Reassessing the impact of letrozole co-administration in controlled ovarian hyperstimulation: findings from a single-center repeated measures study

PURPOSE

To explore whether letrozole improved outcomes in subsequent controlled ovarian hyperstimulation (COH) cycles.

METHODS

This was a retrospective repeated measures cohort study examining COH cycles. Patients were included if they underwent two cycles for unexplained infertility, male factor infertility, or planned oocyte/embryo cryopreservation. The first cycles for all patients implemented a non-letrozole, conventional gonadotropin protocol. Second cycles for the study group included letrozole (2.5-7.5 mg for 5 days) with no medication change to second cycles amongst controls. Our primary objective was to compare oocyte yield. Cohorts were then subdivided by pursuit of oocyte (OC) or embryo (IVF) cryopreservation. Secondary outcome amongst the OC subgroup was oocyte maturation index (metaphase II (MII)/total oocytes). Secondary outcomes amongst the IVF subgroup were normal fertilization rate (2-pronuclear zygotes (2PN)/oocytes exposed to sperm), blastocyst formation rate (blastocysts/2PNs), and embryo ploidy (%euploid and aneuploid).

RESULTS

Fifty-four cycles (n = 27) were included in letrozole and 108 cycles (n = 54) were included in control. Oocyte yield was higher in second cycles (p < 0.008) in the letrozole group but similar in second cycles (p = 0.26) amongst controls. Addition of letrozole did not impact MII index (p = 0.90); however, MII index improved in second cycles amongst controls (p < 0.001). Both groups had similar rates of normal fertilization (letrozole: p = 0.52; control: p = 0.61), blast formation (letrozole: p = 0.61; control: p = 0.84), euploid (letrozole: p = 0.29; control: p = 0.47), and aneuploid embryos (letrozole: p = 0.17; control: p = 0.78) between cycles.

CONCLUSIONS

Despite improved oocyte yield, letrozole did not yield any difference in oocyte maturation or embryo outcomes.

Coronavirus Disease 2019 (COVID-19) Vaccination and Assisted Reproduction Outcomes: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the association between coronavirus disease 2019 (COVID-19) vaccination and female assisted reproduction outcomes through a systematic review and meta-analysis.

DATA SOURCES

We searched Medline (OVID), EMBASE, Web of Science, Cochrane Library, and ClinicalTrials.gov on January 11, 2023, for original articles on assisted reproduction outcomes after COVID-19 vaccination. The primary outcome was rates of clinical pregnancy; secondary outcomes included number of oocytes retrieved, number of mature oocytes retrieved, fertilization rate, implantation rate, ongoing pregnancy rate, and live-birth rate.

METHODS OF STUDY SELECTION

Two reviewers independently screened citations for relevance, extracted pertinent data, and rated study quality. Only peer-reviewed published studies were included.

TABULATION, INTEGRATION, AND RESULTS

Our query retrieved 216 citations, of which 25 were studies with original, relevant data. Nineteen studies reported embryo transfer outcomes, with a total of 4,899 vaccinated and 13,491 unvaccinated patients. Eighteen studies reported data on ovarian stimulation outcomes, with a total of 1,878 vaccinated and 3,174 unvaccinated patients. There were no statistically significant results among our pooled data for any of the primary or secondary outcomes: clinical pregnancy rate (odds ratio [OR] 0.94, 95% CI 0.88-1.01, P =.10), number of oocytes retrieved (mean difference -0.26, 95% CI -0.68 to 0.15, P =.21), number of mature oocytes retrieved (mean difference 0.31, 95% CI -0.14 to 0.75, P =.18), fertilization rate (OR 0.99, 95% CI 0.87-1.11, P =.83), implantation rate (OR 0.92, 95% CI 0.84-1.00, P =.06), ongoing pregnancy rate (OR 0.95, 95% CI 0.86-1.06, P =.40), or live-birth rate (OR 0.95, 95% CI 0.78-1.17, P =.63). A subanalysis based on country of origin and vaccine type was also performed for the primary and secondary outcomes and did not change the study results.

CONCLUSION

Vaccination against COVID-19 is not associated with different fertility outcomes in patients undergoing assisted reproductive technologies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42023400023.

