No major differences in perinatal and maternal outcomes between uninterrupted embryo culture in time-lapse system and conventional embryo culture

STUDY QUESTION

Is embryo culture in a closed time-lapse system associated with any differences in perinatal and maternal outcomes in comparison to conventional culture and spontaneous conception?

SUMMARY ANSWER

There were no significant differences between time-lapse and conventional embryo culture in preterm birth (PTB, <37 weeks), low birth weight (LBW, >2500 g) and hypertensive disorders of pregnancy for singleton deliveries, the primary outcomes of this study.

WHAT IS KNOWN ALREADY

Evidence from prospective trials evaluating the safety of time-lapse incubation for clinical use show similar embryo development rates, implantation rates, and ongoing pregnancy and live birth rates when compared to conventional incubation. Few studies have investigated if uninterrupted culture can alter risks of adverse perinatal outcomes presently associated with IVF when compared to conventional culture and spontaneous conceptions.

STUDY DESIGN, SIZE, DURATION

This study is a Swedish population-based retrospective registry study, including 7379 singleton deliveries after fresh embryo transfer between 2013 and 2018 from selected IVF clinics. Perinatal outcomes of singletons born from time-lapse-cultured embryos were compared to singletons from embryos cultured in conventional incubators and 71 300 singletons from spontaneous conceptions. Main perinatal outcomes included PTB and LBW. Main maternal outcomes included hypertensive disorders of pregnancy (pregnancy hypertension and preeclampsia).

PARTICIPANTS/MATERIALS, SETTING, METHODS

From nine IVF clinics, 2683 singletons born after fresh embryo transfer in a time-lapse system were compared to 4696 singletons born after culture in a conventional incubator and 71 300 singletons born after spontaneous conception matched for year of birth, parity, and maternal age. Patient and treatment characteristics from IVF deliveries were cross-linked with the Swedish Medical Birth Register, Register of Birth Defects, National Patient Register and Statistics Sweden. Children born after sperm and oocyte donation cycles and after Preimplantation Genetic testing cycles were excluded. Odds ratio (OR) and adjusted OR were calculated, adjusting for relevant confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

In the adjusted analyses, no significant differences were found for risk of PTB (adjusted OR 1.11, 95% CI 0.87-1.41) and LBW (adjusted OR 0.86, 95% CI 0.66-1.14) or hypertensive disorders of pregnancy; preeclampsia and hypertension (adjusted OR 0.99, 95% CI 0.67-1.45 and adjusted OR 0.98, 95% CI 0.62-1.53, respectively) between time-lapse and conventional incubation systems. A significantly increased risk of PTB (adjusted OR 1.31, 95% CI 1.08-1.60) and LBW (adjusted OR 1.36, 95% CI 1.08-1.72) was found for singletons born after time-lapse incubation compared to singletons born after spontaneous conceptions. In addition, a lower risk for pregnancy hypertension (adjusted OR 0.72 95% CI 0.53-0.99) but no significant difference for preeclampsia (adjusted OR 0.87, 95% CI 0.68-1.12) was found compared to spontaneous conceptions. Subgroup analyses showed that some risks were related to the day of embryo transfer, with more adverse outcomes after blastocyst transfer in comparison to cleavage stage transfer.

LIMITATIONS, REASONS FOR CAUTION

This study is retrospective in design and different clinical strategies may have been used to select specific patient groups for time-lapse versus conventional incubation. The number of patients is limited and larger datasets are required to obtain more precise estimates and adjust for possible effect of additional embryo culture variables.

WIDER IMPLICATIONS OF THE FINDINGS

Embryo culture in time-lapse systems is not associated with major differences in perinatal and maternal outcomes, compared to conventional embryo culture, suggesting that this technology is an acceptable alternative for embryo incubation.

STUDY FUNDING/COMPETING INTEREST(S)

The study was financed by a research grant from Gedeon Richter. There are no conflicts of interest for all authors to declare.

TRIAL REGISTRATION NUMBER

N/A.

Good practice recommendations on add-ons in reproductive medicine†

STUDY QUESTION

Which add-ons are safe and effective to be used in ART treatment?

SUMMARY ANSWER

Forty-two recommendations were formulated on the use of add-ons in the diagnosis of fertility problems, the IVF laboratory and clinical management of IVF treatment.

WHAT IS KNOWN ALREADY

The innovative nature of ART combined with the extremely high motivation of the patients has opened the door to the wide application of what has become known as 'add-ons' in reproductive medicine. These supplementary options are available to patients in addition to standard fertility procedures, typically incurring an additional cost. A diverse array of supplementary options is made available, encompassing tests, drugs, equipment, complementary or alternative therapies, laboratory procedures, and surgical interventions. These options share the common aim of stating to enhance pregnancy or live birth rates, mitigate the risk of miscarriage, or expedite the time to achieving pregnancy.

STUDY DESIGN, SIZE, DURATION

ESHRE aimed to develop clinically relevant and evidence-based recommendations focusing on the safety and efficacy of add-ons currently used in fertility procedures in order to improve the quality of care for patients with infertility.

PARTICIPANTS/MATERIALS, SETTING, METHODS

ESHRE appointed a European multidisciplinary working group consisting of practising clinicians, embryologists, and researchers who have demonstrated leadership and expertise in the care and research of infertility. Patient representatives were included in the working group. To ensure that the guidelines are evidence-based, the literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, recommendations were based on the professional experience and consensus of the working group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 46 independent international reviewers. A total of 272 comments were received and incorporated where relevant.

MAIN RESULTS AND THE ROLE OF CHANCE

The multidisciplinary working group formulated 42 recommendations in three sections; diagnosis and diagnostic tests, laboratory tests and interventions, and clinical management.

LIMITATIONS, REASONS FOR CAUTION

Of the 42 recommendations, none could be based on high-quality evidence and only four could be based on moderate-quality evidence, implicating that 95% of the recommendations are supported only by low-quality randomized controlled trials, observational data, professional experience, or consensus of the development group.

