Effect of alfentanil dosage during oocyte retrieval on fertilization and embryo quality

OBJECTIVE

A possible negative effect of pain-relieving analgesics used during oocyte retrieval on fertilization and embryo development has been discussed. This study examines whether alfentanil dosage adversely affects fertilization and/or embryo quality.

STUDY DESIGN

In a retrospective observational study the effect of different doses of alfentanil on two primary endpoints, fertilization rate and good quality embryo (GQE) rate, were compared in 663 women.

RESULTS

In group A (<or=0.5mg alfentanil) and group B (>0.5mg alfentanil) mean fertilization rate was 0.6+/-0.3 versus 0.6+/-0.2 (P=0.678, adjusted P=0.937, 95% CI for the difference -0.041; 0.044) and mean GQE rate was 0.6+/-0.3 versus 0.5+/-0.3 (P=0.207, adjusted P=0.179, 95% CI for the difference -0.015; 0.078), respectively. A paired comparison of 65 women who underwent repeated IVF cycles found that, compared with <or=0.5mg alfentanil, doses of >0.5mg alfentanil had no adverse effects on fertilization rate (mean difference 0.05+/-0.3, P=0.231, 95% CI -0.02; 0.12) or GQE rate (mean difference -0.02+/-0.4, P=0.970, 95% CI -0.12; 0.09).

CONCLUSION

The amount of alfentanil is not associated with adverse effects on fertilization rate, embryo development, or clinical pregnancy rate, which is reassuring and indicates that women can be offered adequate pain relief.

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.

Influence of ovarian stimulation with HP-hMG or recombinant FSH on embryo quality parameters in patients undergoing IVF

BACKGROUND

There are limited data on the impact of different gonadotrophin preparations on embryo quality.

METHODS

This evaluation was part of a randomized, assessor-blind, multinational trial, conducted in 731 women undergoing IVF after stimulation with highly purified human menopausal gonadotropin (HP-hMG; MENOPUR) (n = 363) or recombinant FSH (rFSH; GONAL-F) (n = 368). Ongoing pregnancy was the primary end-point [HP-hMG 27% and rFSH 22%; odds ratio (OR) (95% confidence interval, CI) 1.25 (0.89-1.75)]. All 7535 oocytes retrieved were evaluated daily until day 3 (embryo transfer) in a blinded manner both by local site embryologists and a central panel of three embryologists.

RESULTS

The proportion of top-quality embryos per oocyte retrieved was higher with HP-hMG (11.3%) compared with rFSH (9.0%) (P = 0.044) in the local assessment, but comparable in the central assessment (9.5 and 8.0%, respectively). Significant differences in favour of HP-hMG were observed for number of blastomeres and degree of fragmentation, while uniformity of blastomere sizes, localization of fragments, frequency of multinucleation and homogeneous cytoplasm were comparable between HP-hMG and rFSH. The live birth, ongoing pregnancy and ongoing implantation rates for top-quality embryos were higher with HP-hMG than rFSH [48 versus 32% (P = 0.038), 48 versus 32% (P = 0.038), 41 versus 27% (P = 0.032)]. Both the proportion of embryos with at least 50% surviving blastomeres after cryopreservation and embryos resuming mitosis were more frequent with HP-hMG compared with rFSH.

CONCLUSIONS

Composition of gonadotrophin preparations used during ovarian stimulation has an impact on some embryo quality parameters. The capacity to implant of the top-quality embryos derived from stimulation with HP-hMG appears to be improved, although the mechanism needs to be elucidated.

Effect of rescuing donated immature human oocytes derived after FSH/hCG stimulation following in vitro culture with or without Follicular Fluid Meiosis Activating Sterol (FF-MAS)--an embryo chromosomal and morphological analysis

PURPOSE

Studies in mice and humans have shown that Follicular Fluid - Meiosis Activating Sterol (FF-MAS) induces meiotic maturation of immature oocytes in vitro. A multicenter, prospectively randomised study evaluated chromosomal status of embryos from FSH/hCG primed human immature oocytes, cultured with or without FF-MAS.