Live birth rates in in vitro fertilization cycles with five or fewer follicles

PURPOSE

To evaluate live birth rates (LBRs) for in vitro fertilization (IVF) cycles with ≤5 follicles at trigger, with the goal of helping patients with low follicle counts decide whether to proceed to retrieval.

METHODS

This is a retrospective cohort study from an urban, university-affiliated fertility center. All IVF cycles that yielded <10 oocytes between 2016 and 2020 were reviewed. Cycles were included if <5 follicles measuring >14 mm were verified on trigger day. The primary outcome was LBR per retrieval after fresh or frozen transfer. Secondary outcomes were number of oocytes, mature oocytes, 2-pronuclear zygotes (2-PNs), blastocysts for transfer/biopsy, and euploid blastocysts (if preimplantation genetic testing for aneuploidy (PGT-A) was used).

RESULTS

1502 cycles (900 with PGT-A) from 972 patients were included. Mean number of oocytes, mature oocytes, 2-PNs, blastocysts for transfer/biopsy, and euploid blastocysts differed by follicle number (p < 0.001). Across all age groups, there were differences in LBR associated with follicle number (p < 0.001). However, within age groups, not all results were significant. For example, for patients <35 years, LBR did not differ by follicle number and among patients 35-37 years; LBR with two or three follicles was lower than with five (p < 0.02). LBR for patients 35-40 years was <20% with 1-3 follicles and 25-40% with 4-5 follicles. LBR for patients >41 years was <5% with 1-3 follicles and <15% with 4-5 follicles.

CONCLUSION

As expected, LBR is higher with more follicles. Providing patients with <5 follicles with specific data can help them weigh the emotional, physical, and financial costs of retrieval.

Human-induced pluripotent stem cell-derived ovarian support cell co-culture improves oocyte maturation in vitro after abbreviated gonadotropin stimulation

STUDY QUESTION

Can in vitro maturation (IVM) and developmental competence of human oocytes be improved by co-culture with ovarian support cells (OSCs) derived from human-induced pluripotent stem cells (hiPSCs)?

SUMMARY ANSWER

OSC-IVM significantly improves the rates of metaphase II (MII) formation and euploid Day 5 or 6 blastocyst formation, when compared to a commercially available IVM system.

WHAT IS KNOWN ALREADY

IVM has historically shown highly variable performance in maturing oocytes and generating oocytes with strong developmental capacity, while limited studies have shown a positive benefit of primary granulosa cell co-culture for IVM. We recently reported the development of OSCs generated from hiPSCs that recapitulate dynamic ovarian function in vitro.

STUDY DESIGN, SIZE, DURATION

The study was designed as a basic science study, using randomized sibling oocyte specimen allocation. Using pilot study data, a prospective sample size of 20 donors or at least 65 oocytes per condition were used for subsequent experiments. A total of 67 oocyte donors were recruited to undergo abbreviated gonadotropin stimulation with or without hCG triggers and retrieved cumulus-oocyte complexes (COCs) were allocated between the OSC-IVM or control conditions (fetal-like OSC (FOSC)-IVM or media-only IVM) in three independent experimental design formats. The total study duration was 1 April 2022 to 1 July 2023.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Oocyte donors between the ages of 19 and 37 years were recruited for retrieval after informed consent, with assessment of anti-Mullerian hormone, antral follicle count, age, BMI and ovarian pathology used for inclusion and exclusion criteria. In experiment 1, 27 oocyte donors were recruited, in experiment 2, 23 oocyte donors were recruited, and in experiment 3, 17 oocyte donors and 3 sperm donors were recruited. The OSC-IVM culture condition was composed of 100 000 OSCs in suspension culture with hCG, recombinant FSH, androstenedione, and doxycycline supplementation. IVM controls lacked OSCs and contained either the same supplementation, FSH and hCG only (a commercial IVM control), or FOSCs with the same supplementation (Media control). Experiment 1 compared OSC-IVM, FOSC-IVM, and a Media control, while experiments 2 and 3 compared OSC-IVM and a commercial IVM control. Primary endpoints in the first two experiments were the MII formation (i.e. maturation) rate and morphological quality assessment. In the third experiment, the fertilization and embryo formation rates were assessed with genetic testing for aneuploidy and epigenetic quality in blastocysts.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed a statistically significant improvement (∼1.5×) in maturation outcomes for oocytes that underwent IVM with OSCs compared to control Media-IVM and FOSC-IVM in experiment 1. More specifically, the OSC-IVM group yielded a MII formation rate of 68% ± 6.83% SEM versus 46% ± 8.51% SEM in the Media control (P = 0.02592, unpaired t-test). FOSC-IVM yielded a 51% ± 9.23% SEM MII formation rate which did not significantly differ from the media control (P = 0.77 unpaired t-test). Additionally, OSC-IVM yielded a statistically significant ∼1.6× higher average MII formation rate at 68% ± 6.74% when compared to 43% ± 7.90% in the commercially available IVM control condition (P = 0.0349, paired t-test) in experiment 2. Oocyte morphological quality between OSC-IVM and the controls did not significantly differ. In experiment 3, OSC-IVM oocytes demonstrated a statistically significant improvement in Day 5 or 6 euploid blastocyst formation per COC compared to the commercial IVM control (25% ± 7.47% vs 11% ± 3.82%, P = 0.0349 logistic regression). Also in experiment 3, the OSC-treated oocytes generated blastocysts with similar global and germline differentially methylated region epigenetic profiles compared commercial IVM controls or blastocysts after either conventional ovarian stimulation.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

