Number of embryos for transfer following in-vitro fertilisation or intra-cytoplasmic sperm injection

Obstetric Outcomes and Successful Reduction of Twin Pregnancies Achieved by In Vitro Fertilization

The use of in vitro fertilization methods around the world is constantly increasing. In some developed countries, up to 5% of newborns are as a result of pregnancies after IVF procedures. In vitro fertilization as one of the main and widespread methods for treatment of infertility is the main reason for the high frequency of multiple pregnancies, which, in many countries, is still too high. Most of the multiple pregnancies are in fact twin pregnancies. Twin pregnancies, regardless of how they are achieved, are associated with large number of complications compared with singleton ones. More often these pregnancies can lead to maternal complications and adverse pregnancy outcomes. Maternal complications include development of preeclampsia, gestational diabetes, placenta previa, placental abruption, premature rupture of membranes, antepartum and postpartum hemorrhage, and delivery by cesarean sections. Adverse pregnancy outcomes mostly include preterm birth (PTB), low birth weight (LBW), small for gestational age newborn (SGA), intrauterine growth restriction (IUGR), neonatal respiratory distress syndrome (RDS), and admission to neonatal intensive care unit (NICU). A number of studies have found differences in the course of twin pregnancies according to their mode of occurrence – spontaneous or after IVF. Some of them have found that twin pregnancies after IVF are associated with poorer obstetric and perinatal outcomes, others do not find such a difference, and there are even studies that find a better outcome in IVF twin pregnancies. Twin pregnancy is a common occurrence after IVF procedure, because multiple-embryo transfer is commonly regarded as an effective strategy to improve the likelihood of a successful pregnancy. Understanding the risks of these pregnancies should be a strong motive for the transfer of fewer embryos during IVF procedures. The most effective way to do this is to transfer a single-embryo into the uterus in cases, where this is justified and the chances of getting pregnant are high. An important element in achieving this goal is the use of methods for vitrification of embryos, which leads to a sufficiently high rate of clinical pregnancies after freezing of embryos obtained by IVF and their subsequent transfer after thawing in case of failure of fresh ET.

Effectiveness and Safety of Two Consecutive Cycles of Single Embryo Transfer Compared With One Cycle of Double Embryo Transfer: A Systematic Review and Meta-Analysis

OBJECTIVE

To date, evidence regarding the effectiveness and safety of two consecutive cycles of single embryo transfer (2SETs) compared with one cycle of double embryo transfer (DET) has been inadequate, particularly considering infertile women with different prognostic factors. This study aimed to comprehensively summarize the evidence by comparing 2SETs with DET.

METHODS

PubMed, Embase, Cochrane Library databases, ClinicalTrails.gov, and the WHO International Clinical Trials Registry Platform were searched up to March 22, 2022. Peer-reviewed, English-language randomized controlled trials (RCTs) and observational studies (OS) comparing the outcomes of 2SETs with DET in infertile women with their own oocytes and embryos were included. Two authors independently conducted study selection, data extraction, and bias assessment. The Mantel-Haenszel random-effects model was used for pooling RCTs, and a Bayesian design-adjusted model was conducted to synthesize the results from both RCTs and OS.

MAIN RESULTS

Twelve studies were finally included. Compared with the DET, 2SETs were associated with a similar cumulative live birth rate (LBR; 48.24% vs. 48.91%; OR, 0.97; 95% credible interval (CrI), 0.89-1.13, τ^{2 =} 0.1796; four RCTs and six observational studies; 197,968 women) and a notable lower cumulative multiple birth rate (MBR; 0.87% vs. 17.72%; OR, 0.05; 95% CrI, 0.02-0.10, τ^{2 =} 0.1036; four RCTs and five observational studies; 197,804 women). Subgroup analyses revealed a significant increase in cumulative LBR (OR, 1.33; 95% CrI, 1.29-1.38, τ^{2 =} 0) after two consecutive cycles of single blastocyst transfer compared with one cycle of double blastocyst transfer. Moreover, a lower risk of cesarean section, antepartum hemorrhage, preterm birth, low birth weight, and neonatal intensive care unit admission but a higher gestational age at birth and birth weight were found in the 2SETs group.

CONCLUSION

Compared to the DET strategy, 2SETs result in a similar LBR while simultaneously reducing the MBR and improving maternal and neonatal adverse outcomes. The 2SETs strategy appears to be especially beneficial for women aged ≤35 years and for blastocyst transfers.

The human factor: does the operator performing the embryo transfer significantly impact the cycle outcome?

STUDY QUESTION

Is Ongoing Pregnancy Rate (OPR) operator-dependent, and can experience improve embryo transfer efficiency?

SUMMARY ANSWER

OPR is influenced by the operators who perform the embryo transfer (ET), and experience does not assure proficiency for everyone.

WHAT IS KNOWN ALREADY

ET remains the critical step in assisted reproduction. Although many other factors such as embryo quality and uterine receptivity impact embryo implantation, the proper ET technique is clearly an operator-dependent variable and as such it should be objectively standardized.

STUDY DESIGN, SIZE, DURATION

Retrospective comparative analysis including all fresh ETs performed between January 1996 and December 2016 at the Humanitas Fertility Center after IVF—ICSI cycles.

PARTICIPANTS/MATERIALS, SETTING, METHODS

IVF/ICSI fresh ETs performed by 32 operators, 19 824 cycles in all, were analyzed. All transfers consisting of freehand insertion of a preloaded soft catheter into the uterine cavity under transabdominal ultrasound guidance were considered. Two different statistical analyses were performed. First, a logistic regression model with a random intercept for the operator was used to estimate the heterogeneity of the rate of success among operators, accounting for woman age, FSH, number of oocytes retrieved, fertilization rate, year of the procedure, number and stage of transferred embryos and operator’s experience. Second, the relationship between experience and pregnancy rate was estimated separately for each operator by logistic regression, and operator-specific results were combined and compared in a random-effects meta-analysis. In both analyses, the operator’s experience at time t was measured in terms of number of embryo transfers performed before t.

MAIN RESULTS AND THE ROLE OF CHANCE

The heterogeneity among operators was highly significant (P value <0.001) and explained 44.5% of the total variability. The odds ratio of success of the worst operator in respect to the mean was equal to 0.84. For the best operator, the odds ratio of success was equal to 1.13 in respect to the mean. Based on the meta-analysis of the relationship between operator’s experience and success rate, it resulted that, on average, the operators’ performance did not improve with additional transfers.