WIDER IMPLICATIONS OF THE FINDINGS

These guidelines offer valuable direction for healthcare professionals who are responsible for the care of patients undergoing ART treatment for infertility. Their purpose is to promote safe and effective ART treatment, enabling patients to make informed decisions based on realistic expectations. The guidelines aim to ensure that patients are fully informed about the various treatment options available to them and the likelihood of any additional treatment or test to improve the chance of achieving a live birth.

STUDY FUNDING/COMPETING INTEREST(S)

All costs relating to the development process were covered from ESHRE funds. There was no external funding of the development process or manuscript production. K.L. reports speakers fees from Merck and was part of a research study by Vitrolife (unpaid). T.E. reports consulting fees from Gynemed, speakers fees from Gynemed and is part of the scientific advisory board of Hamilton Thorne. N.P.P. reports grants from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare, speakers fees from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare. S.R.H. declares being managing director of Fertility Europe, a not-for-profit organization receiving financial support from ESHRE. I.S. is a scientific advisor for and has stock options from Alife Health, is co-founder of IVFvision LTD (unpaid) and received speakers' fee from the 2023 ART Young Leader Prestige workshop in China. A.P. reports grants from Gedeon Richter, Ferring Pharmaceuticals and Merck A/S, consulting fees from Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos and Merck A/S, speakers fees from Gedeon Richter, Ferring Pharmaceuticals, Merck A/S, Theramex and Organon, travel fees from Gedeon Richter. The other authors disclosed no conflicts of interest.

DISCLAIMER

This Good Practice Recommendations (GPRs) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation.ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or bedeemedinclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results.Theydo not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type.Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.

O-104 Providing accurate information – impact of ancestry testing

Providing information to patients and, or donors at the ART clinic is essential but challenging, especially in the case of reproductive donation.

Recent developments in direct-to-consumer genetic testing combined with social media have increased the degree of difficulty. Concepts such as donor anonymity, secrecy and disclosure have to be revisited and totally re-thought as the anonymity of donors, their relatives and also of the children born through donation is no longer guaranteed.

This potentially has significant effects on everyone involved: to donors who donated under the assumption that their donation was completely anonymous, to recipients who were under the impression that they could keep donor conception a secret and to donor offspring who were unaware of their donor-assisted conception. It is also effectively retrospective affecting everyone who has, is or might participate.

Providing the correct information to donors, ART couples and donor-conceived offspring is the key, and advise for such information provision will be presented in line with the recently published ESHRE good practice recommendations for information provision for those involved in reproductive donation.

Trial registration number

P-793 The effect of Nuclear Receptor Subfamily 5 Group A Member 1 (NR5A1) in human ovarian somatic cell development

Study question

Can an inducible NR5A1 (encoding Steroidogenic Factor 1) cell line be used to study the functional role of NR5A1 in human female gonadal differentiation?

Summary answer

Conditional induction of NR5A1 in a human pluripotent stem cell (hPSC)-based model of gonadal differentiation allows us to study its effect on the differentiating cells.

What is known already

According to animal studies, NR5A1 is a critical factor in gonadal development. Previous research in our lab showed that CRISPR/Cas9 induced upregulation of NR5A1 during gonadal differentiation in male (XY) hPSCs increases expression of early Sertoli cell markers such as Inhibin A and Anti-Müllerian hormone (AMH) and thus pushes the cells into a more mature gonadal cell type. However, the role of NR5A1 in female gonadal differentiation has yet to be determined.

Study design, size, duration

The female (XX) human embryonic stem cell (hESC) line, H9, was edited using CRISPR/Cas9 to conditionally induce NR5A1. These cells were subjected to a 10/20-day gonadal differentiation protocol where NR5A1 was induced through addition of Doxycycline (DOX) and Trimethoprim (TMP) from day 4 until day 10/20. Starting from day 4 technical duplicates/triplicates from every second day were subjected to qRT-PCR. Technical triplicates from day 4, 6, 8 and 10 were subjected to bulk RNA-sequencing.

Participants/materials, setting, methods

The cell line that was used in this project is a female hESC line, H9 (WiCell). A previously established protocol for gonadal differentiation (Sepponen et al., 2017) was followed wherein different cell culture media and matrices were supplemented with small molecules, inhibitors and growth factors. The CRISPR/Cas9 genome-editing system was used to generate the NR5A1 inducible cell line. Cell characterisation was performed using qRT-PCR and bulk RNA sequencing (NovaSeq S4) methods.

Main results and the role of chance

qRT-PCR results showed that without NR5A1 induction there was almost no expression of this gene, but its expression increased drastically upon addition of DOX and TMP to the culture media. NR5A1 induction seemed to upregulate FOXL2 and WNT4, which are crucial genes for female gonadal differentiation, although the increase was not statistically significant. AMH showed a significant increase on day 8 of differentiation after NR5A1 induction. We also saw an increase in the expression of steroidogenic genes such as STAR, CYP11A1, CYP17A1 and CYP19A1 after NR5A1 induction. Subjecting the cells to NR5A1 induction for an additional 10 days resulted in the upregulation of bipotential gonadal markers GATA4, WT1 and EMX2 after NR5A1 induction. Similarly, the female gonadal markers RSPO1 and WNT4 were upregulated over time and WNT4 expression further increased upon NR5A1 induction.

NovaSeq S4 data showed that on day 8, after induction of NR5A1, genes related to reproductive system development and female pregnancy were upregulated. These included DHH, NR5A1, CYP19A1, AR, INHA and NR0B1. On day 10 genes related to reproductive system development such as FOXL2, NR5A1, INHA, LHCGR, and NR0B1 were also upregulated after NR5A1 induction.

Limitations, reasons for caution

The effect of NR5A1 induction on expression levels of bipotential gonadal markers GATA4, LHX9, WT1, EMX2 and female gonadal markers FOXL2, RSPO1, WNT4 was small in comparison to differentiation without additional NR5A1 induction. Moreover, we lack a protocol to generate bipotential gonadal cells expressing NR5A1 without inducing NR5A1 through CRISPR/Cas9.