METHODS

Denuded immature oocytes (n=365) were randomly allocated into inert control, FF-MAS 5 microM or 20 microM. Seventy +/-2 hours after ICSI on matured oocytes, all cleaved embryos were fixed for fluorescence in situ hybridisation analysis.

RESULTS

Only 15% of oocytes resulted in cleaved embryos. GV oocytes matured at significantly lower rates (14% and 7%) in the two FF-MAS groups compared to the inert control group (47%). High rates of chromosomal abnormalities were found in all groups.

CONCLUSION

Immature oocytes showed poor development with high rates of embryo chromosomal abnormalities. Exposure to FF-MAS in the concentrations, duration and/or formulation used in this study did not improve the results.

Cumulative impact of adding frozen–thawed cycles to single versus double fresh embryo transfers

Randomized control trials have shown that single embryo transfer (SET) results in lower live birth rates than double embryo transfer (DET), while observational, retrospective studies find no decrease in overall live birth rate when using a SET policy. The cumulative (fresh transfer followed by frozen - thawed transfers of embryos from the same stimulated cycle) live birth rate after the first and the second stimulated cycle of SET and DET respectively has been analysed. All couples who received their first fresh embryo transfer at Sahlgrenska University Hospital during 2003 and 2004 were included (n = 689). The live birth rates after DET versus SET in the first and second fresh cycles were 29.7 (47/158) versus 23.9% (127/531) and 30.8 (41/133) versus 22.0% (45/205). The cumulative live birth rate per patient after the addition of frozen-thawed embryo transfers were similar: 33.5 (53/158) and 34.8% (185/531) for DET and SET respectively after the first cycle and 32.3 (43/133) versus 32.2% (66/205) after the second cycle. A logistic regression analysis showed no significant correlation for SET or DET with cumulative live birth. Thus, cumulative live birth rates are similar after SET and DET in a routine IVF programme with a majority of SET transfers, although a higher number of frozen-thawed cycles were needed in the SET group.

Derivation of a xeno-free human embryonic stem cell line

Elimination of all animal material during both the derivation and long-term culture of human embryonic stem cells (hESCs) is necessary prior to future application of hESCs in clinical cell therapy. The potential consequences of transplanting xeno-contaminated hESCs into patients, such as an increased risk of graft rejection [Stem Cells 2006; 24:221-229] and the potential transfer of nonhuman pathogens, make existing hESC lines unsuitable for clinical applications. To avoid xeno-contamination during derivation and culture of hESCs, we first developed a xeno-free medium supplemented with human serum, which supports long-term (>50 passages) culture of hESCs in an undifferentiated state. To enable derivation of new xeno-free hESCs, we also established xeno-free human foreskin fibroblast feeders and replaced immunosurgery, which involves the use of guinea pig complement, with a modified animal-product-free derivation procedure. Here, we report the establishment and characterization (>20 passages) of a xeno-free pluripotent diploid normal hESC line, SA611.

The interface between assisted reproductive technologies and genetics: technical, social, ethical and legal issues

The interface between assisted reproductive technologies (ART) and genetics comprises several sensitive and important issues that affect infertile couples, families with severe genetic diseases, potential children, professionals in ART and genetics, health care, researchers and the society in general. Genetic causes have a considerable involvement in infertility. Genetic conditions may also be transmitted to the offspring and hence create transgenerational infertility or other serious health problems. Several studies also suggest a slightly elevated risk of birth defects in children born following ART. Preimplantation genetic diagnosis (PGD) has become widely practiced throughout the world for various medical indications, but its limits are being debated. The attitudes towards ART and PGD vary substantially within Europe. The purpose of the present paper was to outline a framework for development of guidelines to be issued jointly by European Society of Human Genetics and European Society of Human Reproduction and Embryology for the interface between genetics and ART. Technical, social, ethical and legal issues of ART and genetics will be reviewed.

