Preimplantation genetic screening (PGS) has increasingly been used in the past decade. Here we present a systematic review and meta-analysis of RCTs on the effect of PGS on the probability of live ...birth after IVF.
PubMed and trial registers were searched for RCTs on PGS. Trials were assessed following predetermined quality criteria. The primary outcome was live birth rate per woman, secondary outcomes were ongoing pregnancy rate, miscarriage rate, multiple pregnancy rate and pregnancy outcome.
Nine RCTs comparing IVF with and without PGS were included in our meta-analysis. Fluorescence in situ hybridization was used in all trials and cleavage stage biopsy was used in all but one trial. PGS significantly lowered live birth rate after IVF for women of advanced maternal age (risk difference: -0.08; 95% confidence interval: -0. 13 to -0.03). For a live birth rate of 26% after IVF without PGS, the rate would be between 13 and 23% using PGS. Trials where PGS was offered to women with a good prognosis and to women with repeated implantation failure suggested similar outcomes.
There is no evidence of a beneficial effect of PGS as currently applied on the live birth rate after IVF. On the contrary, for women of advanced maternal age PGS significantly lowers the live birth rate. Technical drawbacks and chromosomal mosaicism underlie this inefficacy of PGS. New approaches in the application of PGS should be evaluated carefully before their introduction into clinical practice.
BACKGROUND Various models have been developed for the prediction of pregnancy after in vitro fertilization (IVF). These models differ from one another in the predictors they include. We performed a ...systematic review and meta-analysis to identify the most relevant predictors for success in IVF. METHODS We systematically searched MEDLINE and EMBASE for studies evaluating IVF/ICSI outcome. Studies were included if they reported an unconditional odds ratio (OR) or whenever one could be calculated for one or more of the following factors: age, type of infertility, indication, duration of infertility, basal FSH, number of oocytes, fertilization method, number of embryos transferred and embryo quality. RESULTS Fourteen studies were identified. A summary OR could be calculated for five factors. We found negative associations between pregnancy and female age OR: 0.95, 95% confidence interval (CI): 0.94–0.96, duration of subfertility (OR: 0.99, 95% CI: 0.98–1.00) and basal FSH (OR: 0.94, 95% CI: 0.88–1.00). We found a positive association with number of oocytes (OR 1.04, 95% CI: 1.02–1.07). Better embryo quality was associated with higher pregnancy chances. No significant association was found for the type of infertility and fertilization method. A summary OR for IVF indication and number of embryos transferred could not be calculated, because studies reporting on these used different reference categories. CONCLUSIONS Female age, duration of subfertility, bFSH and number of oocytes, all reflecting ovarian function, are predictors of pregnancy after IVF. Better quality studies are necessary, especially studies that focus on embryo factors that are predictive of success in IVF.
Abstract
STUDY QUESTION
Can the organ culture method be applied to both fresh and cryopreserved human (pre)pubertal testicular tissue as a strategy for in vitro spermatogenesis?
SUMMARY ANSWER
...Although induction of spermatogenesis was not achieved in vitro, testicular architecture, endocrine function and spermatogonial proliferation were maintained in both fresh and cryopreserved testicular tissues.
WHAT IS KNOWN ALREADY
Cryopreservation of a testicular biopsy is increasingly offered as a fertility preservation strategy for prepubertal cancer patients. One of the proposed experimental approaches to restore fertility is the organ culture method, which, in the mouse model, successfully allows for in vitro development of spermatozoa from testicular biopsies. However, complete spermatogenesis from human prepubertal testicular tissue in such an organ culture system has not been demonstrated.