LIMITATIONS, REASONS FOR CAUTION

At our center, operators become independent for ET’s after performing between 30 and 50 transfers under supervision. It is also possible that other relevant factors, such as embryologists on duty for the ET, have not been included in the present analysis and this may represent a potential bias. Among these, it should be mentioned that the embryologists on duty for the ET were not taken into consideration.

WIDER IMPLICATIONS OF THE FINDINGS

Continued performance analysis and the use of a digital simulator could help operators to test their expertise over time and either correct poor performance or avoid doing transfers.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

NCT03561129.

Number of embryos for transfer following in vitro fertilisation or intra-cytoplasmic sperm injection

BACKGROUND

Transfer of more than one embryo during in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) increases multiple pregnancy rates resulting in an increased risk of maternal and perinatal morbidity. Elective single embryo transfer offers a means of minimising this risk, but this potential gain needs to be balanced against the possibility of jeopardising the overall live birth rate (LBR).

OBJECTIVES

To evaluate the effectiveness and safety of different policies for the number of embryos transferred in infertile couples undergoing assisted reproductive technology cycles.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group specialised register of controlled trials, CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform from inception to March 2020. We handsearched reference lists of articles and relevant conference proceedings. We also communicated with experts in the field regarding any additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different policies for the number of embryos transferred following IVF or ICSI in infertile women. Studies of fresh or frozen and thawed transfer of one to four embryos at cleavage or blastocyst stage were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial eligibility and risk of bias. The primary outcomes were LBR and multiple pregnancy rate. The secondary outcomes were clinical pregnancy and miscarriage rates. We analysed data using risk ratios (RR), Peto odds ratio (Peto OR) and a fixed effect model.

MAIN RESULTS

We included 17 RCTs in the review (2505 women). The main limitation was inadequate reporting of study methods and moderate to high risk of performance bias due to lack of blinding. A majority of the studies had low numbers of participants. None of the trials compared repeated single embryo transfer (SET) with multiple embryo transfer. Reported results of multiple embryo transfer below refer to double embryo transfer. Repeated single embryo transfer versus multiple embryo transfer in a single cycle Repeated SET was compared with double embryo transfer (DET) in four studies of cleavage-stage transfer. In these studies the SET group received either two cycles of fresh SET (one study) or one cycle of fresh SET followed by one frozen SET (three studies). The cumulative live birth rate after repeated SET may be little or no different from the rate after one cycle of DET (RR 0.95, 95% CI (confidence interval) 0.82 to 1.10; I² = 0%; 4 studies, 985 participants; low-quality evidence). This suggests that for a woman with a 42% chance of live birth following a single cycle of DET, the repeated SET would yield pregnancy rates between 34% and 46%. The multiple pregnancy rate associated with repeated SET is probably reduced compared to a single cycle of DET (Peto OR 0.13, 95% CI 0.08 to 0.21; I² = 0%; 4 studies, 985 participants; moderate-quality evidence). This suggests that for a woman with a 13% risk of multiple pregnancy following a single cycle of DET, the risk following repeated SET would be between 0% and 3%. The clinical pregnancy rate (RR 0.99, 95% CI 0.87 to 1.12; I² = 47%; 3 studies, 943 participants; low-quality evidence) after repeated SET may be little or no different from the rate after one cycle of DET. There may be little or no difference in the miscarriage rate between the two groups. Single versus multiple embryo transfer in a single cycle A single cycle of SET was compared with a single cycle of DET in 13 studies, 11 comparing cleavage-stage transfers and three comparing blastocyst-stage transfers.One study reported both cleavage and blastocyst stage transfers. Low-quality evidence suggests that the live birth rate per woman may be reduced in women who have SET in comparison with those who have DET (RR 0.67, 95% CI 0.59 to 0.75; I² = 0%; 12 studies, 1904 participants; low-quality evidence). Thus, for a woman with a 46% chance of live birth following a single cycle of DET, the chance following a single cycle of SET would be between 27% and 35%. The multiple pregnancy rate per woman is probably lower in those who have SET than those who have DET (Peto OR 0.16, 95% CI 0.12 to 0.22; I² = 0%; 13 studies, 1952 participants; moderate-quality evidence). This suggests that for a woman with a 15% risk of multiple pregnancy following a single cycle of DET, the risk following a single cycle of SET would be between 2% and 4%. Low-quality evidence suggests that the clinical pregnancy rate may be lower in women who have SET than in those who have DET (RR 0.70, 95% CI 0.64 to 0.77; I² = 0%; 10 studies, 1860 participants; low-quality evidence). There may be little or no difference in the miscarriage rate between the two groups.

AUTHORS' CONCLUSIONS

Although DET achieves higher live birth and clinical pregnancy rates per fresh cycle, the evidence suggests that the difference in effectiveness may be substantially offset when elective SET is followed by a further transfer of a single embryo in fresh or frozen cycle, while simultaneously reducing multiple pregnancies, at least among women with a good prognosis. The quality of evidence was low to moderate primarily due to inadequate reporting of study methods and absence of masking those delivering, as well as receiving the interventions.

Preimplantation Genetic Testing: Where We Are Today

BACKGROUND

Preimplantation genetic testing (PGT) is widely used today in in-vitro fertilization (IVF) centers over the world for selecting euploid embryos for transfer and to improve clinical outcomes in terms of embryo implantation, clinical pregnancy, and live birth rates.

METHODS

We report the current knowledge concerning these procedures and the results from different clinical indications in which PGT is commonly applied.

RESULTS

This paper illustrates different molecular techniques used for this purpose and the clinical significance of the different oocyte and embryo stage (polar bodies, cleavage embryo, and blastocyst) at which it is possible to perform sampling biopsies for PGT. Finally, genetic origin and clinical significance of embryo mosaicism are illustrated.

CONCLUSIONS

The preimplantation genetic testing is a valid technique to evaluated embryo euploidy and mosaicism before transfer.

FSH dose to stimulate different patient' ages: when less is more

Objective

To determine the effect of FSH doses on intracytoplasmic sperm injection (ICSI) outcomes according to the age of the patient.

Methods

Patients undergoing controlled ovarian stimulation (COS) for ICSI cycles in a university-affiliated in vitro fertilization center were split into age groups: ≤35 y.o. (n=1523); >35 and ≤38 y.o. (n=652); >38 and ≤40 y.o. (n=332); and >40 y.o. (n=370). The effect of FSH dose on COS, laboratorial and clinical outomes was determined by linear regression models.