While the findings of this study are compelling, the cohort size remains limited and was powered on preliminary pilot studies, and the basic research nature of the study limits generalizability compared to randomized control trials. Additionally, use of hCG-triggered cycles results in a heterogenous oocyte cohort, and potential differences in the underlying maturation state of oocytes pre-IVM may limit or bias findings. Further research is needed to clarify and characterize the precise mechanism of action of the OSC-IVM system. Further research is also needed to establish whether these embryos are capable of implantation and further development, a key indication of their clinical utility.

WIDER IMPLICATIONS OF THE FINDINGS

Together, these findings demonstrate a novel approach to IVM with broad applicability to modern ART practice. The controls used in this study are in line with and have produced similar to findings to those in the literature, and the outcome of this study supports findings from previous co-culture studies that found benefits of primary granulosa cells on IVM outcomes. The OSC-IVM system shows promise as a highly flexible IVM approach that can complement a broad range of stimulation styles and patient populations. Particularly for patients who cannot or prefer not to undergo conventional gonadotropin stimulation, OSC-IVM may present a viable path for obtaining developmentally competent, mature oocytes.

STUDY FUNDING/COMPETING INTEREST(S)

A.D.N., A.B.F., A.G., B.P., C.A., C.C.K., F.B., G.R., K.S.P., K.W., M.M., P.C., S.P., and M.-J.F.-G. are shareholders in the for-profit biotechnology company Gameto Inc. P.R.J.F. declares paid consultancy for Gameto Inc. P.C. also declares paid consultancy for the Scientific Advisory Board for Gameto Inc. D.H.M. has received consulting services from Granata Bio, Sanford Fertility and Reproductive Medicine, Gameto, and Buffalo IVF, and travel support from the Upper Egypt Assisted Reproduction Society. C.C.K., S.P., M.M., A.G., B.P., K.S.P., G.R., and A.D.N. are listed on a patent covering the use of OSCs for IVM: U.S. Provisional Patent Application No. 63/492,210. Additionally, C.C.K. and K.W. are listed on three patents covering the use of OSCs for IVM: U.S. Patent Application No. 17/846,725, U.S Patent Application No. 17/846,845, and International Patent Application No.: PCT/US2023/026012. C.C.K., M.P.S., and P.C. additionally are listed on three patents for the transcription factor-directed production of granulosa-like cells from stem cells: International Patent Application No.: PCT/US2023/065140, U.S. Provisional Application No. 63/326,640, and U.S. Provisional Application No. 63/444,108. The remaining authors have no conflicts of interest to declare.