STUDY DESIGN, SIZE, DURATION
Testicular tissue was collected from nine (pre)pubertal boys diagnosed with cancer (ranging from 6 to 14 years of age) admitted for fertility preservation before treatment. Testicular biopsies were either immediately processed for culture or first cryopreserved, using a controlled slow freezing protocol, and thawed before culture. Organ culture of testicular fragments was performed in two different media for a maximum period of 5 weeks, targeting early cellular events (viability, meiosis and somatic differentiation) in vitro.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Fresh and cryopreserved-thawed testis fragments (1–2 mm3) were cultured at a gas–liquid interphase (34°C, 5% CO2) in Minimum Essential Medium alpha + 10% knock-out serum replacement medium containing 10−7 M melatonin and 10−6 M retinoic acid, with or without 3 IU/L FSH/LH supplementation. The effect of culture conditions on testicular fragments was weekly assessed by histological evaluation of germ cell development and immunohistochemical identification of spermatogonia (using MAGEA4), proliferative status of spermatogonia and Sertoli cells (using proliferating cell nuclear antigen PCNA), intratubular cell apoptosis (by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) and Sertoli cells maturation (using Anti-Müllerian Hormone AMH versus Androgen Receptor AR). Additionally, Leydig cells’ functionality was determined by measuring testosterone concentration in the culture media supernatants.
MAIN RESULTS AND THE ROLE OF CHANCE
Neither fresh nor cryopreserved human (pre)pubertal testicular fragments were able to initiate spermatogenesis in our organ culture system. Nonetheless, our data suggest that fresh and cryopreserved testicular fragments have comparable functionality in the described organ culture conditions, as reflected by the absence of significant differences in any of the weekly evaluated functional parameters. Additionally, no significant differences were found between the two tested media when culturing fresh and cryopreserved human testicular fragments. Although spermatogonia survived and remained proliferative in all culture conditions, a significant reduction of the spermatogonial population (P ≤ 0.001) was observed over the culture period, justified by a combined reduction of proliferation activity (P ≤ 0.001) and increased intratubular cell apoptosis (P ≤ 0.001). We observed a transient increase in Sertoli cell proliferative activity, loss of AMH expression (P ≤ 0.001) but no induction of AR expression. Leydig cell endocrine function was successfully stimulated in vitro as indicated by increased testosterone production in all conditions throughout the entire culture period (P ≤ 0.02).
LARGE SCALE DATA
N/A
LIMITATIONS, REASONS FOR CAUTION
Although not noticeable in this study, we cannot exclude that if an optimized culture method ensuring complete spermatogenesis in human testicular fragments is established, differences in functional or spermatogenic efficiency between fresh and cryopreserved tissue might be found.
WIDER IMPLICATIONS OF THE FINDINGS
The current inability to initiate spermatogenesis in vitro from cryopreserved human testicular fragments should be included in the counselling of patients who are offered testicular tissue cryopreservation to preserve fertility.
STUDY FUNDING/COMPETING INTEREST(S)
This project was funded by EU-FP7-PEOPLE-2013-ITN 603568 `Growsperm’. None of the authors have competing interests.
TRIAL REGISTRATION NUMBER
Not applicable.
Abstract
STUDY QUESTION
Is IVF with frozen-thawed blastocyst transfer (freeze-all strategy) more effective than IVF with fresh and frozen-thawed blastocyst transfer (conventional strategy)?
SUMMARY ...ANSWER
The freeze-all strategy was inferior to the conventional strategy in terms of cumulative ongoing pregnancy rate per woman.
WHAT IS KNOWN ALREADY
IVF without transfer of fresh embryos, thus with frozen-thawed embryo transfer only (freeze-all strategy), is increasingly being used in clinical practice because of a presumed benefit. It is still unknown whether this new IVF strategy increases IVF efficacy.
STUDY DESIGN, SIZE, DURATION
A single-centre, open label, two arm, parallel group, randomised controlled superiority trial was conducted. The trial was conducted between January 2013 and July 2015 in the Netherlands. The intervention was one IVF cycle with frozen-thawed blastocyst transfer(s) versus one IVF cycle with fresh and frozen-thawed blastocyst transfer(s). The primary outcome was cumulative ongoing pregnancy resulting from one IVF cycle within 12 months after randomisation. Couples were allocated in a 1:1 ratio to the freeze-all strategy or the conventional strategy with an online randomisation programme just before the start of down-regulation.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Participants were subfertile couples with any indication for IVF undergoing their first IVF cycle, with a female age between 18 and 43 years. Differences in cumulative ongoing pregnancy rates were expressed as relative risks (RR) with 95% CI. All outcomes were analysed following the intention-to-treat principle.