Results

The FSH dose didn't affect the ovarian response in terms of total number of follicles, retrieved oocytes and mature oocytes within the age groups, but we found that the lower the age, the lower the FSH dose needed per oocyte retrieved. In the group of patients ≤35 y.o., we also found a positive effect of the FSH dose on oocyte yield. Despite that, for patients ≤38 y.o. there was a negative effect of the FSH dose on embryo quality and blastocyst formation rate, and an increase in the cycle's cancelation rate. In patients ≥39 y.o., there were no effects of the FSH doses on the analysed variables.

Conclusions

Ovarian stimulation with high doses of FSH is not recommended in younger women (≤38 y.o.), once we found a decrease in embryo quality and an increase in cycle's cancelation rate. Mild ovarian stimulation protocols may be more appropriate; however, it may not be applicable for women in advanced age, since a higher FSH dose is needed for oocyte retrieval in these patients.

miR-142-3p as a biomarker of blastocyst implantation failure - A pilot study

OBJECTIVE

This study aims to find whether microRNAs (miRNAs) detected in the culture medium of embryos produced in vitro could be potential biomarkers of embryo implantation.

METHODS

Culture media samples from 36 embryos, derived from patients undergoing intracytoplasmic sperm injection (ICSI) in a private university-affiliated IVF center, were collected between January/2015 and November/2015. Samples were collected on day three and embryo transfers were performed on day five and all embryos reached the blastocyst stage. Samples were split into groups according to the embryo implantation result: Positive-Implantation-Group (n=18) or Negative-Implantation-Group (n=18). For the first analysis, samples were pooled in three sets for each group (6-7 spent media per pool). MicroRNAs were extracted from spent media and cDNA was synthesized. C. elegans miR-39 was used as RNA spike-in to normalize the gene expression analysis. The expression of microRNAs into the spent media from the Positive-Implantation-Group was compared with those from the Negative-Implantation-Group. A set of seven miRNAs (miR-21, miR-142-3p, miR-19b, miR-92a, miR-20b, miR-125a and miR148a) selected according with the literature, was tested. To check whether miRNAs could be detected in individual samples of culture media, in a second analysis, ten more samples were tested for miR-21 and miR-142-3p.

RESULTS

From the sevens tested miRNAs, a significant increased expression of miR-142-3p could be noted in the Negative-Implantation-Group (P<0.001). For other three miRNAs (miR-21, miR-19b and miR-92a) a difference in expression was observed, however it did not reach a statistical significance. In addition, when ten non-redundant samples were tested to check if miRNAs could be detected in individual samples of culture media, the highly specific amplification of mature miRNAs, including miR-142-3p, could be noted.

CONCLUSION

Our findings suggest that miR-142-3p, previously described as a tumor suppressor and cell cycle inhibitor, may be a potential biomarker of blastocyst implantation failure. The identification of miRNAs on individual culture medium samples offers unique opportunities for non-invasive early diagnosis of blastocyst implantation.

Non-invasive prediction of blastocyst implantation, ongoing pregnancy and live birth, by mass spectrometry lipid fingerprinting

Objective

To identify lipid markers of blastocyst implantation and ongoing pregnancy by day three culture medium mass spectrometry (MS) fingerprinting.

Methods

For this study, 33 culture media samples were harvested on day three, from 22 patients undergoing day five embryo transfers. All embryos achieved the blastocyst stage and were split into groups based on their implantation (Negative Implantation, n= 14 and Positive Implantation, n= 19). The positive implantation cycles resulted in successful ongoing pregnancies. The lipid extraction was performed by the Bligh-Dyer protocol and mass spectra were obtained with a direct infusion into a Q-Tof mass spectrometer. The data obtained was analyzed by Principal Component Analysis (PCA) and Partial Least Square Discrimination Analysis (PLS-DA). The statistical analysis was performed using the Metabo-Analyst 2.0.

Results

The variable importance in the projection (VIP) plot of the PLS-DA provided a list of four ions, in the positive mode, with an area under the curve (AUC) of 73.5%; and eight ions, in the negative mode, with and AUC of 72.0%. For both positive and negative modes, possible biomarkers for the negative implantation were identified by the lipidmaps: phosphoethanolamine, dicarboxylic acids, glycerophosphoglycerol, glycerophosphocholine, glicerophosphoinositol, phosphoethanolamine and unsaturated fat acids. The other ions were not identified. These lipids are involved in the GPI anchor biosynthesis and synthesis of lycerophospholipids and phosphate inositol.

Conclusion

MS fingerprinting is useful to identify blastocysts that fail to implant, and therefore this technique could be incorporated into the laboratory routine, adjunct to morphology evaluation to identify embryos that should not be transferred.

Follicular fluid biomarkers for human in vitro fertilization outcome: Proof of principle

Background

Human follicular fluid (FF) is a unique biological fluid in which the oocyte develops in vivo, and presents an optimal source for non-invasive biochemical predictors. Oocyte quality directly influences the embryo development and hence, may be used as a predictor of embryo quality. Peptide profiling of FF and its potential use as a biomarker for oocyte quality has never been reported.

Methods

This study screened FF for peptide biomarkers that predict the outcome of in vitro fertilization (IVF). Potential biomarkers were discovered by investigating 2 training datasets, consisting both of 17 samples and validating on an independent experiment containing 32 samples. Peptide profiles were acquired by nano-scale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS).

Results

From the training datasets 53 peptides were found as potential biomarker candidates, predicting the fertilization outcome of 24 out of the 32 validation samples blindly (81.3% sensitivity, 68.8% specificity, AUC = 0.86). Seven potential biomarker peptides were identified. They were derived from: insulin-like growth factor binding protein-5, alpha-2-antiplasmin, complement component 3, inter-alpha-trypsin inhibitor heavy chain H1, serum albumin, protein diaphanous homolog 1 and plastin-3.

Conclusions

The MS-based comprehensive peptidomic approach carried out in this study, established a novel panel of potential biomarkers that present a promising predictive accuracy rate in fertilization outcome, and indicates FF as an interesting biomarker resource to improve IVF clinic routine.

Electronic supplementary material

The online version of this article (doi:10.1186/s12953-016-0106-9) contains supplementary material, which is available to authorized users.

Protein expression in human cumulus cells as an indicator of blastocyst formation and pregnancy success

PURPOSE

The goal for the present study was to implement a technique for protein extraction and identification in human cumulus cells (CCs).

METHODS

Forty samples of CCs were collected after ovum pick-up from patients undergoing intracytoplasmic sperm injection (ICSI). Samples were split into the blastocyst group (n = 10), including patients in which all embryos converted into blastocysts, and the non-blastocyst group (n = 10), including patients in which none of the embryos reached the blastocyst stage or the positive-pregnancy (n = 10) and negative-pregnancy group (n = 10). Proteins were extracted and injected into a liquid chromatography system coupled to a mass spectrometer. The spectra were processed and used to search a database.