Wider implications of the findings

Taken together the results will provide valuable insight and novel information on the function of NR5A1 in early female gonadal development and more in general on human ovarian development and sex determination. This knowledge will increase our understanding of pathological gonadal development, which often underlies disorders of sex development.

Trial registration number

Not applicable

P–767 Cumulative live birth rate after IVF - trend over time and the impact of blastocyst culture and vitrification

Study question

Has cumulative live birth rate (CLBR) improved over time and which factors are associated with such an improvement?

Summary answer

During 2007–2017, CLBR per oocyte aspiration increased significantly (27.0% to 36.3%), in parallel with an increase in blastocyst transfer and cryopreservation by vitrification.

What is known already

While it has been shown that live birth rate (LBR) per embryo transfer (ET) is higher for fresh blastocyst than for fresh cleavage stage embryo transfer, CLBR per oocyte aspiration, including one fresh ET and all subsequent frozen embryo transfers (FET), does not seem to differ between the two culture strategies.

Study design, size, duration

STUDY DESIGN, SIZE, DURATION: National register study including all oocyte aspirations performed in Sweden 2007–2017, n = 124 700. Donation cycles excluded.

Participants/materials, setting, methods

Data were retrieved from the Swedish National Registry of Assisted Reproduction (Q-IVF). CLBR was defined as the number of deliveries with at least one live birth resulting from one oocyte aspiration, including all fresh and/or frozen embryo transfers within one year. The delivery of a singleton, twin, or other multiples was registered as one delivery. Cryopreservation of cleavage stage embryos was performed by slow freezing and of blastocyst by vitrification.

Main results and the role of chance

Overall, the CLBR per oocyte aspiration increased significantly during the study period, from 27.0% to 36.3% (OR 1.039, 95% CI 1.035–1.043) and from 30.0% to 43.3% if at least one ET was performed (AOR 1.055, 95% CI 1.050–1.059). The increase in CLBR was independent of maternal age, number of oocytes retrieved and number of previous IVF live births. The CLBR for women &lt;35 years and ≥ 35 years both increased significantly, following the same pattern. During the study period a substantially increasing number of blastocyst transfers were performed, both in fresh and in FET cycles. An important contributor included in the blastocyst strategy, may be the extended culture of the total cohort of embryos, also embryos earlier discarded at early cleavage stages, in order to reach the blastocyst stage. These embryos may contribute to the total number of available blastocysts and thereby increase the chance of a live birth within that oocyte aspiration cycle. Other important predicting factors for live birth, such as number of embryos transferred, could not explain the improvement, on the contrary the single embryo transfer (SET) rate increased with time.

Limitations, reasons for caution

The retrospective design implicates that other confounders of importance for CLBR can not be ruled out. In addition, some FET cycles might be performed later than one year post oocyte aspiration for the last year (2017) and are thus not included in this study.

Wider implications of the findings: The results suggest that blastocyst transfer, particularly when used in FET cycles and in combination with vitrification, is an important contributor to the improved live birth rates over time. This gives a possibility for fewer oocyte aspirations needed to achieve a live birth and a shortened time to live birth.

Trial registration number

-

P-767 Cumulative live birth rate after IVF - trend over time and the impact of blastocyst culture and vitrification

Study question

Has cumulative live birth rate (CLBR) improved over time and which factors are associated with such an improvement?

Summary answer

During 2007-2017, CLBR per oocyte aspiration increased significantly (27.0 % to 36.3 %), in parallel with an increase in blastocyst transfer and cryopreservation by vitrification.

What is known already

While it has been shown that live birth rate (LBR) per embryo transfer (ET) is higher for fresh blastocyst than for fresh cleavage stage embryo transfer, CLBR per oocyte aspiration, including one fresh ET and all subsequent frozen embryo transfers (FET), does not seem to differ between the two culture strategies.

Study design, size, duration

STUDY DESIGN, SIZE, DURATION: National register study including all oocyte aspirations performed in Sweden 2007-2017, n = 124 700. Donation cycles excluded.

Participants/materials, setting, methods

Data were retrieved from the Swedish National Registry of Assisted Reproduction (Q-IVF). CLBR was defined as the number of deliveries with at least one live birth resulting from one oocyte aspiration, including all fresh and/or frozen embryo transfers within one year. The delivery of a singleton, twin, or other multiples was registered as one delivery. Cryopreservation of cleavage stage embryos was performed by slow freezing and of blastocyst by vitrification.

Main results and the role of chance

Overall, the CLBR per oocyte aspiration increased significantly during the study period, from 27.0 % to 36.3 % (OR 1.039, 95% CI 1.035-1.043) and from 30.0 % to 43.3 % if at least one ET was performed (AOR 1.055, 95% CI 1.050-1.059). The increase in CLBR was independent of maternal age, number of oocytes retrieved and number of previous IVF live births. The CLBR for women &lt; 35 years and ≥ 35 years both increased significantly, following the same pattern. During the study period a substantially increasing number of blastocyst transfers were performed, both in fresh and in FET cycles. An important contributor included in the blastocyst strategy, may be the extended culture of the total cohort of embryos, also embryos earlier discarded at early cleavage stages, in order to reach the blastocyst stage. These embryos may contribute to the total number of available blastocysts and thereby increase the chance of a live birth within that oocyte aspiration cycle. Other important predicting factors for live birth, such as number of embryos transferred, could not explain the improvement, on the contrary the single embryo transfer (SET) rate increased with time.

Limitations, reasons for caution

The retrospective design implicates that other confounders of importance for CLBR can not be ruled out. In addition, some FET cycles might be performed later than one year post oocyte aspiration for the last year (2017) and are thus not included in this study.

Wider implications of the findings

The results suggest that blastocyst transfer, particularly when used in FET cycles and in combination with vitrification, is an important contributor to the improved live birth rates over time. This gives a possibility for fewer oocyte aspirations needed to achieve a live birth and a shortened time to live birth.