MAIN RESULTS AND THE ROLE OF CHANCE
Two-hundred-and-five couples were randomly assigned to the freeze-all strategy (n = 102) or to the conventional strategy (n = 102). The cumulative ongoing pregnancy rate per woman was significantly lower in women allocated to the freeze-all strategy (19/102 (19%)) compared to women allocated to the conventional strategy (32/102 (31%); RR 0.59; 95% CI 0.36–0.98).
LIMITATIONS, REASONS FOR CAUTION
As this was a single-centre study, we were unable to study differences in study protocols and clinic performance. This, and the limited sample size, should make one cautious in using the results as the basis for definitive policy. All patients undergoing IVF, including those with a poor prognosis, were included; therefore, the outcome could differ in women with a good prognosis of IVF treatment success.
WIDER IMPLICATIONS OF THE FINDINGS
Our results indicate that there might be no benefit of a freeze-all strategy in terms of cumulative ongoing pregnancy rates. The efficacy of the freeze-all strategy in subgroups of patients, different stages of embryo development, and different freezing protocols needs to be further established and balanced against potential benefits and harms for mothers and children.
STUDY FUNDING/COMPETING INTEREST(S)
The Netherlands Organisation for Health Research and Development (ZonMW grant 171101007). S.M., F.M. and M.v.W. stated they are authors of the Cochrane review ‘Fresh versus frozen embryo transfers in assisted reproduction’.
TRIAL REGISTRATION NUMBER
Dutch Trial Register, NTR3187
TRIAL REGISTRATION DATE
9 December 2011
DATE OF FIRST PATIENT’S ENROLMENT
8 January 2013
BACKGROUND
Several randomized controlled trials have not shown a benefit from preimplantation genetic screening (PGS) biopsy of cleavage-stage embryos and assessment of up to 10 chromosomes for ...aneuploidy. Therefore, a proof-of-principle study was planned to determine the reliability of alternative form of PGS, i.e. PGS by polar body (PB) biopsy, with whole genome amplification and microarray-based comparative genomic hybridization (array CGH) analysis.
METHODS
In two centres, all mature metaphase II oocytes from patients who consented to the study were fertilized by ICSI. The first and second PBs (PB1and PB2) were biopsied and analysed separately for chromosome copy number by array CGH. If either or both of the PBs were found to be aneuploid, the corresponding zygote was then also processed by array CGH for concordance analysis.
RESULTS
Both PBs were biopsied from a total of 226 zygotes from 42 cycles (average 5.5 per cycle; range 1–15) in 41 couples with an average maternal age of 40.0 years. Of these, the ploidy status of the zygote could be predicted in 195 (86%): 55 were euploid (28%) and 140 were aneuploid (72%). With only one exception, there was at least one predicted aneuploid zygote in each cycle and in 19 out of 42 cycles (45%), all zygotes were predicted to be aneuploid. Fresh embryos were transferred in the remaining 23 cycles (55%), and one frozen transfer was done. Eight patients had a clinical pregnancy of which seven were evolutive (ongoing pregnancy rates: 17% per cycle and 30% per transfer). The ploidy status of 156 zygotes was successfully analysed by array CGH: 38 (24%) were euploid and 118 (76%) were aneuploid. In 138 cases complete information was available on both PBs and the corresponding zygotes. In 130 (94%), the ploidy status of the zygote was concordant with the ploidy status of the PBs and in 8 (6%), the results were discordant.
CONCLUSIONS
This proof-of-principle study indicates that the ploidy of the zygote can be predicted with acceptable accuracy by array CGH analysis of both PBs.
Abstract
STUDY QUESTION
Do men and women beginning to attend a fertility clinic prefer genetic over non-genetic parenthood?