RESULTS

There were 87 different proteins in samples from the blastocyst and non-blastocyst groups, in which 30 were exclusively expressed in the blastocyst group and 17 in the non-blastocyst group. Among the 72 proteins detected in the pregnancy groups, 19 were exclusively expressed in the positive, and 16 were exclusively expressed in the negative-pregnancy group.

CONCLUSIONS

CC proteomics may be useful for predicting pregnancy success and the identification of patients that should be included in extended embryo culture programs.

Promoting the use of elective single embryo transfer in clinical practice

Background

The transfer of multiple embryos after in vitro fertilization (IVF) increases the risk of twins and higher-order births. Multiple births are associated with significant health risks and maternal and neonatal complications, as well as physical, emotional, and financial stresses that can strain families and increase the incidence of depression and anxiety disorders in parents. Elective single embryo transfer (eSET) is among the most effective methods to reduce the risk of multiple births with IVF.

Main body

Current societal guidelines recommend eSET for patients <35 years of age with a good prognosis, yet even this approach is not widely applied. Many patients and clinicians have been reluctant to adopt eSET due to studies reporting higher live birth rates with the transfer of two or more embryos rather than eSET. Additional barriers to eSET include risk of treatment dropout after embryo transfer failure, patient preference for twins, a lack of knowledge about the risks and complications associated with multiple births, and the high costs of multiple IVF cycles. This review provides a comprehensive summary of strategies to increase the rate of eSET, including personalized counseling, access to educational information regarding the risks of multiple pregnancies and births, financial incentives, and tools to help predict the chances of IVF success. The use of comprehensive chromosomal screening to improve embryo selection has been shown to improve eSET outcomes and may increase acceptance of eSET.

Conclusions

eSET is an effective method for reducing multiple pregnancies resulting from IVF. Although several factors may impede the adoption of eSET, there are a number of strategies and tools that may encourage the more widespread adoption of eSET in clinical practice.

Outcomes of elective cryopreserved single or double embryo transfers following failure to conceive after fresh single embryo transfer

The main adverse effect of IVF is the high multiple pregnancy rate resulting from the transfer of two or more embryos. The objective was to evaluate pregnancy rates in infertile women with a good prognosis who failed to conceive in a fresh elective single embryo transfer (eSET) and had a second cycle with elective double vitrified-warmed embryo transfer (eDFET) compared with elective single vitrified-warmed embryo transfer (eSFET). A total of 142 intracytoplasmic sperm injection cycles using a conventional protocol were evaluated. Good-prognosis patients underwent eSET in a fresh cycle, and those who failed to conceive underwent a second vitrified-warmed embryo transfer: eDFET (n = 102) or eSFET (n = 40). Embryos were transferred and vitrified on day 5 of development. Patients who received eDFET had fewer implantations (30.9%) than eSFET (52.5%; P = 0.004); pregnancy rates were similar (eDFET: 35.3%, eSFET: 42.5%). Patients with the eSFET had one monozygotic twin (5.9%), and 22.2% of eDFET patients had multiple pregnancies. Patients with a good prognosis who failed to conceive in the first fresh eSET did not have an advantage when receiving eDFET in the second cycle, as pregnancy rates were similar; 22.2% of patients in the eDFET group had multiple pregnancies.

A greater number of euploid blastocysts in a given cohort predicts excellent outcomes in single embryo transfer cycles

PURPOSE

This multicentered retrospective study analyzed whether the quantity of euploid blastocysts in a given cohort after comprehensive chromosomal screening can be used to identify candidates for single embryo transfer.

METHODS

Blastocysts from 437 patients underwent trophectoderm biopsy followed by array comparative genomic hybridization. Embryos were then selected for single or double embryo transfer. The number of euploid blastocysts produced and transferred for each patient was recorded, as was clinical pregnancy rate and multiple gestation rate.

RESULTS

In patients with ≤ 3 euploid blastocysts, clinical pregnancy rate was higher in double, compared to single embryo transfers. However, in patients with ≥ 4 euploid blastocysts, clinical pregnancy rate was not reduced with single embryo transfer was performed, whereas the multiple gestation rate was greatly reduced.

CONCLUSIONS

Size of the euploid embryo cohort is a marker for success in single embryo transfer cycles. Patients who produce at least four euploid blastocysts are outstanding candidates for single embryo transer.

Debating Elective Single Embryo Transfer after in vitro Fertilization: A Plea for a Context-Sensitive Approach

The number of embryos transferred after in vitro fertilization (IVF) have been a topic of debate for over a decade now. Due to the risk associated with multiple pregnancy, there has been a global effort at reducing the multiple pregnancy rates to a minimum while maintaining an acceptable level of successful IVF pregnancy rate. Elective single embryo transfer (eSET) is advocated in most European countries. In Belgium and Sweden, eSET is mandatory for couples with a good prognosis. However, despite clinical recommendations and policy statements, patients in clinical practice frequently do request for the transfer of multiple embryos in order to have twins. Such requests conflict with policy guidelines and create an ethical dilemma for physicians: Should the physician do as the couple requests, and there with respect the autonomy of patients, or adhere to medical policy that takes the health of the mother and children at heart? This article provides an exploration of the arguments found in the literature that plays a role in the discussion on this topic and eventually argues that what a physician should do depends on the specificities of the context in which patients and physicians are implicated. These contextual issues can be taken into account in a shared decision-making procedure, which allows reflections and the responsibilities of both patients and physicians to be attended in decision about assisted reproduction.

