ESHRE good practice recommendations on recurrent implantation failure

STUDY QUESTION

How should recurrent implantation failure (RIF) in patients undergoing ART be defined and managed?

SUMMARY ANSWER

This is the first ESHRE good practice recommendations paper providing a definition for RIF together with recommendations on how to investigate causes and contributing factors, and how to improve the chances of a pregnancy.

WHAT IS KNOWN ALREADY

RIF is a challenge in the ART clinic, with a multitude of investigations and interventions offered and applied in clinical practice, often without biological rationale or with unequivocal evidence of benefit.

STUDY DESIGN SIZE DURATION

This document was developed according to a predefined methodology for ESHRE good practice recommendations. Recommendations are supported by data from the literature, if available, and the results of a previously published survey on clinical practice in RIF and the expertise of the working group. A literature search was performed in PubMed and Cochrane focussing on 'recurrent reproductive failure', 'recurrent implantation failure', and 'repeated implantation failure'.

PARTICIPANTS/MATERIALS SETTING METHODS

The ESHRE Working Group on Recurrent Implantation Failure included eight members representing the ESHRE Special Interest Groups for Implantation and Early Pregnancy, Reproductive Endocrinology, and Embryology, with an independent chair and an expert in statistics. The recommendations for clinical practice were formulated based on the expert opinion of the working group, while taking into consideration the published data and results of the survey on uptake in clinical practice. The draft document was then open to ESHRE members for online peer review and was revised in light of the comments received.

MAIN RESULTS AND THE ROLE OF CHANCE

The working group recommends considering RIF as a secondary phenomenon of ART, as it can only be observed in patients undergoing IVF, and that the following description of RIF be adopted: 'RIF describes the scenario in which the transfer of embryos considered to be viable has failed to result in a positive pregnancy test sufficiently often in a specific patient to warrant consideration of further investigations and/or interventions'. It was agreed that the recommended threshold for the cumulative predicted chance of implantation to identify RIF for the purposes of initiating further investigation is 60%. When a couple have not had a successful implantation by a certain number of embryo transfers and the cumulative predicted chance of implantation associated with that number is greater than 60%, then they should be counselled on further investigation and/or treatment options. This term defines clinical RIF for which further actions should be considered. Nineteen recommendations were formulated on investigations when RIF is suspected, and 13 on interventions. Recommendations were colour-coded based on whether the investigations/interventions were recommended (green), to be considered (orange), or not recommended, i.e. not to be offered routinely (red).

LIMITATIONS REASONS FOR CAUTION

While awaiting the results of further studies and trials, the ESHRE Working Group on Recurrent Implantation Failure recommends identifying RIF based on the chance of successful implantation for the individual patient or couple and to restrict investigations and treatments to those supported by a clear rationale and data indicating their likely benefit.

WIDER IMPLICATIONS OF THE FINDINGS

This article provides not only good practice advice but also highlights the investigations and interventions that need further research. This research, when well-conducted, will be key to making progress in the clinical management of RIF.