SUMMARY ANSWER
Nearly, all infertile men and women prefer genetic ...parenthood.
WHAT IS KNOWN ALREADY
Clinicians assume that all infertile couples prefer genetic parenthood over non-genetic parenthood and, therefore, consider treatments with donor gametes an option of last resort. Previous studies of the desire for parenthood identified 30 motivations for genetic parenthood, and 51 motivations for which having a genetically related child is not strictly necessary but might be deemed required. The exact strength of the preference of infertile men and women for genetic parenthood remains unclear, as does the importance of the various motivations.
STUDY DESIGN, SIZE, DURATION
A questionnaire was developed based on a literature review. It was assessed by professionals and pilot tested among patients. The coded paper–pencil questionnaire was disseminated among both partners of 201 heterosexual infertile couples after their first consultation at one of two Belgian fertility clinics between October 2015 and May 2016.
PARTICIPANTS/MATERIALS, SETTING, METHODS
The survey addressed: (i) the preference for genetic parenthood for themselves and for their partner, (ii) the importance of 30 motivations for genetic parenthood and (iii) the importance of 51 other motivations for parenthood and whether these motivations require being the genetic parent of their child to be fulfilled. To simplify presentation of the results, all 81 motivations were grouped into reliable categories of motivations using psychometric analyses.
MAIN RESULTS AND THE ROLE OF CHANCE
The survey was completed by 104 women and 91 men (response rate: 49%). Almost all respondents (98%) favored genetic over non-genetic parenthood for both their partner and themselves. One-third of the respondents stated they only wanted to parent their own genetically related child. Achieving genetic parenthood for their partner was considered significantly more important than achieving genetic parenthood for themselves. Within couples, men had a stronger preference for genetic parenthood (P = 0.004), but this was not significant after correction for educational level, which was significantly associated with the preference of both men and women. The 30 motivations for becoming a genetic parent clustered into 11 categories of which ‘to experience a natural process’ was deemed most important. The 51 motivations for becoming a parent for which having a genetically related child is not strictly necessary clustered into 14 categories of which ‘to contribute to a child's well-being’ and ‘to experience the love of a child’ were most important. Respondents deemed they would need to be the genetic parent of their child to fulfill nearly all their motivations for parenthood.
LIMITATIONS REASONS FOR CAUTION
We included couples that visited the fertility clinic for the first time, and the preference for genetic parenthood might change throughout a fertility treatment trajectory. Moreover, what prospective parents expect to be important for their future well-being might not really define parents’ well-being.
WIDER IMPLICATIONS OF THE FINDINGS
The presumed preference of couples for genetic parenthood was confirmed. Resistance against using donor gametes is more likely among lower educated individuals. Researching whether non-genetic parents actually feel they cannot fulfill the 51 motivations for parenthood, could be a basis for developing patient information.
STUDY FUNDING/COMPETING INTEREST(S)
Funded by the Parkes Foundation, the University of Amsterdam and the Leuven University Hospital. No conflict of interest.
What is the acceptability of using stem cell-based fertility treatments (SCFT) for different indications according to gynaecologists and the general public?
The majority of gynaecologists and the ...general public accept SCFT for the indications female or male infertility in young heterosexual couples, and female infertility in single women and same-sex couples.
SCFT could result in genetic parenthood for intended parents with indications that cannot be treated using currently available methods, such as being in a same-sex relationship or female post-menopausal age. It is unclear whether the acceptability of SCFT differs between indications for treatment and whether gynaecologists and the general public differ in their assessments.
In November 2015, a cross-sectional survey was disseminated among 179 gynaecologists and a panel of 1250 respondents comprising a representative sample of the Dutch general public.
The potential indications for future SCFT to achieve genetic parenthood were identified by literature review. A questionnaire was developed, reviewed by experts from different disciplines and tested among the general public. The questionnaire asked whether treating eight groups of intended parents with SCFT was acceptable or not. Regression analysis examined whether demographic characteristics influenced choices and whether the general public and gynaecologists differed in opinion.