The Landscape of Telomere Length and Telomerase in Human Embryos at Blastocyst Stage

The telomere length of human blastocysts exceeds that of oocytes and telomerase activity increases after zygotic activation, peaking at the blastocyst stage. Yet, it is unknown whether aneuploid human embryos at the blastocyst stage exhibit a different profile of telomere length, telomerase gene expression, and telomerase activity compared to euploid embryos. In present study, 154 cryopreserved human blastocysts, donated by consenting patients, were thawed and assayed for telomere length, telomerase gene expression, and telomerase activity using real-time PCR (qPCR) and immunofluorescence (IF) staining. Aneuploid blastocysts showed longer telomeres, higher telomerase reverse transcriptase (TERT) mRNA expression, and lower telomerase activity compared to euploid blastocysts. The TERT protein was found in all tested embryos via IF staining with anti-hTERT antibody, regardless of ploidy status. Moreover, telomere length or telomerase gene expression did not differ in aneuploid blastocysts between chromosomal gain or loss. Our data demonstrate that telomerase is activated and telomeres are maintained in all human blastocyst stage embryos. The robust telomerase gene expression and telomere maintenance, even in aneuploid human blastocysts, may explain why extended in vitro culture alone is insufficient to cull out aneuploid embryos during in vitro fertilization.

Fertility-Sparing Treatment and Assisted Reproductive Technology in Patients with Endometrial Carcinoma and Endometrial Hyperplasia: Pregnancy Outcomes after Embryo Transfer

The goal of fertility-sparing treatment (FST) for patients desiring future fertility with EMCA, and its precursor EH, is to clear the affected tissue and revert to normal endometrial function. Approximately 15% of patients treated with FST will have a live birth without the need for assisted reproductive technology (ART). Despite this low number, little information exists on the pregnancy outcomes of patients who utilize ART. The purpose of this study was to evaluate pregnancy outcomes following embryo transfer in patients with EMCA or EH who elected for FST. This retrospective cohort study at a large urban university-affiliated fertility center included all patients who underwent embryo transfer after fertility-sparing treatment for EMCA or EH between January 2003 and December 2018. Primary outcomes included embryo transfer results and a live birth rate (defined as the number of live births per number of transfers). There were 14 patients, three with EMCA and 11 with EH, who met the criteria for inclusion with a combined total of 40 embryo transfers. An analysis of observed outcomes by sub-group, compared to the expected outcomes at our center (patients without EMCA/EH matched for age, embryo transfer type and number, and utilization of PGT-A) showed that patients with EMCA/EH after FST had a significantly lower live birth rate than expected (Z = −5.04, df = 39, p < 0.01). A sub-group analysis of the 14 euploid embryo transfers resulted in a live birth rate of 21.4% compared to an expected rate of 62.8% (Z = −3.32, df = 13, p < 0.001). Among patients with EMCA/EH who required assisted reproductive technology, live birth rates were lower than expected following embryo transfer when compared to patients without EMCA/EH at our center. Further evaluation of the impact of the diagnosis, treatment, and repeated cavity instrumentation for FST is necessary to create an individualized and optimized approach for this unique patient population.

Serum Gonadotropin Levels Predict Post-Trigger Luteinizing Hormone Response in Antagonist Controlled Ovarian Hyperstimulation Cycles

The objective of this study was to investigate the utility of using serum gonadotropin levels to predict optimal luteinizing hormone (LH) response to gonadotropin releasing hormone agonist (GnRHa) trigger. A retrospective cohort study was performed of all GnRH-antagonist controlled ovarian hyperstimulation (COH) cycles at an academic fertility center from 2017-2020. Cycles that utilized GnRHa alone or in combination with human chorionic gonadotropin (hCG) for trigger were included. Patient and cycle characteristics were collected from the electronic medical record. Optimal LH response was defined as a serum LH ≥ 40 mIU/mL on the morning after trigger. Total sample size was 3865 antagonist COH cycles, of which 91% had an optimal response to GnRHa trigger. Baseline FSH (B-FSH) and earliest in-cycle LH (EIC-LH) were significantly higher in those with optimal response. Multivariable logistic regression affirmed association of optimal response with EIC-LH, total gonadotropin dosage, age, BMI and Asian race. There was no difference in the number of oocytes retrieved (p = 0.14), maturity rate (p = 0.40) or fertilization rates (p = 0.49) based on LH response. There was no difference in LH response based on use of combination vs. GnRHa alone trigger (p = 0.21) or GnRHa trigger dose (p = 0.46). The EIC-LH was more predictive of LH trigger response than B-FSH (p < 0.005).The optimal B-FSH and EIC-LH values to yield an optimal LH response was ≥ 5.5 mIU/mL and ≥ 1.62 mIU/mL, respectively. In an era of personalized medicine, utilizing cycle and patient characteristics, such as early gonadotropin levels, may improve cycle outcomes and provide further individualized care.