Trial registration number

-

Global and local visual processing in autism - a co-twin-control study

BACKGROUND

Autism Spectrum Disorder (ASD) is associated with altered global and local visual processing. However, the nature of these alterations remains controversial, with contradictory findings and notions ranging from a reduced drive to integrate information into a coherent 'gestalt' ("weak central coherence" = WCC) to an enhanced perceptual functioning (EPF) in local processing.

METHODS

This study assessed the association between autism and global/local visual processing, using a large sample of monozygotic (MZ) and dizygotic (DZ) twins (N = 290, 48% females, age = 8-31 years). The Fragmented Pictures Test (FPT) assessed global processing, whereas local processing was estimated with the Embedded Figures Test (EFT) and the Block Design Test (BDT). Autism was assessed both categorically (clinical diagnosis), and dimensionally (autistic traits). Associations between visual tasks and autism were estimated both across the cohort and within-twin pairs where all factors shared between twins are implicitly controlled.

RESULTS

Clinical diagnosis and autistic traits predicted a need for more visual information for gestalt processing in the FPT across the cohort. For clinical diagnosis, this association remained within-pairs and at trend-level even within MZ twin pairs alone. ASD and higher autistic traits predicted lower EFT and BDT performance across the cohort, but these associations were lost within-pairs.

CONCLUSIONS

In line with the WCC account, our findings indicate an association between autism and reduced global visual processing in children, adolescents and young adults (but no evidence for EPF). Observing a similar association within MZ twins suggests a non-shared environmental contribution.

Social Cognition in Autism and Other Neurodevelopmental Disorders: A Co-twin Control Study

Alterations in social cognition (SC) are hypothesized to underlie social communication and interaction challenges in autism spectrum disorder (ASD). The aetiological underpinnings driving this association remain unclear. We examined SC in 196 twins with ASD, other neurodevelopmental disorders or typical development using the naturalistic Movie for the Assessment of Social Cognition. Autism and its severity were assessed with the Autism Diagnostic Observation Schedule-2, and autistic traits with the Social Responsiveness Scale-2. Using within twin-pair regression models, controlling for age, sex, IQ, and unmeasured familial confounders such as genetic background and shared-environment, SC correlated with ASD diagnosis, autism severity, and autistic traits. Our findings highlight the importance of SC alterations in autism and suggest a non-shared environmental impact on the association.

Recent developments in genetics and medically assisted reproduction: from research to clinical applications

Two leading European professional societies, the European Society of Human Genetics and the European Society for Human Reproduction and Embryology, have worked together since 2004 to evaluate the impact of fast research advances at the interface of assisted reproduction and genetics, including their application into clinical practice. In September 2016, the expert panel met for the third time. The topics discussed highlighted important issues covering the impacts of expanded carrier screening, direct-to-consumer genetic testing, voiding of the presumed anonymity of gamete donors by advanced genetic testing, advances in the research of genetic causes underlying male and female infertility, utilisation of massively parallel sequencing in preimplantation genetic testing and non-invasive prenatal screening, mitochondrial replacement in human oocytes, and additionally, issues related to cross-generational epigenetic inheritance following IVF and germline genome editing. The resulting paper represents a consensus of both professional societies involved.

Recent developments in genetics and medically-assisted reproduction: from research to clinical applications†‡

Two leading European professional societies, the European Society of Human Genetics and the European Society for Human Reproduction and Embryology, have worked together since 2004 to evaluate the impact of fast research advances at the interface of assisted reproduction and genetics, including their application into clinical practice. In September 2016, the expert panel met for the third time. The topics discussed highlighted important issues covering the impacts of expanded carrier screening, direct-to-consumer genetic testing, voiding of the presumed anonymity of gamete donors by advanced genetic testing, advances in the research of genetic causes underlying male and female infertility, utilisation of massively-parallel sequencing in preimplantation genetic testing and non-invasive prenatal screening, mitochondrial replacement in human oocytes, and additionally, issues related to cross-generational epigenetic inheritance following IVF and germline genome editing. The resulting paper represents a consensus of both professional societies involved.

Pancreas transplantation with enteroanastomosis to native duodenum poses technical challenges--but offers improved endoscopic access for scheduled biopsies and therapeutic interventions

To facilitate endoscopic access for rejection surveillance and stenting of the pancreas, we have abandoned the duodenojejunostomy (DJ) in favor of duodenoduodenostomy (DD) in pancreas transplantation (PTx). From September 2012 to September 2013 we performed 40 PTx with DD; 20 solitary-PTx (S-PTx) and 20 simultaneous pancreas and kidney transplantation (SPK). We compared the outcomes with results from 40 PTx-DJ (10 S-PTx and 30 SPK) from the preceding era. The DD-enteroanastomoses were performed successfully. Endoscopic pancreas biopsies (endoscopic ultrasound examination [EUS]) yielded representative material in half of the cases. One exocrine fistula was treated by endoscopic stenting. PTxs-DD were associated with a higher rate of thrombosis compared to PTx-DJ (23% vs. 5%) and reoperations (48% vs. 30%), as well as inferior graft survival (80% vs. 88%). Time on waiting list, HLA A + B mismatches and reoperations were associated with graft loss. Only recipient age remained an independent predictor of patient death in multivariate analysis. PTx-DD showed a higher rate of thrombosis and inferior results, but facilitated a protocol biopsy program by EUS that was feasible and safe. Given that technical difficulties can be solved, the improved endoscopic access might confer long-term benefits, yet this remains to be proven.

Predictive factors for live birth in cryopreservation single embryo transfer cycles

IVF cryopreservation cycles are known to be less successful than fresh cycles. The objective of this study was to investigate what variables, maternal and embryonic, that independently predict the live birth rate in cryopreservation single embryo transfers (SET). A retrospective analysis was performed on 622 cryopreservation SET originating from 371 consecutive patients performing 410 fresh cycles. Maternal and embryonic variables were analysed using logistic regression. The overall pregnancy and live birth rates were 22 and 16% respectively. Blastomere survival rate, number of previous fresh cycles and IVF as fertilization method compared with intracytoplasmic sperm injection (ICSI), were positive predictors of live birth. Number of embryos thawed to obtain one transfer was negatively associated with pregnancy rate but not with live birth rate. No statistical difference in live birth rate was found whether the couple had performed one, two or three failed cryopreservation cycles previously from the same egg retrieval. Knowledge of certain predictors for live birth contributes to the estimation of prognosis in cryopreservation SET, and is important when deciding whether to perform single or double embryo transfer in cryopreservation cycles. However, despite being independently associated with live birth and pregnancy, the predictive value of identified variables was low.