Assisted reproductive technologies (ARTs): evaluation of evidence to support public policy development

Over the years, IVF/ICSI protocols have continued to evolve with efforts to improve outcomes. As a result, treatment success may be related to certain procedural factors, including number of embryos transferred and stage at which they are transferred. This review aims to assess the safety and effectiveness of IVF/ICSI in comparison to spontaneous conception and less invasive ARTs and the impact of procedure-related factors on the outcomes of IVF/ICSI in order to support the development of local clinical and policy guidance. Following Cochrane Collaboration guidelines and the PRISMA statement, a comprehensive systematic review of literature examining the impact of procedural characteristics on the safety or effectiveness of IVF/ICSI from 2007 to date was performed. 33 systematic reviews and 3 primary studies evaluating the impact of procedural differences, IVF/ICSI in comparison to less invasive ARTs, and ARTs in comparison to spontaneous conception were found. IVF was shown to offer significant benefits over no treatment and IUI in achieving pregnancy and live birth among couples with endometriosis or unexplained infertility. Frozen and blastocyst-stage embryo transfers were as effective as fresh and cleavage-stage embryo transfers, respectively. In comparison to single embryo transfer, double embryo transfer significantly increased pregnancy, live birth and multiple pregnancy/birth rates. IVF/ICSI was associated with more complications during pregnancy and delivery, and in infants compared to naturally conceived pregnancies, particularly when multiple embryo transfer was used. Frozen embryo transfer had fewer adverse events during pregnancy and delivery than fresh embryo transfer, and was at least as safe in terms of infant outcomes. The potential complications of IVF/ICSI may be minimized through procedural choices, but such choices often impact effectiveness. Thus, in developing clinical and policy guidance around IVF/ICSI, the risk-benefit trade-offs patients and providers are willing to accept must be carefully considered.

The Desire for Multiple Pregnancy among Patients with Infertility and Their Partners

Objective. To study the predictors for desire for multiple pregnancies and the influence of providing information regarding the maternal and fetal complications associated with multiple pregnancies on their preference for multiple pregnancies. Methods. Couples attending an infertility clinic were offered to fill up a questionnaire separately. Following this, they were handed a pamphlet with information regarding the risks associated with multiple pregnancies. The patients will then be required to answer the question on the number of pregnancies desired again. Results. Two hundred fifty three out of 300 respondents completed the questionnaires adequately. A higher proportion of respondents, 60.3% of females and 57.9% of males, prefer singleton pregnancy. Patients who are younger than 35 years, with preexisting knowledge of risks associated with multiple pregnancies and previous treatment for infertility, have decreased desire for multiple pregnancies. However, for patients who are older than 35, with longer duration of infertility, and those patients who have preexisting knowledge of the increased risk, providing further information regarding the risks did not change their initial preferences. Conclusion. Providing and reinforcing knowledge on the risks to mother and fetus associated with multiple pregnancies did not decrease the preference for multiple pregnancies in patients.

Quality of additional embryos transferred on pregnancy outcomes in IVF: predictions using a mathematical approach

This study assessed the influence of adding embryos with different embryo quality on pregnancy rate and multiple pregnancy rate (MPR). The study included 1891 IVF transfers performed at two centres with different embryo transfer policies. Pregnancy rate and MPR were analysed following three models and then including embryo quality. A predictive mathematical model and two scatter plots were constructed. The model based on embryo independence was incompatible with the observed data, while both the ground and collaborative models provided excellent fits. The collaborative model, however, predicted multiple pregnancies, especially triplets, more accurately. Transfer of additional embryos, irrespective of embryo quality, always increased pregnancy rate and MPR. When implantation rate was low, there was a marked increase in pregnancy rate but only a relatively small increase in MPR. In contrast, with higher implantation rates, the increase in pregnancy rate was mainly due to the increase in MPR, with the same singleton pregnancy rate. Transfer of additional embryos, irrespective of embryo quality, follows a collaborative pattern and always results in an increase in pregnancy rate and MPR. The scatter plots accurately predicted the influence of the different combinations of number and embryo quality on pregnancy rate and MPR.

Perinatal mortality following assisted reproductive technology treatment in Australia and New Zealand, a public health approach for international reporting of perinatal mortality

BACKGROUND

There is a need to have uniformed reporting of perinatal mortality for births following assisted reproductive technology (ART) treatment to enable international comparison and benchmarking of ART practice.

METHODS

The Australian and New Zealand Assisted Reproduction Database was used in this study. Births of ≥ 20 weeks gestation and/or ≥ 400 grams of birth weight following embryos transfer cycles in Australia and New Zealand during the period 2004 to 2008 were included. Differences in the mortality rates by different perinatal periods from a gestational age cutoff of ≥ 20, ≥ 22, ≥ 24, or ≥ 28 weeks (wks) to a neonatal period cutoff of either < 7 or < 28 days after birth were assessed. Crude and specific (number of embryos transferred and plurality) rates of perinatal mortality were calculated for selected gestational and neonatal periods.

RESULTS

When the perinatal period is defined as ≥ 20 wks gestation to < 28 days after birth, the perinatal mortality rate (PMR) was 16.1 per 1000 births (n = 630). A progressive contraction of the gestational age groups resulted in marked reductions in the PMR for deaths at < 28 days (22 wks 11.0; 24 wks 7.7; 28 wks 5.6); and similarly for deaths at < 7 days (20 wks 15.6, 22 wks 10.5; 24 wks 7.3; 28 wks 5.3). In contrast, a contraction of the perinatal period from < 28 to < 7 days after birth only marginally reduced the PMR from 16.2 to 15.6 per 1000 births which was consistent across all gestational ages.The PMR for single embryo transfer (SET) births (≥ 20 weeks gestation to < 7 days post-birth) was significantly lower (12.8 per 1000 SET births) compared to double embryo transfer (DET) births (PMR 18.3 per 1000 DET births; p < 0.001, Fisher's Exact Test). Similarly, the PMR for SET births (≥ 22 weeks gestation to < 7 days post-birth) was significantly lower (8.8 per 1000 SET births, p < 0.001, Fisher's Exact Test) when compared to DET births (12.2 per 1000 DET births). The highest PMR (50.5 per 1000 SET births, 95% CI 36.5-64.5) was for twins following SET births (≥ 20 weeks gestation to < 7 days post-birth) compared to twins following DET (23.9 per 1000 DET births, 95% CI 20.8-27.1).

CONCLUSION

Reporting of perinatal mortality of ART births is an essential component of quality ART practice. This should include measures that monitor the impact on perinatal mortality of multiple embryo transfer. We recommend that reporting of perinatal deaths following ART treatment, should be stratified for three gestation-specific perinatal periods of ≥ 20, ≥ 22 and ≥ 28 completed weeks to < 7 days post-birth; and include plurality specific rates by SET and DET. This would provide a valuable international evidence-base of PMR for use in evaluating ART policy, practice and new research.

