-effectiveness and adverse events were evaluated. The cumulative ongoing pregnancy rate per cycle in women with normal ovarian response was 70%. Considering that a non-inferiority threshold should retain 80% of the clinical effect of a control treatment, a minimal clinical difference of 14% (one-sided: α, 2.5%; β, 20%) and a total of 338 patients were needed. Anticipating a 10% drop-out rate, the total number of patients required was 372.Ethics and disseminationThis trial has been approved by the Institutional Ethical Committee of Beijing Chao-Yang hospital. All participants in the trial will provide written informed consent. The study will be conducted according to the principles outlined in the Declaration of Helsinki and its amendments. Results of this study will be disseminated in peer-reviewed scientific journals.Trial registration numberChiCTR1800018077.

Dehydroepiandrosterone Shifts Energy Metabolism to Increase Mitochondrial Biogenesis in Female Fertility with Advancing Age

Female reproductive aging is an irreversible process associated with a decrease in oocyte quality, which is a limiting factor for fertility. Previous studies have shown that dehydroepiandrosterone (DHEA) has been shown to improve in vitro fertilization (IVF) outcomes in older women. Herein, we showed that the decline in oocyte quality with age is accompanied by a significant decrease in the level of bioenergetic metabolism genes. We compared the clinical characteristics between groups of infertile women who either received DHEA or did not. Treatment with DHEA may enhance oocyte quality by improving energy production and metabolic reprogramming in cumulus cells (CCs) of aging women. Our results showed that compared with the group without DHEA, the group with DHEA produced a large number of day-three (D3) embryos, top-quality D3 embryos, and had improved ongoing pregnancy rate and clinical pregnancy rate. This may be because DHEA enhances the transport of oxidative phosphorylation and increases mitochondrial oxygen consumption in CCs, converting anaerobic to aerobic metabolism commonly used by aging cells to delay oocyte aging. In conclusion, our results suggest that the benefit of DHEA supplementation on IVF outcomes in aging cells is significant and that this effect may be mediated in part through the reprogramming of metabolic pathways and conversion of anaerobic to aerobic respiration.

Evaluation of Pregnancy Outcomes of Vitrified-Warmed Blastocyst Transfer before and after Endometrial Receptivity Analysis in Identical Patients with Recurrent Implantation Failure

Background:The clinical value of personalized embryo transfer (pET) guided by the endometrial receptivity analysis (ERA) tests for recurrent implantation failure (RIF) cases is still unclear. The aim of this study is to clarify the efficacy of ERA leading to personalization of the day of embryo transfer (ET) in RIF patients. Methods: A retrospective study was performed for 94 patients with RIF who underwent ERA between July 2015 and December 2019. Pregnancy outcomes in a previous vitrified-warmed blastocyst transfer (previous VBT) and a personalized vitrified-warmed blastocyst transfer (pVBT) in identical patients were compared. The details of each pVBT were further analyzed between patients in a non-displaced group, which indicated “receptive” cases in ERA results and those who were in the displaced group, which indicated “non-receptive” cases. Results:When the pregnancy rate, both per patient and per transfer cycle, of previous VBT and pVBT were compared, a significant increase in pVBT was observed between the two methods (5.3% vs. 62.8%, 4.4% vs. 47.9%, respectively). The pregnancy rates, implantation rates, and clinical pregnancy rates of the first pVBT were significantly higher in the displaced group than the non-displaced group. The cumulative ongoing pregnancy rate of the displaced group tended to be higher compared to that of the non-displaced group in the first pVBT, although the difference was not statistically significant (51.0% vs. 31.1%, [Formula: see text] = 0.06). Conclusions:Our study demonstrates that pVBT guided by ERA tests may improve pregnancy outcomes in RIF patients whose window of implantation (WOI) is displaced, and its effect may be more pronounced at the first pVBT. The displacement of WOI may be considered to be one of the causes of RIF, and its adjustment may contribute to the improvement of pregnancy outcomes in RIF patients.

P–132 Centralized versus local embryologists scoring of blastocyst quality obtained in a large European multicenter clinical trial