Preimplantation genetic screening in women of advanced maternal age caused a decrease in clinical pregnancy rate: a randomized controlled trial

BACKGROUND

Advanced maternal age (AMA) is an important parameter that negatively influences the clinical pregnancy rate in IVF, in particular owing to the increased embryo aneuploidy rate. It has thus been suggested that only transferring euploid embryos in this patient group would improve the pregnancy rate. The purpose of this study was to test whether employing preimplantation genetic screening (PGS) in AMA patients would increase the clinical pregnancy rate.

METHODS

We conducted a two-center, randomized controlled trial (RCT) to analyze the outcome of embryo transfers in AMA patients (>or=38 years of age) after PGS using FISH analysis for chromosomes X, Y, 13, 16, 18, 21 and 22. The PGS group was compared with a control group. The primary outcome measure was clinical pregnancy rate after 6-7 weeks of gestation per randomized patient.

RESULTS

The study was terminated early as an interim analysis showed a very low conditional power of superiority for the primary outcome. Of the 320 patients calculated to be included in the study, 56 and 53 patients were randomized into the PGS and control groups, respectively. The clinical pregnancy rate in the PGS group was 8.9% (95% CI, 2.9-19.6%) compared with 24.5% (95% CI, 13.8-38.3%) in the control group, giving a difference of 15.6% (95% CI, 1.8-29.4%, P = 0.039).

CONCLUSIONS

Although the study was terminated early, this RCT study provides evidence against the use of PGS for AMA patients when performing IVF.

TRIAL REGISTRATION NUMBER

ISRCTN38014610.

Association between polymorphisms in the prostate-specific antigen (PSA) promoter and release of PSA

Variations in serum prostate-specific antigen (PSA) have been ascribed to A/G nucleotide polymorphisms located at -158 bp (rs266882) and -4643 bp (rs925013), relative to the transcription start site within the promoter of the PSA gene. PSA is also an androgen receptor target (AR) gene and polymorphisms in AR gene are known to affect AR function. Our objective was to compare the impact of these A/G polymorphisms separately or in combination with AR CAG micro satellite on regulation of PSA secretion into seminal plasma and blood in young men. Leukocyte DNA was extracted from 291 conscripts and genotyping performed with the Sequenom Mass Array System. PSA was measured with an immunofluorometric assay. Linear regression analysis was used to test the association of polymorphism frequencies with serum and seminal plasma levels of PSA. PSA gene polymorphisms at -158 bp or -4643 bp did not alone influence total PSA (tPSA) levels in seminal plasma or in blood. Homozygotes for the A-allele at -158 bp in combination with CAG > 22 had significantly higher serum levels of tPSA than subjects carrying the G-allele (p = 0.01). In conclusion, the PSA gene polymorphisms did not importantly influence the levels of tPSA in seminal plasma or in blood. tPSA in serum was influenced by interactions between PSA promoter variants and AR CAG polymorphism.

Predictors of ongoing implantation in IVF in a good prognosis group of patients

BACKGROUND

The aim of this study was to investigate whether, in a large randomized trial, it is possible to identify specific maternal and/or embryo variables that could independently correlate with ongoing implantation in IVF/ICSI.

METHODS

In a Scandinavian study, 661 women were randomized to elective single embryo transfer or double embryo transfer. Women aged <36 years undergoing their first or second IVF cycle and with at least two good quality embryos were eligible. Only one cycle per subject was included. In the present study, cycles with 0 or 100% ongoing implantation (n = 520) were analysed regarding maternal and embryo variables.

RESULTS

In this selected study group, the ongoing implantation rate was 195/734 (26.6%). In the univariate analysis, first IVF cycle, conventional IVF as fertilization method and 4-cell embryos showed a statistically higher ongoing implantation rate than did second IVF cycle, ICSI and non-4-cell embryos. In the multivariate analysis the same variables correlated independently to ongoing implantation. In addition, ovarian sensitivity correlated independently to ongoing implantation.

CONCLUSION

This information should be used when selecting the number of embryos for transfer with the overall aim to reduce the rate of multiple births while maintaining a satisfactory birth rate.

FISH analysis for chromosomes 13, 16, 18, 21, 22, X and Y in all blastomeres of IVF pre-embryos from 144 randomly selected donated human oocytes and impact on pre-embryo morphology

BACKGROUND

The data are compiled from two multicentre, prospectively randomized studies on the effect of follicular fluid meiosis-activating sterol (FF-MAS) on human oocytes. The donated oocytes were exposed either to test doses of FF-MAS or to control solutions. The data from the control groups are presented with chromosomal status of the embryos correlated to embryo morphology.

METHODS

The study includes 144 randomly selected donated human oocytes. The nucleus from each blastomere was fixed separately and fluorescence in-situ hybridization (FISH) using seven probes (13, 16, 18, 21, 22, X and Y) was performed.

RESULTS

Analysis of 103 pre-embryos containing 479 blastomeres resulted in 424 blastomeres with clear FISH signals. Of these blastomeres, 55% were normal diploid and 45% were abnormal. At a pre-embryonic level, 53% were classified as normal containing >or=50% normal blastomeres while 31% of the pre-embryos were classified as uniformly normal. Abnormality rate was significantly increased in the pre-embryos with unevenly sized blastomeres and with increasing degree of fragmentation at 68 h after fertilization. Applying criteria for good embryo quality significantly increased the rate of chromosomally normal pre-embryos from 53 to 75%.