Interobserver agreement and intraobserver reproducibility of embryo quality assessments

BACKGROUND

The objective of this investigation was to determine the inter- and intraobserver agreement when assessing embryo quality.

METHODS

This investigation included 4002 cleaved embryos from 7535 oocytes retrieved in 688 patients undergoing IVF cycles in a multicentre trial. Embryos were evaluated locally at the inverted microscope at 28, 44 and 68 h (+/-1 h) post-insemination. Digital images of the embryos were assessed centrally by three blinded embryologists. To assess reproducibility, 215 randomly selected cleaved embryos from 33 patients were re-evaluated by the three central embryologists.

RESULTS

The interobserver agreement among the central embryologists (using the same method of evaluation; 2D images) was good for classification of top-quality embryos (kappa 0.71-0.73), excellent for classification of normally developed embryos (kappa 0.83-0.86) and good-excellent for classification of transferable embryos (kappa 0.78-0.82). The interobserver agreement between local and consolidated central assessment (different methods of evaluation, inverted microscopy versus 2D images) was good for all three embryo classifications (kappa 0.64-0.79). The intraobserver reproducibility for all three overall embryo classifications was excellent for the consolidated central assessment (kappa 0.80-0.91).

CONCLUSION

Embryo quality can be determined with a good degree of interobserver agreement independently of the method of evaluation. Embryologists classify embryos with excellent intraobserver reproducibility.

Chromosomal integrity maintained in five human embryonic stem cell lines after prolonged in vitro culture

There have been recent reports of human embryonic stem cell (hESC) lines developing chromosomal aberrations after long-term culture, indicating an unstable genomic status due to the in vitro milieu. This raises concern, since it would limit their use in therapeutics. In this study the chromosomal status of five well-characterized hESC lines, SA002, SA002.5, AS034.1.1, SA121 and SA461, was monitored during long-term in vitro culture. The criteria of defined hESCs were met by all of the five hESC lines (four diploid and one trisomic for chromosome 13). The genomes were screened for chromosomal aberrations and rearrangements using comparative genomic hybridization (CGH), interphase fluorescence in situ hybridization (FISH) and traditional karyotyping on several occasions while in culture. The genomic integrity was shown to be maintained after repeated freeze-thaw procedures and continuous culture in vitro for up to 22 months (148 passages). We discuss the most common de novo chromosomal aberrations reported in hESCs, as well as their possible origin.

Choosing fertilization method by analyzing sperm morphology or by performing swim-up preparation

BACKGROUND

Evaluation of sperm morphology has been used as a screening method for choosing between intracytoplasmic sperm injection (ICSI) and conventional in vitro fertilization (IVF). However, sperm morphology analysis is a time-consuming and often subjective scoring method, and may lead to an unnecessarily large proportion of invasive and costly ICSI treatments. The aim of this study was to evaluate if the yield after swim-up preparation could be of advantage over sperm morphology evaluation for choosing fertilization method.

MATERIAL AND METHODS

In the first part of the study 53 split cycles with less than 5% normal forms in the ejaculate were retrospectively evaluated. Part 2 is a prospective evaluation including 357 cycles where the number of sperm available after a standardized swim-up procedure was used for choosing fertilization method. In all cycles where < or = 1 million sperm were obtained after swim-up, conventional IVF was performed.

RESULTS

In the first part no statistically significant difference in fertilization rates was found for IVF and ICSI respectively (59.2% versus 64.7%). Four IVF cycles ended up in total fertilization failure (TFF) while in no ICSI cycle was TFF obtained. In the second part 8.9% TFF was obtained in the poor sperm morphology group compared to 1.3% in the good morphology group. These TFF corresponded to 1% of all our treatment cycles.