Study question Does blastocyst quality scoring by central assessment deviate from local assessment and potentially lead to the selection of a different single blastocyst for transfer? Summary answer Central and local assessment provided the same quality classification (poor / good / top) in 69% of all blastocysts and 63% of all transferred blastocysts. What is known already Blastocyst quality is scored most frequently by three morphological parameters, namely expansion and hatching (EH) status, inner cell mass (ICM) grading and trophectoderm (TE) grading. The score is used to define the quality classification (poor / good / top) which determines which embryo is to be transferred or cryopreserved. Blastocyst scoring and grading can be highly subjective, which does influence the choice for transfer and cryopreservation. Time-lapse imaging technology captures additional input about embryo development as well as enables centralized data storage and sharing for independent central assessments. Study design, size, duration Pooled embryo analysis from a prospective, randomized, multicenter trial (RAINBOW) of 619 women undergoing ovarian stimulation with an individualized dose of follitropin delta in a long GnRH agonist protocol between May 2018 and January 2020. Blastocysts were centrally assessed using time-lapse images by two independent assessors and one adjudicator . Selection of the blastocyst for transfer by local assessment was based on morphological scoring and not on morphokinetic time-lapse parameters. Participants/materials, setting, methods Oocytes were fertilized by ICSI and cultured in the Embryoscopeâ (Vitrolife) up to day 5 for transfer or day 5/6 for cryopreservation. Embryos were assessed as either non-blastocyst or blastocyst. Blastocysts were graded centrally and locally at 116 hrs of development, based on EH status (1–6), ICM (A-D) and TE grading (A-D). Central assessors were blinded to local assessment and embryo transfer selection. Main results and the role of chance In total 4282 embryos were assessed centrally, of which 2046 day 5 embryos (48%) were adjudicated due to a scoring difference of at least one parameter between the two central assessors. In total 38% of day 5 embryos were judged as non-blastocysts and 62% as blastocysts of which 61% (i.e. 38% of all embryos) were determined to be of good or top quality. Identical results in terms of quality classification (poor / good / top) were obtained for 69% of blastocysts between local and central assessment and in 78%, between the two central assessors. Moreover, central and local scoring were identical in 62% for EH status, 53% for ICM grading and 57% for TE grading. For all transferred blastocysts (n = 508), central and local quality assessment was aligned for 63%. The ongoing pregnancy rate following single blastocyst transfer (SBT) was 41% (202/489), and similar to when considering only the transfers for which the central assessment had the same or a higher classification than the local assessment (166/411=40%). In 16% of all SBT, central quality assessment gave a lower score for the transferred blastocyst than the central assessment. This discrepancy could potentially have led to transfer of a different blastocyst. Limitations, reasons for caution This trial included assessments made by embryologists from 20 IVF centres. Some centres has limited experience with time-lapse technology for morphological blastocyst scoring. Scoring could therefore have been affected by differences in focal planes, magnification and contrast compared to inverted microscopy, with potential influence on blastocyst scores and quality classification. Wider implications of the findings: Local and central blastocyst quality classification based on morphology aligns well but remains subjective. Embryo assessment may benefit from using tools like artificial intelligence-based algorithms for a more objective analysis. Trial registration number NCT03564509

P–130 The effect of time of ejaculation and time of processing of semen on fertilization and ongoing pregnancy in IVF/ICSI treatments

Study question Does time between ejaculation and processing, and time between processing and insemination/injection affect fertilization rate (FR) and ongoing pregnancy rate (OPR) in IVF/ICSI treatments? Summary answer Increasing time between processing and insemination significantly decreased the OPR after IVF. FRs after IVF/ICSI and OPR after ICSI were not affected by different time-intervals. What is known already The choice for IVF or ICSI depends on semen quality, however, this doesn’t affect the outcome of IVF/ICSI treatments (Mariappen et al 2018). After ejaculation, the percentage of motile spermatozoa decreases progressively at a rate of about 10%/hour (Makler 1979). According to the ESHRE-guideline, semen should be processed within 1 hour after ejaculation. In our laboratory, a validation was performed that confirmed a decrease in sperm motility after ejaculation. During incubation at 37 °C after processing, the sample remained stable in incubation medium (unpublished data). Therefore, we analyzed the effect of handling time and incubation time with regard to IVF/ICSI outcomes. Study design, size, duration This retrospective data analysis examines the effect of time between ejaculation and processing using density-gradient centrifugation (handling time) and time between processing and insemination (IVF)/injection (ICSI) (incubation time) on the FR and OPR, irrespective of the initial semen quality. A total of 1488 oocyte pickups (844 IVF, 644 ICSI) were included from 1060 patients undergoing fertility treatment between 2017 and 2019. Oocyte pickups without oocytes, with oocyte vitrification, or with donor oocytes were excluded. Participants/materials, setting, methods Anonymized data were obtained from the laboratory database ProMISe. Handling time and incubation time of the semen incubated at 37 °C and 5% CO2 were analyzed in relation to the occurrence of TFF (Total Fertilization Failure), FR and OPR. Linear and logistic regression was performed in SPSS version 25. In case of significant association, the data were adjusted for potential confounders, such as woman’s age, semen quality before and after preparation, and number of oocytes. Main results and the role of chance This study shows that increasing the incubation time of the semen significantly reduced the OPR per ET in IVF treatments (from 30,8% within 3,5 hours to 24,1% after 6 hours) even after adjusting for the potential confouders. However, the OPR in ICSI treatments was not significantly affected by the incubation time (rather, there was an opposite trend). Also, the handling time of the semen did not significant effect the FR per OPU and the OPR per ET in IVF/ICSI treatments. The overall percentage of TFF was 3,5% and did not differ significantly between the IVF and ICSI treatments. Both handling time and incubation time did not have a significant effect on the occurrence of TFF. An explanation for the decrease in OPR in IVF treatments may be that increasing the incubation time at 37 °C reduces the sperm quality as the capacitation reaction takes place too early, energy levels are reduced, DNA damage increases, or vacuoles arise in the sperm heads (Thijssen et al 2014, Jackson et al 2010, Peer et al 2007). Incubation at room temperature and reduction of the insemination time may improve OPR. Limitations, reasons for caution Retrospective study limitations (bias), no data on DNA fragmentation, incubation of semen only at 37 °C after preparation. Wider implications of the findings: Although it is recommended to produce semen at the IVF-department, our results show that an exception can be made, when production of a semen sample in a clinical setting is stressful, with no negative effect on the outcome. Furthermore, incubation-time at room temperature may have a positive effect on OPR. Trial registration number Not applicable