CONCLUSIONS

The data demonstrate the high degree of genetic heterogeneity in a randomly selected pool of donated pre-embryos from an IVF programme. Further, we found that uniformity of blastomere size, degree of fragmentation and cleavage kinetics reflect the cytogenetic status of the pre-embryo and are therefore important in the selection of pre-embryos.

An alternative to PVP for slowing sperm prior to ICSI

BACKGROUND

There is a growing awareness of potential problems in exposing sperm to polyvinylpyrrolidone (PVP) to slow their motility, a procedure commonly used prior to ICSI. The study presented here evaluates an alternative product for slowing sperm motility, which contains hyaluronate, a substance found naturally in the reproductive tract.

METHODS

Computerized sperm motility analysis was used to compare the motilities of sperm exposed to either a PVP-containing product (ICSI-100), or a hyaluronate-containing product (SpermCatch), or control sperm resuspended in a sperm maintenance medium. A subjective assessment was made of the ease with which sperm could be isolated and be drawn into, and expelled from, an injection pipette after having their tails nicked. Sperm exposed to either ICSI-100 or SpermCatch were used for ICSI. Fertilization rate, zygote development, grading, and outcome of transfer were recorded for the two treatment groups.

RESULTS

The hyaluronate-containing product slowed sperm motility sufficiently for the sperm to be captured in an injection pipette, was easy to draw into and expel from the pipette, prevented sperm sticking to plastic or glassware, and did not affect post-injection zygote development. Clinical pregnancy rates were similar for the two groups.

CONCLUSIONS

This product represents an alternative to PVP for slowing sperm motility prior to ICSI.

Development of a time-resolved fluorescence resonance energy transfer assay (cell TR-FRET) for protein detection on intact cells

An assay named Cell TR-FRET based on time-resolved fluorescence resonance energy transfer, here utilized for detection of receptor proteins on intact cells, is described. In this assay, intact membrane-biotinylated Sf9 cells expressing human interleukin-2Ralpha due to infection with a recombinant baculovirus were prelabeled with a streptavidin-europium (Eu(3+)) chelate, the donor. These prelabeled cells were used in a homogeneous assay by addition of a fluorochrome-labeled anti-hIL-2Ralpha-specific antibody, 7G7B6-Cy5, the acceptor. Binding of 7G7B6-Cy5 to hIL-2Ralpha expressed on the cell surface and europium-labeled streptavidin to surface biotin esters brings the donor and the acceptor in close proximity, allowing transfer of energy from the excited state donor to the acceptor. This energy transfer was specifically inhibited by unlabeled antibody and by free biotin. The described assay constitutes a general method since no specific component of the cell membrane is labeled, thereby allowing a number of binding studies on the cell membrane, including receptor density determinations, to be performed. In addition, due to the rapid fashion in which the Cell TR-FRET assay is accomplished, it can be a valuable method not only for identifying novel membrane-associated proteins, but also for drug screening of large samples in high-throughput format.

Early embryo cleavage is a strong indicator of embryo quality in human IVF

BACKGROUND

In order to decrease multiple birth rates without decreasing birth rates overall, it is important to increase the capability of selecting the most optimal embryos for transfer. It has been shown that human embryos which cleave early, i.e. complete the first mitotic division within 25-27 h post insemination, provide higher pregnancy and implantation rates.

METHODS AND RESULTS

In this prospective study, an evaluation of 10 798 scored embryos showed that early cleavage resulted in a significantly higher proportion of good quality embryos compared with late cleavage (62.5 versus 33.4%, P < 0.0001). When examining both day 2 and day 3 transfers together, early-cleaving embryos (306 transfers) gave rise to significantly higher rates of pregnancy/transfer (40.5 versus 31.3%, P = 0.0049), implantation (28.0 versus 19.5%, P = 0.0001) and birth/ongoing pregnancy (34.3 versus 24.0%, P = 0.0009) than did late-cleaving embryos (521 transfers). A stepwise logistic regression of all data showed that the total number of good quality embryos and female age were independent predictors of both pregnancies and birth. For intracytoplasmic sperm injection (ICSI) embryos, early cleavage was found to be an independent predictor of birth.

CONCLUSIONS

Early embryo cleavage is a strong biological indicator of embryo potential, and may be used as an additional embryo selection factor for ICSI embryos.

Production and partial characterization of mouse monoclonal antibodies recognizing common cytokine receptor gamma chain (gammac) of human, mouse and primate origin

Monoclonal antibodies specific for the common cytokine receptor gamma chain, gammac, were produced using traditional hybridoma technology. Fusion of P3X63-Ag8.653 myeloma cells with splenocytes from Balb/c mice immunized with Spodoptera frugiperda insect cells infected with the recombinant baculovirus VL1392-hIL-2Rgamma resulted in several hybridoma cell clones producing monoclonal gammac-specific antibodies. Four of these antibody-producing clones, IIIC3, IIIE8, IG3 and IF10C5, were further characterized by immunoblotting, flow cytometry and ELISA. Data are presented demonstrating that the generated monoclonal antibodies can identify the extracellular domain of the common cytokine receptor gamma chain of human and mouse origin, and two of the antibodies recognize gammac of primate origin as well.

Acrosome index is not an absolute predictor of the outcome following conventional in vitro fertilization and intracytoplasmic sperm injection

PURPOSE

To investigate if including evaluation of acrosome index (AI) in the semen analysis of teratozoospermic samples could help to predict for which patients intracytoplasmic sperm injection (ICSI) is necessary.

METHODS

The fertilization rate, pregnancy rate, and percentage of good quality embryos were compared after performing conventional in vitro fertilization (IVF) and ICSI, respectively, using sibling oocytes. The role of AI was evaluated by dividing patients into two groups; Group A (AI < 7%) and Group B (AI > or = 7%).

RESULTS

A significant difference in fertilization rate was observed between Group A and B after conventional IVF. In Group A, the fertilization rate, embryo transfer rate, and percentage of good quality embryos were higher after ICSI than after IVF. In Group B, the fertilization and pregnancy rates were numerically but not significantly higher after IVF compared to ICSI.