Vanquishing multiple pregnancy in in vitro fertilization in the United States-a 25-year endeavor

The practice of in vitro fertilization has changed tremendously since the birth of the first in vitro fertilization infant in 1978. With the success of early in vitro fertilization programs in the United States, there was a substantial rise in twin births nationwide. In the mid-1990s, more than 30% of in vitro fertilization cycles resulted in twin or higher-order multifetal pregnancies. Since that time, we not only have witnessed improvements in laboratory and treatment efficacy but also have seen a dramatic impact on pregnancy outcomes, specifically regarding twin pregnancies. Because the field evolved and the risks of multifetal pregnancies became more salient, in 2019, the rate of twin pregnancies had dropped to <7% of cycles. This improvement was largely because of technical advancements and revised professional guidance: culturing embryos longer before transfer, improved freezing technology, embryo preimplantation genetic testing, and revised professional guidance regarding the number of embryos to transfer. These developments have led to single-embryo transfer becoming the standard of care in most scenarios. We used national in vitro fertilization surveillance data of all autologous in vitro fertilization cycles from 1996 to 2019 to illustrate trends in the following improved outcomes: autologous embryo transfer cycles involving blastocyst-stage embryos, vitrified embryos, preimplantation genetic testing cycles, total number of embryos being transferred per cycle, and single-embryo transfer usage over time. Among deliveries from autologous embryo transfers, we highlighted trends in singleton births over time and proportion of deliveries involving twins, triplets, quadruplets, or greater. The notable progress in reducing the rate of multifetal pregnancies with in vitro fertilization was largely attributed to a series of technical and clinical actions, culminating in an 80% reduction in the incidence of multiple births without a loss in overall treatment effectiveness.

Oocyte stimulation parameters influence the number and proportion of mature oocytes retrieved in assisted reproductive technology cycles

PURPOSE

Whether differences in stimulation parameters alter the number and proportion of MII oocytes retrieved.

METHODS

Records of 2546 patients were examined, looking at age, day 2/3 follicle-stimulating hormone (FSH) and estradiol (E2) levels, total dose of gonadotropins administered (including FSH and human menopausal gonadotropin [hMG]), fraction of hMG administered, number of days of treatment with gonadotropins, and the dose of gonadotropins administered per day. We segregated the patients into 3 different classes depending on the trigger method used and 2 groups based on egg freeze vs. ICSI. Multiple regression methods were used to examine associations between stimulation parameters and the total number of eggs, number of immature oocytes (Poisson regression), and the fraction of retrieved oocytes that were immature (Logistic regression).

RESULTS

After adjustments for different triggers and egg freeze versus ICSI, both the #immature oocytes and the immature fraction of oocytes were associated with the total gonadotropin dose (inversely) and the gonadotropin dose/day (positively). Other parameters were associated with the number of immature oocytes but were also associated with the number of oocytes retrieved.

CONCLUSIONS

Stimulations using less total gonadotropin and more gonadotropin per day were associated with more immaturity. The type of trigger method used for final maturation was associated with immaturity but was believed to be predominantly due to trigger assignment to patients based on response. The association between use of ICSI and less immaturity was believed to be due to additional time for maturation in the ICSI group.

Self-reported quality of life scales in women undergoing oocyte freezing versus in vitro fertilization

PURPOSE

The objective of this study was to investigate stress levels among women undergoing elective oocyte cryopreservation by comparing their self-reported quality of life measures with women undergoing in vitro fertilization during the fertility treatment cycle.

METHODS

Patients undergoing oocyte retrieval at a single institution were offered a voluntary, anonymous, and written questionnaire. The survey was adapted and validated from the Fertility Quality of Life tool to assess self-reported fertility treatment-related problems and was tested for construct validity and reliability. Based on exploratory factor analyses, three subscales were created as follows: fertility treatment-related stress, tolerability, and environment. Relationships between patient characteristics and fertility treatment-related measures were examined with Fisher's exact test, ANOVA, and multivariate regression with significance p < 0.05.