Economic evaluation of highly purified human menopausal gonadotropin versus recombinant human follicle-stimulating hormone in fresh and frozen in vitro fertilization/intracytoplasmic sperm-injection cycles in Sweden

Gonadotropin-releasing hormone-analog type, fertilization method, and number of embryos available for cryopreservation should be incorporated into economic evaluations of highly purified human menopausal gonadotropin (HP-hMG) and recombinant human follicle-stimulating hormone (r-hFSH), as they may affect treatment costs. We searched for randomized trials and meta-analyses comparing HP-hMG and r-hFSH. Meta-analysis showed no significant difference in live births (odds ratio 0.82, 95% confidence interval [CI] 0.66–1.01), but a greater number of oocytes with r-hFSH (mean difference [MD] 1.96, 95% CI 1.02–2.90). Using a cost-minimization model for Sweden, accounting for embryo availability, survival following thawing, and patient dropout, we simulated patients individually for up to three cycles. R-hFSH was found to be cost-saving, at 2,767 kr (95% CI 1,580–4,057) per patient (€315 or $411); baseline savings were 6.43% of the total HP-hMG cost. In fresh cycles only, the savings for r-hFSH were 1,752 kr (95% CI 48–3,658) per patient (€200 or $260). In univariate sensitivity analyses, savings were obtained until the price of r-hFSH increased by 30% or the dosage of HP-hMG decreased by 38%–62% of baseline value. In probabilistic sensitivity analysis, r-hFSH was cost-saving in 100% of the simulated cohort per patient and in 85% per live birth; the respective percentages for fresh cycles only were 97.3% and 73.1%. In conclusion, a greater number of oocytes with r-hFSH allows for more frozen embryo transfers, thereby reducing overall treatment cost.

Mistaken advocacy against twin pregnancies following IVF

PURPOSE

A recent publication by Swedish Colleagues in Fertility & Sterility for the first time, statistically correctly, attempted to assess risks of twin IVF pregnancies in comparison to two consecutive singleton IVF pregnancies. Historic comparisons have been statistically incorrect, comparing risks of one twin to one singleton pregnancy. We here analyze data and conclusions presented in this Swedish study.

METHODS

We reviewed the manuscript by Sazonova et al. (Fertil Steril, 2013) (doi: 10.1016/j.fertnstert.2012.11.023 ).

RESULTS

Based on incorrect statistical methodology, twins after in vitro fertilization (IVF) have come under attack as "adverse" outcomes. Above noted study recently, for the first time, correctly compared one twin to two consecutive singleton pregnancies. Investigators, however, in our opinion interpreted their own data incorrectly by claiming "dramatically" higher maternal and neonatal risks in twin pregnancies. Our interpretation of reported data, indeed, in contrast suggests surprisingly minor differences in observed twin-risks. Moreover, such minor risk increases do not offer adequate compensatory benefits for significantly lower pregnancy chances in first IVF cycles with eSET in comparison to two-embryo transfers (2-ET).

CONCLUSIONS

As significantly higher maternal and neonatal risks of twin IVF pregnancies represent the principal rationale for eSET, the Swedish study actually suggests that eSET offers neither patient-friendly nor cost-effective treatment options for IVF, except where patients object to twins or have medical contraindications. The need for a second pregnancy to achieve equal outcome (2 children), resulting treatment delays, increased efforts and costs, in absence of any guarantees that a second successful singleton pregnancy/delivery will ever be accomplished, invalidates eSET as a routine procedure.

A decrease in serum estradiol levels after human chorionic gonadotrophin administration predicts significantly lower clinical pregnancy and live birth rates in in vitro fertilization cycles

BACKGROUND

Although close observation of serum estradiol (E2) levels remains a mainstay of assessing clinical response to controlled ovarian stimulation, the prognostic value of any change in E2 levels after administration of hCG remains unclear. The objective of this study is to evaluate the relationship between serum E2 response after hCG administration and the clinical pregnancy and live birth rates in fresh IVF cycles.

METHODS

We conducted a retrospective cohort study of women aged 21-45 years undergoing their first IVF cycle from 1999 to 2008 at a single practice. We compared the post-hCG serum E2 level with values on the day of hCG trigger. IVF cycles were stratified by post-hCG E2 response and appropriate parametric and non-parametric statistics were performed. Clinical intrauterine pregnancy and live births were the primary outcomes of interest. Multivariable logistic regression models were created to identify predictive factors associated with outcomes while adjusting for potential confounders.

RESULTS

Among the 1712 IVF cycles, 1065 exhibited a >10% increase (Group A), 525 had a plateau (± 10%, Group B) and 122 showed a >10% decrease (Group C) in post-hCG E2 levels. While the E2 levels on the day of hCG were similar across groups, Group C had more patients with diminished ovarian reserve, required higher gonadotrophin doses and had the lowest implantation rates. After adjusting for age, total gonadotrophin dose, infertility diagnosis, number of oocytes and number of transferred embryos, the associations between post-hCG E2 decline (Group C) and clinical pregnancy [adjusted odds ratio (aOR): 0.53; 95% confidence interval (CI): 0.33-0.84, P= 0.007] and live birth (aOR: 0.40; 95% CI: 0.22-0.71, P= 0.002) were significant. We also found significant associations between E2 plateau (Group B) and clinical pregnancy (aOR: 0.73; 95% CI: 0.57-0.94, P= 0.013) and live birth (aOR: 0.74; 95% CI: 0.56-0.97, P= 0.032) when adjusting for the same factors.

CONCLUSIONS

In our study, >10% decrease in E2 levels after hCG administration was associated with 40-50% reduction in clinical pregnancy and live birth rates. Similarly, post-hCG E2 plateau (± 10%) lowered the clinical pregnancy and live birth rates by >25%. Our study suggests that the change in the post-hCG E2 level is another parameter that can be used by clinicians to counsel patients regarding their likelihood of success with assisted reproductive technologies prior to oocyte retrieval.

Lessons from elective in vitro fertilization (IVF) in, principally, non-infertile women

BACKGROUND

We here report the first investigation of exclusively elective in vitro fertilization (IVF) cycles in women with no apparent history of infertility. Since IVF outcome in women with infertility are always influenced by underlying causes of infertility, a study on non-infertile women may offer new insights.

METHODS

We investigated 88 females without history of infertility in 109 consecutive elective IVF cycles, almost exclusively performed for purposes of preimplantation genetic screening (PGS; i.e., elective gender selection). The following questions were addressed: (i) impact of PGS on IVF pregnancy chances; (ii) impact of transfer of 1 vs. ≥2 embryos on IVF pregnancy chances; (iii) correlation of anti-Müllerian hormone (AMH) levels to embryo ploidy (iv) effect of gonadotropin dosage used in stimulation on available embryos for transfer; and (v) in form of a 1:1 case control study, compared 33 elective PGS cycles with matched control cycles without PGS, performed in couples with either prior tubal ligations and/or severe male factor infertility as indication of IVF.