CONCLUSION

Evaluation of acrosome index will not accurately predict fertilization, although this study shows that a sperm sample with less than 5% normal forms and an AI greater than 7% may achieve a mean fertilization rate > 70% after conventional IVF.

Preimplantation genetic diagnosis (PGD): the Gothenburg experience

BACKGROUND

A program for preimplantation genetic diagnosis of pre-embryos from patients with hereditary disorders was set up in our unit at Sahlgrenska University Hospital in 1994. The majority of the patients were carriers of X-chromosome linked disorders; a few patients were translocation carriers. In this paper we describe our experiences of our first 36 cycles, 30 gender determinations and six analyses of embryos with possible translocations.

METHODS

Conventional hormone replacement treatment with intracytoplasmic sperm injection to fertilize the eggs followed by blastomere biopsy and fluorescent in situ hybridization at the eight cell stage was used for sexing as well as detection of translocations.

RESULTS

Out of the 30 cycles in 13 patients for gender determination, blastomere biopsies could be carried out in 25 cycles. Transfer of normal female embryos (XX) was performed in 18 cycles, resulting in five pregnancies (pregnancy rate 27.8%) and an implantation rate of 20% per transfer. Three girls have been born. Hence the take home baby rate was 16.7% per transfer and 10% per started cycle. Six cycles (three patients) for detection of translocations in embryos were performed. Diagnosis was possible in four cycles. Transfer of normal embryos was carried out in one cycle. No pregnancy was achieved.

CONCLUSION

Successful PGD in its clinical application demands close collaboration between a large group of specialists. Even so, the success rate is considerably lower than after conventional IVF or ICSI procedures. Taking into account the stress caused to the parents facing late interruption of pregnancy following conventional prenatal diagnosis we are convinced that this technique is well worthwhile continuing and refining.

Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation

Uneven blastomere cleavage in human embryos of 'good morphology', i.e. those normally used for transfer, is a phenomenon which has been poorly investigated. The main objective in this study was to probe deeper into the aetiology behind previous findings that embryos with uneven cell cleavage have a lower developmental capacity in comparison with evenly cleaved embryos. Our hypothesis was that uneven cleavage may result in embryos with a higher degree of aneuploidy and/or multinuclear rate, which in turn might help to explain their low implantation rate. In the first part of the study, 378 embryo transfers performed over a 3-year period were analysed retrospectively, where all the transferred embryos in each cycle were of identical morphology score and cleavage stage. In the second part of the study, multicolour fluorescence in-situ hybridization (FISH) analyses on good quality embryos, representing the uneven (n = 11) and even (n = 13) study groups were performed. When comparing day 2 transfers between 4-cell embryos, it was found that unevenly cleaved embryos had significantly lower implantation (23.9 and 36.4%) and pregnancy rates (37.6 and 52.9%) compared with evenly cleaved embryos. A significantly higher degree of aneuploidy (29.4 and 8.5%) and multinuclear rate (21.1 and 2.1%) in blastomeres from uneven embryos was also found. It is concluded that uneven blastomere cleavage has a negative effect on both pregnancy and implantation rates in human IVF, and that this can partly be explained by a higher degree of aneuploidy/multinuclear rate. In the light of the results obtained, a new approach in the current embryo scoring system, placing more emphasis on blastomere size, is recommended.

Ciliary ultrastructure of polyplacophorans (Mollusca, Amphineura, Polyplacophora)

This study is part of a series of papers aiming to investigate the phylogenetic significance of ciliary ultrastructure among molluscs and to test the hypothesis of a relationship between Xenoturbella and the molluscs. The ultrastructure of the ciliary apparatus on the gills of the polyplacophorans Leptochiton asellus and Tonicella rubra was studied. The gill cilia of the two species are similar in shape. The free part of the cilium is long with a slender distal part. There are two ciliary rootlets. One of them is short, broad and placed on the anterior face of the basal body. The other rootlet is conical and has a vertical orientation. Among the mollusca, two ciliary rootlets in the ciliary apparatus of multiciliate ectodermal cells have only been reported from the Chaetodermomorpha and Neomeniomorpha. This character state is likely plesiomorphic for the Mollusca and indicates a basal (nonderived) position of these taxa among the molluscs. No possible synapomorphic character with Xenoturbella bocki was found.

Selection of patients suitable for one-embryo transfer may reduce the rate of multiple births by half without impairment of overall birth rates

The aim of the present study was to identify a subset of patients at high risk of multiple birth after IVF and hence suitable for one-embryo transfer, which undoubtedly would reduce the multiple birth rate. This retrospective study included 2107 IVF cycles in which two embryos were transferred. Factors with possible correlation to multiple birth were studied in a multivariate analysis. The factors included background data (female age, previous pregnancies and births, previous IVF cycles, indication for IVF) and IVF cycle characteristics. The following factors were independently predictive of multiple birth: female age expressed a negative correlation while number of good quality embryos transferred was positively correlated. A subset of patients was identified as being at high risk of multiple birth by including age, cycle number and presence of tubal infertility in a model derived from a logistic regression analysis. The rate of multiple births can be reduced from 26% to 13% of all births if one-embryo transfer is performed in selected cases. The total birth rate will decrease from 29% to 25% but may be completely restored by performing one additional one-embryo freeze transfer in high risk patients who do not achieve a term pregnancy.

The position of the metaphase II spindle cannot be predicted by the location of the first polar body in the human oocyte

When performing intracytoplasmic sperm injection (ICSI) on human oocytes, the injection is traditionally made at the 3 o'clock position, with the first polar body (PB) at the 12 or 6 o'clock position. This has been based on the assumption that the second meiotic metaphase II (MII) spindle lies in close proximity to the first PB. The objective of this study was to document the actual spatial relationship between the first PB and the MII spindle both in in-vivo matured (fresh) human MII oocytes and in oocytes matured in vitro. We found that the MII spindle was, on average, not located directly adjacent to the PB. The in-vivo group (n = 54) showed a mean deviation of the MII spindle from the position of the PB of 41. 7 degrees and the in-vitro group 26.6 degrees (n = 43). The difference between the angle of the two groups was statistically significant (P = 0.005), indicating that the lateral displacement of the first PB is only partly due to the denuding procedure during ICSI, because the in-vitro matured oocytes were denuded before extrusion of the first PB. The majority of the MII spindles in both groups were found in the same hemisphere as the first PB, suggesting that care should be taken to avoid damaging the MII spindle by inserting the ICSI needle in the other half of the oocyte.