A total of 82 (46%) gynaecologists and 772 (62%) members of the general public completed the survey. The acceptability of using SCFT varied according to both gynaecologists and the general public between the eight groups of intended parents (P < 0.001). The majority of the Dutch general public accepts SCFT for six out of eight possible indications, namely female infertility in young heterosexual couples (94%), male infertility in young heterosexual couples (94%), unexplained infertility in young heterosexual couples (83%), female infertility in single women (69%), lesbian couples (68%) and gay couples (62%). The majority of gynaecologists also found treating these groups acceptable, except for the indication of unexplained infertility, which was only accepted by a minority of gynaecologists (43%). A minority of both the general public and gynaecologists accepted SCFT for fertile women who want a child that is genetically only her own (27 and 6%, respectively) and for female infertility in heterosexual couples in which the woman is over 50 years of age (17% and 26%, respectively). Attaching low importance to religion, having progressive political preferences, not having a university degree, having experienced infertility, being a woman, being older and not being of European ethnicity were positively associated with considering using SCFT acceptable for one or multiple indications.
N/A.
The generalizability of our findings to future decades or other countries might be limited as opinions about novel technologies change over time and might vary across cultures. Support among gynaecologists and the general public is interesting but not proof of ethical acceptability.
Once proven safe and effective, fear of limited acceptability by the general public is unwarranted, and thus should not stop gynaecologists from offering SCFT to single infertile women and same-sex couples in addition to young infertile heterosexual couples.
Funded by the Young Academy of the Royal Netherlands Academy of Arts and Sciences and the Universities of Amsterdam and Leuven. No conflict of interest to declare.
Abstract
STUDY QUESTION
What is the composition and stability during storage and culture of fifteen commercially available human preimplantation embryo culture media?
SUMMARY ANSWER
No two culture ...media had the same composition, and both storage and culture had an effect on the concentrations of multiple components.
WHAT IS KNOWN ALREADY
The choice of embryo culture medium not only affects the success rate of an IVF treatment, but also affects the health of the future child. Exact formulations of embryo culture media are often not disclosed by manufacturers. It is unknown whether the composition of these media changes during storage or culture in the IVF laboratory. Without details on the exact concentrations, it is not possible to determine which components might be responsible for the differences in IVF success rates and health of the resulting children.
STUDY DESIGN, SIZE, DURATION
Between October 2014 and October 2015, all complete human preimplantation embryo culture media, i.e. ready to use for IVF, that were commercially available at that time, were included (n = 15). Osmolality and the concentration of thirty seven components including basic elements, metabolites, immunoglobulins, albumin, proteins and 21 amino acids were tested immediately upon arrival into the IVF laboratory, after three days of culture without embryos (sham culture) starting from the day of arrival, just before the expiry date, and after three days of sham culture just before the expiry date.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Ions, glucose, immunoglobulins, albumin and the total amount of proteins were quantified using a combination of ion selective electrodes and photometric analysis modules, and lactate, pyruvate and 21 amino acids were analysed by ultra performance liquid chromatography mass spectrometry. Osmolality was analysed by an advanced micro-osmometer. Statistical analysis was done using multivariate general linear models.
MAIN RESULTS AND THE ROLE OF CHANCE
The composition varied between media, no two media had the same concentration of components. Storage led to significant changes in 17 of the 37 analyzed components (magnesium, chloride, phosphate, albumin, total amount of proteins, tyrosine, tryptophan, alanine, methionine, glycine, leucine, glutamine, asparagine, arginine, serine, proline, and threonine). Storage affected the osmolality in 3 of the 15 media, but for all media combined this effect was not significant (p = 0.08). Sham culture of the analyzed media had a significant effect on the concentrations of 13 of the 37 analyzed components (calcium, phosphate, albumin, total amount of proteins, tyrosine, alanine, methionine, glycine, leucine, asparagine, arginine, proline, and histidine). Sham culture significantly affected the osmolality of the analysed culture media. Two media contained 50% D-lactate, which a toxic dead-end metabolite. In a secondary analysis we detected human liver enzymes in more than half of the complete culture media.