RESULTS

The overall clinical pregnancy rate for the group was 36.7%; pregnancy was associated with number of euploid (P = 0.009) and number of embryos transferred (P = 0.001). Odds of pregnancy were 3.4-times higher if ≥4 euploid embryos were produced in comparison to <4 (95% CI 1.2 to 9.2; P = 0.019), and odds of pregnancy were 6.6-times higher if greater than or equal to 2 rather than <1 euploid embryos were transferred (95% CI 2.0 to 21.7; P = 0.002). Increasing AMH (P = 0.001) and gonadotropin dosage used in ovarian stimulation (P = 0.024), was, independently, associated with number of available euploid embryos. Increasing AMH, but not follicle stimulating hormone (FSH), was associated with number of embryos available for biopsy and PGS (P = 0.0001). Implantation rates were 26.4% with PGS and 9.5% without (P = 0.008). Women undergoing PGS, demonstrated 4.58-times higher odds of pregnancy than matched controls (95% CI 1.102 to 19.060, Exp 4.584, P = 0.036).

CONCLUSIONS

This study suggests that outcomes of elective IVF cycles may significantly deviate from infertility-associated cycles. Affirming proof of concept for PGS, utilizing day-3 embryo biopsy and fluorescence in-situ hybridization (FISH), both widely held responsible for earlier failures to establish such proof, suggests that the principal cause of prior failures were likely not insufficient laboratory techniques but poor patient selection for PGS. Such a conclusion questions the current reintroduction of PGS with improved techniques and technologies in absence of prior determination of suited patient populations.

Peri-implantation glucocorticoid administration for assisted reproductive technology cycles

BACKGROUND

In order to improve embryo implantation for in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) cycles the use of glucocorticoids has been advocated. It has been proposed that glucocorticoids may improve the intrauterine environment by acting as immunomodulators to reduce the uterine natural killer (NK) cell count and normalise the cytokine expression profile in the endometrium and by suppression of endometrial inflammation.

OBJECTIVES

To investigate whether the administration of glucocorticoids around the time of implantation improved clinical outcomes in subfertile women undergoing IVF or ICSI when compared to no glucocorticoid administration.

SEARCH METHODS

The Cochrane Menstrual Disorders and Subfertility Group Trials Register (September 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (September 2011), MEDLINE (1966 to September 2011), EMBASE (1976 to September 2011), CINAHL (1982 to September 2011) and Science Direct (1966 to September 2011) were searched. Reference lists of relevant articles and relevant conference proceedings were handsearched.

SELECTION CRITERIA

All randomised controlled trials (RCTs) addressing the research question were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility and quality of trials and extracted relevant data.

MAIN RESULTS

Fourteen studies (involving 1879 couples) were included. Three studies reported live birth rate and these did not identify a significant difference after pooling the (preliminary) results (OR 1.21, 95% CI 0.67 to 2.19). With regard to pregnancy rates, there was also no evidence that glucocorticoids improved clinical outcome (13 RCTs; OR 1.16, 95% CI 0.94 to 1.44). However, a subgroup analysis of 650 women undergoing IVF (6 RCTs) revealed a significantly higher pregnancy rate for women using glucocorticoids (OR 1.50, 95% CI 1.05 to 2.13). There were no significant differences in adverse events, but these were poorly and inconsistently reported.

AUTHORS' CONCLUSIONS

Overall, there was no clear evidence that administration of peri-implantation glucocorticoids in ART cycles significantly improved the clinical outcome. The use of glucocorticoids in a subgroup of women undergoing IVF (rather than ICSI) was associated with an improvement in pregnancy rates of borderline statistical significance and should be interpreted with care. These findings were limited to the routine use of glucocorticoids and cannot be extrapolated to women with autoantibodies, unexplained infertility or recurrent implantation failure. Further well designed randomised studies are required to elucidate the possible role of this therapy in well defined patient groups.

Single embryo transfer with comprehensive chromosome screening results in improved ongoing pregnancy rates and decreased miscarriage rates

BACKGROUND

Single embryo transfer (SET) provides the most certain means to reduce the risk of multiple gestation. Regrettably, prospective trials of SET have demonstrated reductions in per-cycle delivery rates. A validated method of comprehensive chromosome screening (CCS) has the potential to optimize SET by transferring only euploid embryos. This retrospective study evaluates the efficacy of SET with CCS in an infertile population.

METHODS

Overall and age-controlled ongoing pregnancy rates (OPR) were compared between women undergoing SET following CCS (CCS-SET, n= 140) and those undergoing SET without aneuploidy screening (control SET, n= 182). All transfers were at the blastocyst stage, with CCS performed after trophectoderm biopsy of expanded blastocysts and analysis with rapid PCR allowing for fresh transfer.

RESULTS

In the CCS-SET and control SET groups, an OPR of 55.0 and 41.8%, respectively, was obtained. The OPR was lower for the control group (P< 0.01) despite a younger age than the CCS group (37.3 ± 3.4 versus 34.2 ± 3.9 years; P< 0.001). Birthweight and gestational age at delivery were equivalent. The proportion of clinical pregnancies resulting in miscarriage was higher in the control group (24.8 versus 10.5%, P< 0.01), with more patients requiring surgical interventions for aneuploid pregnancies. There was one monozygotic twin delivery in the CCS group and none in the control group.

CONCLUSIONS

Compared with traditional blastocyst SET, SET after trophectoderm biopsy and rapid PCR-based CCS increases OPR and reduces the miscarriage rate. The enhanced selection empowered by CCS with SET may provide a practical way to eliminate multi-zygotic multiple gestation without compromising clinical outcomes per cycle.

Cerebral palsy and assisted conception

Assisted reproductive technologies have been widely used over the past 30 years, and 1% to 4% of births worldwide are products of these technologies. However, adverse health outcomes related to assisted reproductive technologies, including cerebral palsy, have been reported. We extracted and reviewed all relevant studies cited by Medline from 1996 to 2010 evaluating the role of assisted reproductive technologies as a causative factor for cerebral palsy and poor long-term neurologic outcome. The research suggests that multiple pregnancy, preterm delivery, and babies small for gestational age are factors in the development of cerebral palsy. The vanishing embryo syndrome may also play a role. We review the evidence for these potentially causative factors, as well as their implications for embryo transfer policies.

Cumulative live-birth rates per total number of embryos needed to reach newborn in consecutive in vitro fertilization (IVF) cycles: a new approach to measuring the likelihood of IVF success

OBJECTIVE

To report the use of cumulative live-birth rates (CLBRs) per ovarian stimulation cycle to measure the success of IVF is proving to be the most accurate method for advising couples who failed to conceive, although the accuracy yielded is relatively low, and cycle outcome is highly dependent on the number of embryos replaced. Our aim with this work is to report the CLBRs of IVF as a function of the number of embryos required to reach a live birth (EmbR), considering age, day of ET, and infertility etiology.