Incidence of congenital malformations in children born after ICSI

The aim of this study was to determine the incidence of congenital malformations in a complete cohort of children born after intracytoplasmic sperm injection (ICSI). The medical records were retrieved for 1139 infants, 736 singletons, 200 sets of twins and one set of triplets. The total number of infants with an identified anomaly was 87 (7.6%), 40 of which were minor. The incidence of malformations in children born after ICSI was also compared with all births in Sweden using data from the Swedish Medical Birth Registry and the Registry of Congenital Malformations. For ICSI children, the odds ratio (OR) for having any major or minor malformation was 1.75 [95% confidence interval (CI) 1.19-2.58] after stratification for delivery hospital, year of birth and maternal age. If stratification for singletons/twins was also done, the OR was reduced to 1.19 (95% CI 0.79-1.81). The increased rate of congenital malformations is thus mainly a result of a high rate of multiple births. The only specific malformation which was found to occur in excess in children born after ICSI was hypospadias (relative risk 3.0, exact 95% CI 1. 09-6.50) which may be related to paternal subfertility.

The use of silane-coated silica particles for density gradient centrifugation in in-vitro fertilization

Silane-coated silica particles (PureSperm) were evaluated as an alternative to Percoll for gradient separation of spermatozoa, for use in assisted reproduction. Recovery of motile and morphologically normal spermatozoa after using a four-layer Percoll and a two- and four-layer PureSperm gradient respectively was recorded. In-vitro fertilization (IVF) results after using PureSperm for the sperm preparation were also evaluated. No difference in sperm recovery or sperm motility was found when comparing the use of Percoll and the four-layer gradient of PureSperm. When using a two-layer PureSperm gradient, motility was significantly decreased (P < 0.05) compared to Percoll. Normal sperm morphology increased from 8-17.2% after using Percoll and to 12.7% and 11.4% after using a four-layer and a two-layer PureSperm gradient respectively. All gradient preparations showed a significant decrease in the teratozoospermia index compared to the ejaculate (P < 0.01). No significant differences in IVF results regarding fertilization and pregnancy rates were found when PureSperm or the swim-up technique were used for the sperm preparation. PureSperm seems to be an acceptable alternative to Percoll but although the percentage of sperm recovery was higher after PureSperm we still recommend the swim-up technique to be the first choice, as a higher percentage of progressive motile spermatozoa is obtained without using other chemicals than IVF culture medium.

Diagnostic epididymal and testicular sperm recovery and genetic aspects in azoospermic men

Various procedures for sperm recovery in azoospermic men have been described, from open testicular biopsy to simple needle aspiration from the epididymis and the testis. Fifty-one obstructive and 86 non-obstructive azoospermic men were treated to compare the recovery of spermatozoa obtained by percutaneous aspiration from the epididymis (PESA) and aspiration/extraction from the testis (TESA, TESE) with histopathology. If TESA failed, the work up proceeded with TESE. All patients were karyotyped. Spermatozoa were recovered by PESA or TESA in all obstructive men (51/51 patients). In 22 out of 86 patients with non-obstructive azoospermia, testicular spermatozoa could be successfully recovered by TESA. In five additional patients TESE was successful in recovering spermatozoa where TESA had failed. In 43 patients, neither TESA nor TESE was successful. Sixteen patients chose not to proceed with TESE. Seven out of 86 patients had an abnormal karyotype in the non-obstructive group (8%), none in the obstructive group. In the non-obstructive patient group testicular histopathology showed hypospermatogenesis, incomplete maturation arrest and germ cell aplasia with focal spermatogenesis in cases where spermatozoa were recovered and complete germ cell aplasia, complete maturation arrest and fibrosis in cases where no spermatozoa were found. Spermatozoa were recovered by PESA or TESA from all patients with obstructive azoospermia and from approximately 40% of patients with non-obstructive azoospermia by TESA or TESE. Retrieval of viable spermatozoa in the infertility work-up was highly predictable for sperm recovery in subsequent ICSI cycles. TESA performed under local anaesthesia seems almost as effective as more invasive procedures in recovering testicular spermatozoa, both in obstructive and non-obstructive azoospermic men.

Sperm retrieval and fertilization in repeated percutaneous epididymal sperm aspiration

Percutaneous epididymal sperm aspiration (PESA) for retrieval of spermatozoa for intracytoplasmic sperm injection (ICSI) is a new simplified technique in the treatment of men with obstructive azoospermia. There has been a fear that the PESA procedure, being blind, could cause damage to the epididymal duct system and make it impossible to retrieve spermatozoa if a repeated procedure is required. We report here on repeated PESA procedures from the same unilateral epididymis. Twenty-seven men with obstructive azoospermia were investigated retrospectively regarding sufficiency of the number of motile spermatozoa for ICSI, fertilization rate (FR) and possibility of collecting spermatozoa for cryopreservation in repeated PESA procedures. Sufficient motile spermatozoa for ICSI were found in a similar proportion of men at the first two attempts: 91 and 89% respectively. Fertilization rate and the possibility of collecting spermatozoa for cryopreservation were also similar at the first two PESA procedures: 62 versus 67% and 33 versus 33% respectively. At the third procedure, motile spermatozoa for ICSI were retrieved in 86% (6/7), FR was 47% and spermatozoa were cryopreserved in one case. Two men underwent a fourth PESA. In both cases, a sufficient number of motile spermatozoa for ICSI was found and FR was 62%. This study shows that in men with obstructive azoospermia, PESA can be repeated on the same unilateral epididymis up to three times, with good opportunity of retrieving sufficient motile spermatozoa for ICSI.