LIMITATIONS, REASONS FOR CAUTION
The analyzed culture media could contain components that are not among the 37 components that were analyzed in this study. The clinical relevance of the varying concentrations is yet to be determined.
WIDER IMPLICATIONS OF THE FINDINGS
The presence of D-lactate could be avoided and the finding of human liver enzymes was surprising. The wide variation between culture media shows that the optimal composition is still unknown. This warrants further research as the importance of embryo culture media on the efficacy and safety in IVF is evident. Companies are urged to fully disclose the composition of their culture media, and provide clinical evidence supporting the composition or future changes thereof.
STUDY FUNDING/COMPETING INTEREST(S)
None.
Abstract
STUDY QUESTION
Can an externally validated model, based on biological variables, be developed to predict successful sperm retrieval with testicular sperm extraction (TESE) in men with ...non-obstructive azoospermia (NOA) using a large nationwide cohort?
SUMMARY ANSWER
Our prediction model including six variables was able to make a good distinction between men with a good chance and men with a poor chance of obtaining spermatozoa with TESE.
WHAT IS KNOWN ALREADY
Using ICSI in combination with TESE even men suffering from NOA are able to father their own biological child. Only in approximately half of the patients with NOA can testicular sperm be retrieved successfully. The few models that have been developed to predict the chance of obtaining spermatozoa with TESE were based on small datasets and none of them have been validated externally.
STUDY DESIGN, SIZE, DURATION
We performed a retrospective nationwide cohort study. Data from 1371 TESE procedures were collected between June 2007 and June 2015 in the two fertility centres.
PARTICIPANTS/MATERIALS, SETTING, METHODS
All men with NOA undergoing their first TESE procedure as part of a fertility treatment were included. The primary end-point was the presence of one or more spermatozoa (regardless of their motility) in the testicular biopsies.
We constructed a model for the prediction of successful sperm retrieval, using univariable and multivariable binary logistic regression analysis and the dataset from one centre. This model was then validated using the dataset from the other centre. The area under the receiver-operating characteristic curve (AUC) was calculated and model calibration was assessed.
MAIN RESULTS AND THE ROLE OF CHANCE
There were 599 (43.7%) successful sperm retrievals after a first TESE procedure. The prediction model, built after multivariable logistic regression analysis, demonstrated that higher male age, higher levels of serum testosterone and lower levels of FSH and LH were predictive for successful sperm retrieval. Diagnosis of idiopathic NOA and the presence of an azoospermia factor c gene deletion were predictive for unsuccessful sperm retrieval. The AUC was 0.69 (95% confidence interval (CI): 0.66–0.72). The difference between the mean observed chance and the mean predicted chance was <2.0% in all groups, indicating good calibration. In validation, the model had moderate discriminative capacity (AUC 0.65, 95% CI: 0.62–0.72) and moderate calibration: the predicted probability never differed by more than 9.2% of the mean observed probability.
LIMITATIONS, REASONS FOR CAUTION
The percentage of men with Klinefelter syndrome among men diagnosed with NOA is expected to be higher than in our study population, which is a potential selection bias. The ability of the sperm retrieved to fertilize an oocyte and produce a live birth was not tested.
WIDER IMPLICATIONS OF THE FINDINGS
This model can help in clinical decision-making in men with NOA by reliably predicting the chance of obtaining spermatozoa with TESE.
STUDY FUNDING/COMPETING INTEREST
This study was partly supported by an unconditional grant from Merck Serono (to D.D.M.B. and K.F.) and by the Department of Obstetrics and Gynaecology of Radboud University Medical Center, Nijmegen, The Netherlands, the Department of Obstetrics and Gynaecology, Jeroen Bosch Hospital, Den Bosch, The Netherlands, and the Department of Obstetrics and Gynaecology, Academic Medical Center, Amsterdam, The Netherlands. Merck Serono had no influence in concept, design nor elaboration of this study.
TRIAL REGISTRATION NUMBER
Not applicable.
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