DESIGN

Survival curves and Kaplan-Meier methods to analyze CLBR in a retrospective cohort with respect to the number of EmbR.

SETTING

University-affiliated infertility center.

PATIENT(S)

Infertile couples undergoing IVF using own oocytes.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

CLBR per embryo transferred.

RESULT(S)

CLBRs increase rapidly between 1 and 5 EmbR, moderately between 5 and 15, and slowly thereafter. Live-birth rates rise more slowly when embryos are transferred on days 2-3 rather than on days 5-6, with comparable long-term results. Women's age is a negative factor from 35 to 37 years old, with a dramatic decrease in live-birth rates beyond age 40 years. In addition, there are significant worse results in endometriosis patients.

CONCLUSION(S)

The relationship between CLBR and number of EmbR provides realistic and precise information regarding IVF success and can be used to guide couples and practitioners.

Clinical effectiveness of elective single versus double embryo transfer: meta-analysis of individual patient data from randomised trials

OBJECTIVE

To compare the effectiveness of elective single embryo transfer versus double embryo transfer on the outcomes of live birth, multiple live birth, miscarriage, preterm birth, term singleton birth, and low birth weight after fresh embryo transfer, and on the outcomes of cumulative live birth and multiple live birth after fresh and frozen embryo transfers.

DESIGN

One stage meta-analysis of individual patient data.

DATA SOURCES

A systematic review of English and non-English articles from Medline, Embase, and the Cochrane Central Register of Controlled Trials (up to 2008). Additional studies were identified by contact with clinical experts and searches of bibliographies of all relevant primary articles. Search terms included embryo transfer, randomised controlled trial, controlled clinical trial, single embryo transfer, and double embryo transfer. Review methods Comparisons of the clinical effectiveness of cleavage stage (day 2 or 3) elective single versus double embryo transfer after fresh or frozen in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) treatments were included. Trials were included if the intervention differed only in terms of the intended number of embryos to be transferred. Trials that involved only blastocyst (day five) transfers were excluded.

RESULTS

Individual patient data were received for every patient recruited to all eight eligible trials (n=1367). A total of 683 and 684 women randomised to the single and double embryo transfer arms, respectively, were included in the analysis. Baseline characteristics in the two groups were comparable. The overall live birth rate in a fresh IVF cycle was lower after single (181/683, 27%) than double embryo transfer (285/683, 42%) (adjusted odds ratio 0.50, 95% confidence interval 0.39 to 0.63), as was the multiple birth rate (3/181 (2%) v 84/285 (29%)) (0.04, 0.01 to 0.12). An additional frozen single embryo transfer, however, resulted in a cumulative live birth rate not significantly lower than the rate after one fresh double embryo transfer (132/350 (38%) v 149/353 (42%) (0.85, 0.62 to 1.15), with a minimal cumulative risk of multiple birth (1/132 (1%) v 47/149 (32%)). The odds of a term singleton birth (that is, over 37 weeks) after elective single embryo transfer was almost five times higher than the odds after double embryo transfer (4.93, 2.98 to 8.18).

CONCLUSIONS

Elective single embryo transfer results in a higher chance of delivering a term singleton live birth compared with double embryo transfer. Although this strategy yields a lower pregnancy rate than a double embryo transfer in a fresh IVF cycle, this difference is almost completely overcome by an additional frozen single embryo transfer cycle. The multiple pregnancy rate after elective single embryo transfer is comparable with that observed in spontaneous pregnancies.

The effect of a multifaceted empowerment strategy on decision making about the number of embryos transferred in in vitro fertilisation: randomised controlled trial

OBJECTIVE

To evaluate the effects of a multifaceted empowerment strategy on the actual use of single embryo transfer after in vitro fertilisation.

DESIGN

Randomised controlled trial.

SETTING

Five in vitro fertilisation clinics in the Netherlands.

PARTICIPANTS

308 couples (women aged <40) on the waiting list for a first in vitro fertilisation cycle.

INTERVENTIONS

The multifaceted strategy aimed to empower couples in deciding how many embryos should be transferred. The strategy consisted of a decision aid, support of a nurse specialising in in vitro fertilisation, and the offer of reimbursement by way of an extra treatment cycle. The control group received standard care for in vitro fertilisation.

MAIN OUTCOME MEASURES

Use of single embryo transfer in the first and second treatment cycles as well as decision making variables and costs of the empowerment strategy.

RESULTS

After the first treatment cycle, single embryo transfer was used by 43% (65/152) of couples in the intervention group and 32% (50/156) in the control group (difference 11%, 95% confidence interval 0% to 22%; P=0.05). After the second treatment cycle, single embryo transfer was used by 26% (14/154) of couples in the intervention group compared with 16% (8/51) in the control group (difference 10%, -6% to 26%; P=0.20). Compared with couples receiving standard care, those receiving the empowerment strategy had significantly higher empowerment and knowledge levels but no differences in anxiety levels. Mean total savings per couple in the intervention group were calculated to be €169.75 (£146.77; $219.12).

CONCLUSIONS

A multifaceted empowerment strategy encouraged use of single embryo transfer, increased patients' knowledge, reduced costs, and had no effect on levels of anxiety or depression. This strategy could therefore be an important tool to reduce the twin pregnancy rate after in vitro fertilisation. This trial did not, however, demonstrate the anticipated 25% difference in use of single embryo transfer of the power calculation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00315029.

Infant outcomes of assisted reproduction

Assisted reproductive technologies (ART) have become widely used in the treatment of subfertility over the last 30 years. Currently 1.7% of all births in the UK occur after assisted conception. This review summarises work that has been undertaken to investigate health outcomes of these children and summarises areas where uncertainty continues to exist. Much of the adverse health outcomes of children born after ART are related to higher order birth; however evidence suggests adverse perinatal outcomes in singletons as well as twins and triplets. The cause of adverse health outcomes in ART conceived children is as yet unclear and studies investigating causal factors such as underlying subfertility are discussed.

Guidelines on number of embryos transferred

Based on American Society for Reproductive Medicine (ASRM) and Society for Assisted Reproductive Technology data available in 2007, ASRM's guidelines for the number of embryos to be transferred in in vitro fertilization cycles have been further refined in continuing efforts to reduce the number of higher-order multiple pregnancies. This version replaces the document of the same name that was published most recently in November 2008.