RESULTS

A total of 461 patients (331 IVF, 130 egg freeze) were included in the analysis. Medically indicated egg freezing patients were excluded. Overall, both IVF and egg freeze patients reported stress during the current fertility cycle and there were no significant differences between IVF and egg freeze patients for any subscale scores. Three sets of generalized linear models were run and found age to be associated with fertility treatment-related stress and tolerability scores, with younger patients experiencing greater difficulties. Additionally, patients who underwent repeat cycles reported more fertility treatment-related stress.

CONCLUSIONS

Patients undergoing egg freezing have similar responses to quality of life questions as patients undergoing IVF. Repeat cycles and younger age contribute to perceptions of stress. This information supports developing stress reduction strategies for all women undergoing egg freezing.

Follicle size indicates oocyte maturity and blastocyst formation but not blastocyst euploidy following controlled ovarian hyperstimulation of oocyte donors

STUDY QUESTION

Is there is an association between follicle size and the quality of oocytes retrieved from them as judged by ability to achieve the blastocyst stage, blastocyst grades and blastocyst ploidy?

SUMMARY ANSWER

Although follicle size is a valuable predictor of oocyte maturity and is a significant predictor of the ability of a fertilized oocyte to become a quality blastocyst, the ploidy of each quality blastocyst is not related to the size of the follicle from which its oocyte was retrieved.

WHAT IS KNOWN ALREADY

It is unclear whether the oocytes within larger follicles are the best oocytes of the cohort. Although there have been studies examining follicle size in relation to embryo quality, there has been no study relating the incidence of euploidy in embryos to follicle size.

STUDY DESIGN, SIZE, DURATION

The purpose of this study was to examine follicle sizes and the oocytes from those follicles (and the embryos that result from those oocytes) to see if there is an association between follicle size and the quality of oocytes as judged by ability to achieve the blastocyst stage, blastocyst grades and blastocyst ploidy. Follicle sizes for oocytes were assessed both as diameters (mm) and as Z values (expressed as their size relative to the mean and standard deviation of that donor’s follicular cohort). Comparisons were made using cumulative histograms, rolling averages and receiver operator characteristic (ROC) curves and its AUC.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Twenty-two oocyte donors (ages: 24.5 ± 3.5 years) whose recipients would use ICSI for insemination were enrolled in this study. Follicles were aspirated one-at-a-time to be certain that the aspirated oocyte was from the same follicle measured. The follicle measurement (size) was noted in the embryology records. Oocytes were cultured individually throughout their time in the embryology laboratory so that follicle sizes could be uniquely associated with each oocyte. Oocytes and embryos were analyzed according to the size of the follicle from which the oocyte was retrieved.

MAIN RESULTS AND THE ROLE OF CHANCE

Three hundred seventeen oocytes (96.1%) had an associated follicle size. Of the oocytes with follicle sizes, 255 (80.4%) had a polar body (MII), and 60 (18.9%) were immature: 31 (9.8%) with a visible germinal vesicle (GV stage) and 29 (9.1%) with neither a polar body nor a visible germinal vesicle (MI). The incidence of MII oocytes was significantly associated with larger follicle size using either mm (ROC’s AUC = 0.87; P &lt; 0.0001) or Z values (ROC’s AUC = 0.86; P &lt; 0.0001). Among MII oocytes there was no association with follicle size for the appearance of 228 oocytes with two pronuclei (2 PN). Among 2 PN’s, the development of 94 quality blastocysts that underwent trophectoderm biopsy (TE Bx) exhibited a significant association with larger follicles using either mm (ROC’s AUC = 0.59; P = 0.01) or Z values (ROC’s AUC = 0.57; P = 0.01). The use of follicle diameter as a feature to distinguish between fertilized oocytes that would ultimately become blastocysts versus those that would not become blastocysts resulted in an enrichment for blastocyst formation from 20 to 40%. Of the 94 quality blastocysts, 51 were determined by next generation sequencing (NGS) to be euploid.Although oocyte maturity and the incidence of blastocyst formation were associated with follicle size, the incidence of euploidy among biopsied blastocysts was not. Follicles measured by two different methods (mm or Z values) led to predominantly the same conclusions.