CONCLUSION

The present strategy reduced ICSI treatments by 10%, thereby reducing the cost and workload. It can be discussed if an increase of TFF in absolute number of eight is balanced by a reduced workload of 100 ICSI treatments.

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.

Chromosomal abnormality rate in human pre-embryos derived from in vitro fertilization cycles cultured in the presence of Follicular-Fluid Meiosis Activating Sterol (FF-MAS)

BACKGROUND

The objective of the study was to investigate the effect of Follicular-Fluid Meiosis Activating Sterol (FF-MAS) when added to the culture media on the incidence of chromosomal abnormalities and pre-embryo development in human pre-embryos.

METHODS

243 women undergoing IVF/ICSI treatment donated 353 oocytes in a multicentre, prospective, randomized, double blind, four-arm, controlled trial performed at Danish and Swedish public and private IVF centers. Metaphase II oocytes were randomly assigned to: FF-MAS 5 microM, FF-MAS 20 microM, ethanol 0.2% (vehicle control) or water for injection (inert control). The exposure regimen of FF-MAS to the human oocytes was 4 h prior to fertilization by ICSI and 20 h exposure post ICSI. The primary endpoint was the incidence of numerical chromosomal abnormalities. Secondary endpoints were cleavage rate and pre-embryo quality.

RESULT

On the pre-embryo level, no significant differences in chromosomal abnormality rate were observed among the four groups. However, the percentage of uniformly normal pre-embryos was significantly lower in the pooled FF-MAS group (5 microM: 12% and 20 microM: 17%) than in the pooled control group (inert control 32% and vehicle control 42%). A high level of mosaicism (41-60%) was found in all groups. At the blastomere level, the percentage of blastomeres categorized as normal was significantly lower in the FF-MAS 5 microM group (41%) and the FF-MAS 20 microM (29%) group versus the inert (52%) and the vehicle (61%) groups. Significantly reduced cleavage and good quality pre-embryo rates were found in both FF-MAS groups.

CONCLUSION

FF-MAS increased the rate of aneuploidy and had detrimental effects on cleavage and pre-embryo development, when exposed both before and after fertilization.

A randomized, double-blind, controlled trial of the effect of adding follicular fluid meiosis activating sterol in an ethanol formulation to donated human cumulus-enclosed oocytes before fertilization

OBJECTIVE

To evaluate the effect of follicular fluid meiosis activating sterol (FF-MAS) in a 0.2% ethanol formulation on chromosomal status and development of preembryos.

DESIGN

Multicenter, prospective, randomized, double-blind, five parallel group, controlled trial.

SETTING

Public and private IVF-clinics in Denmark and Sweden.

PATIENT(S)

Two hundred ten women undergoing IVF treatment donated 310 oocytes.

INTERVENTIONS(S)

FSH/hCG primed cumulus-enclosed oocytes randomized to 4 hours exposure of medium with 0.1, 1, or 10 microM FF-MAS dissolved in 0.2% ethanol, medium with ethanol 0.2%, or medium with water for injection (control) before insemination.

MAIN OUTCOME MEASURE(S)

Primary: incidence of human preembryos with chromosomal abnormalities. Secondary: fertilization rate, cleavage rate, and preembryo quality after 68 hours of culture.

RESULT(S)

At the preembryo level, no significant differences in chromosomal abnormality rate were found among any of the groups. At the blastomere level, a significant increased abnormality rate was observed in the ethanol group and the combined FF-MAS groups compared with the control group. No significant differences in fertilization rate, cleavage rate, or preembryo quality were observed among any of the groups and the control group except for a significant reduction in the number of embryos with >or=2 cells at 26 hours in the ethanol group.

CONCLUSION(S)

No negative effect of FF-MAS was observed. However, addition of ethanol 0.2% to standard IVF-medium with or without FF-MAS for culturing cumulus-enclosed oocytes for 4 hours before insemination increased the chromosomal abnormality rate at the blastomere level. Further studies of FF-MAS in a nonethanol formulation are under way.

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.