LIMITATIONS, REASONS FOR CAUTION

This study investigated the relationship between follicle size and measures of oocyte/embryo quality when donors were treated similarly. Therefore, this study does not investigate the effects of triggering and retrieving oocytes when the follicle cohorts are of different sizes or lead follicles are of different sizes. Although no association was found between follicle size and euploid blastocysts, the fact that blastocyst ploidy is not entirely dependent upon oocyte ploidy (e.g. aneuploidies derived from mitotic errors or from the fertilizing sperm) makes it difficult to infer the relationship between follicle diameter and oocyte ploidy.

WIDER IMPLICATIONS OF THE FINDINGS

It is confirmed that follicle diameter is predictive of oocyte maturity. However, once oocyte maturity is known, the diameter of the follicle from which the oocyte was retrieved is not instructive. Embryos generated through fertilization and development of the mature oocytes from any observed follicle diameter were equally likely to become euploid blastocysts.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by ReproART: Georgian American Center for Reproductive Medicine. None of the authors declare any actual conflicts of interest. D.H.M. received compensation from ReproART, Biogenetics Corporation and the Sperm and Embryo Bank of New York and honoraria and travel funding from Ferring Pharmaceuticals and from Granata Bio. S.M. received compensation from Cooper Genomics and an honorarium and travel funding from Ferring Pharmaceuticals. L.C. is the founder of LTD Ovamedi, the organization that represents Cooper Genomics in Georgia, and received travel funding from the European Society for Human Reproduction and Embryology.

TRIAL REGISTRATION NUMBER

N/A.

Beyond the biopsy: predictors of decision regret and anxiety following preimplantation genetic testing for aneuploidy

STUDY QUESTION

What factors are associated with decision regret and anxiety following preimplantation genetic testing for aneuploidy (PGT-A)?

SUMMARY ANSWER

The majority of patients viewed PGT-A favourably regardless of their outcome; although patients with negative outcomes expressed greater decision regret and anxiety.

WHAT IS KNOWN ALREADY

PGT-A is increasingly utilized in in vitro fertilization (IVF) cycles to aid in embryo selection. Despite the increasing use of PGT-A technology, little is known about patients’ experiences and the possible unintended consequences of decision regret and anxiety related to PGT-A outcome.

STUDY DESIGN, SIZE, DURATION

Anonymous surveys were distributed to 395 patients who underwent their first cycle of autologous PGT-A between January 2014 and March 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

There were 69 respondents who underwent PGT-A at a university-affiliated fertility centre, completed the survey and met inclusion criteria. Respondents completed three validated questionnaires including the Brehaut Decision Regret (DR) Scale, short-form State-Trait Anxiety Inventory (STAI-6) and a health literacy scale. The surveys also assessed demographics, fertility history, IVF and frozen embryo transfer cycle data.

MAIN RESULTS AND THE ROLE OF CHANCE

The majority of respondents were Caucasian, >35 years of age and educated beyond an undergraduate degree. The majority utilized PGT-A on their first IVF cycle, most commonly to ‘maximize the efficiency of IVF’ or reduce per-transfer miscarriage risk. The overall median DR score was low, but 39% of respondents expressed some degree of regret. Multiple regression confirmed a relationship between embryo ploidy and decision regret, with a lower number of euploid embryos associated with a greater degree of regret. Patients who conceived following euploid transfer reported less regret than those who miscarried or failed to conceive (P < 0.005). Decision regret was inversely associated with number of living children but not associated with age, education, race, insurance coverage, religion, marital status or indication for IVF/PGT-A. Anxiety was greater following a negative pregnancy test or miscarriage compared to successful conception (P < 0.0001). Anxiety was negatively associated with age, time since oocyte retrieval and number of living children, and a relationship was observed between anxiety and religious affiliation. Overall, decision regret was low, and 94% of all respondents reported satisfaction with their decision to pursue PGT-A; however, patients with a negative outcome were more likely to express decision regret and anxiety.

LIMITATIONS, REASON FOR CAUTION

This survey was performed at a single centre with a relatively homogenous population, and the findings may not be generalizable. Reasons for caution include the possibility of response bias and unmeasured differences among those who did and did not respond to the survey, as well as the possibility of recall bias given the retrospective nature of the survey. Few studies have examined patient perceptions of PGT-A, and our findings should be interpreted with caution.

WIDER IMPLICATIONS OF THE FINDINGS

Overall decision regret was low following PGT-A, and the vast majority deemed the information gained valuable for reproductive planning regardless of outcome. However, more than one-third of the respondents expressed some degree of regret. Respondents with no euploid embryos were more likely to express regret, and those with a negative outcome following euploid embryo transfer expressed both higher regret and anxiety. These data identify unanticipated consequences of PGT-A and suggest opportunities for additional counselling and support surrounding IVF with PGT-A.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was obtained for this study. D.H.M. reports personal fees, honorarium, and travel expenses from Ferring Pharmaceuticals, personal fees and travel expenses from Granata Bio, and personal fees from Biogenetics Corporation, The Sperm and Embryo Bank of New York, and ReproART: Georgian American Center for Reproductive Medicine. All conflicts are outside the submitted work.

A Comparison of Pregnancy Outcomes in Patients Undergoing Donor Egg Single Embryo Transfers With and Without Preimplantation Genetic Testing

Two of the many milestone developments in the field of assisted reproduction have been oocyte donation and preimplantation genetic testing for aneuploidy (PGT-A). Because it has been demonstrated that even young women produce a meaningful proportion of aneuploid embryos, screening out such abnormalities could potentially increase the efficacy of donor egg (DE) cycles. In this retrospective cohort study, we investigated the effect of PGT-A on DE cycle outcomes, including implantation rate (IR), spontaneous abortion rate (SABR), and ongoing pregnancy/live birth rate. We used fresh and frozen donor cycles not using PGT-A as comparison groups; all cases involved single embryo transfer. Data analysis revealed that PGT-A did not improve pregnancy outcome metrics in DE cycles, although there was a trend toward decreasing the SABR. There was a significant increase in IR with fresh cycles outperforming all frozen cycles. Overall, these results suggest that the benefits of performing PGT-A on embryos derived from young DEs may be limited and that there is an effect of the freezing process on pregnancy outcomes. These findings may provide useful insights into the science and practice of PGT-A across all of its applications.

Cairo consensus on the IVF laboratory environment and air quality: report of an expert meeting

This proceedings report presents the outcomes from an international Expert Meeting to establish a consensus on the recommended technical and operational requirements for air quality within modern assisted reproduction technology (ART) laboratories. Topics considered included design and construction of the facility, as well as its heating, ventilation and air conditioning system; control of particulates, micro-organisms (bacteria, fungi and viruses) and volatile organic compounds (VOCs) within critical areas; safe cleaning practices; operational practices to optimize air quality while minimizing physicochemical risks to gametes and embryos (temperature control versus air flow); and appropriate infection-control practices that minimize exposure to VOC. More than 50 consensus points were established under the general headings of assessing site suitability, basic design criteria for new construction, and laboratory commissioning and ongoing VOC management. These consensus points should be considered as aspirational benchmarks for existing ART laboratories, and as guidelines for the construction of new ART laboratories.

Localized accumulation of cytosolic calcium near the fused sperm is associated with the calcium- and voltage-dependent block of sperm entry in the sea urchin egg

Interaction of the sperm and egg depolarizes the egg membrane, allowing the sperm to enter; however, if the egg membrane is not allowed to depolarize from its resting potential (e.g., by voltage-clamp), the sperm will not enter. Previous studies demonstrated that sperm entry into sea urchin eggs that are voltage-clamped at negative membrane potentials is regulated both by the egg's membrane potential and a voltage-dependent influx of calcium into the egg. In these cases, electrical or cytoplasmic continuity (sperm-egg membrane fusion) occurs at negative membrane potentials, but subsequent loss of cytoplasmic continuity results in failure of sperm entry (unfusion). The work presented herein examined where, in relation to the sperm, and when, in relation to the sperm-induced electrophysiological events, the egg's calcium influx occurs, and how these events relate to successful or failed sperm entry. When sperm entered the egg, elevation of intracellular calcium concentration ([Ca²⁺ ]_i ) began near the fused sperm on average 5.9 s after sperm-egg membrane fusion. Conversely, when sperm failed to enter the egg, [Ca²⁺ ]_i elevated near the site of sperm-egg fusion on average 0.7 s after sperm-egg membrane fusion, which is significantly earlier than in eggs for which sperm entered. Therefore, the accumulation of calcium near the site of sperm-egg fusion is spatially and temporally consistent with the mechanism that may be responsible for loss of cytoplasmic continuity and failure of sperm entry.