STUDY FUNDING/COMPETING INTERESTS

The meetings and technical support for this project were funded by ESHRE. N.M. declared consulting fees from ArtPRED (The Netherlands) and Freya Biosciences (Denmark); Honoraria for lectures from Gedeon Richter, Merck, Abbott, and IBSA; being co-founder of Verso Biosense. He is Co-Chief Editor of Reproductive Biomedicine Online (RBMO). D.C. declared being an Associate Editor of Human Reproduction Update, and declared honoraria for lectures from Merck, Organon, IBSA, and Fairtility; support for attending meetings from Cooper Surgical, Fujifilm Irvine Scientific. G.G. declared that he or his institution received financial or non-financial support for research, lectures, workshops, advisory roles, or travelling from Ferring, Merck, Gedeon-Richter, PregLem, Abbott, Vifor, Organon, MSD, Coopersurgical, ObsEVA, and ReprodWissen. He is an Editor of the journals Archives of Obstetrics and Gynecology and Reproductive Biomedicine Online, and Editor in Chief of Journal Gynäkologische Endokrinologie. He is involved in guideline developments and quality control on national and international level. G.L. declared he or his institution received honoraria for lectures from Merck, Ferring, Vianex/Organon, and MSD. He is an Associate Editor of Human Reproduction Update, immediate past Coordinator of Special Interest Group for Reproductive Endocrinology of ESHRE and has been involved in Guideline Development Groups of ESHRE and national fertility authorities. D.J.M. declared being an Associate Editor for Human Reproduction Open and statistical Advisor for Reproductive Biomedicine Online. B.T. declared being shareholder of Reprognostics and she or her institution received financial or non-financial support for research, clinical trials, lectures, workshops, advisory roles or travelling from support for attending meetings from Ferring, MSD, Exeltis, Merck Serono, Bayer, Teva, Theramex and Novartis, Astropharm, Ferring. The other authors had nothing to disclose.

DISCLAIMER

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

Myocardial infarction risk is increased by periodontal pathobionts: a cross-sectional study

To establish the role of periodontal pathobionts as a risk factor for myocardial infarction, we examined the contribution of five periodontal pathobionts and their virulence genes' expressions to myocardial injury (Troponin-I) and coronary artery disease burden (SYNTAX-I scores) using hierarchical linear regression. Pathobiont loads in subgingival-plaques and intra-coronary-thrombi were compared. Troponin-I release increased with one 16S rRNA gene copy/ng DNA of Porphyromonas gingivalis (β = 6.8 × 10^-6, 95% CI = 1.1 × 10^-7-2.1 × 10^-5), one-fold increased expressions of fimA (β = 14.3, 95% CI = 1.5-27.1), bioF-3 (β = 7.8, 95% CI = 1.1-12.3), prtH (β = 1107.8, 95% CI = 235.6-2451.3), prtP (β = 6772.8, 95% CI = 2418.7-11,126.9), ltxA (β = 1811.8, 95% CI = 217.1-3840.8), cdtB (β = 568.3, 95% CI = 113.4-1250.1), all p < 0.05. SYNTAX-I score increased with one 16S rRNA gene copy/ng DNA of Porphyromonas gingivalis (β = 3.8 × 10^-9, 95% CI = 3.6 × 10^-10-1.8 × 10^-8), one-fold increased expressions of fimA (β = 1.2, 95% CI = 1.1-2.1), bioF-3 (β = 1.1, 95% CI = 1-5.2), prtP (β = 3, 95% CI = 1.3-4.6), ltxA (β = 1.5, 95% CI = 1.2-2.5), all p < 0.05. Within-subject Porphyromonas gingivalis and Tannerella forsythia from intra-coronary-thrombi and subgingival-plaques correlated (rho = 0.6, p < 0.05). Higher pathobiont load and/or upregulated virulence are risk factors for myocardial infarction.Trial registration: ClinicalTrials.gov Identifier: NCT04719026.

O-073 Perinatal outcomes of infants conceived using partner versus donor sperm - An analysis of singleton and twin pregnancies from the UK national dataset

Study question

Are perinatal outcomes different in pregnancies conceived using donor sperm compared with those with partner sperm?

Summary answer

The perinatal outcomes of singleton and twin pregnancies conceived with donor sperm are better when compared to those conceived with partner sperm

What is known already

There has been a substantial increase in the use of donor sperm in the last 15 years across the world. A recent systematic review and meta-analysis has suggested that there is an increased risk of hypertensive disorders of pregnancy and small for gestational age babies from ART treatment using donor sperm compared to partner`s sperm. This meta-analysis was limited due to poor quality of primary studies often with small sample sizes.

Study design, size, duration

This is a retrospective cohort study on 196,293 singleton and 46,275 twin pregnancies from the Human Fertilisation and Embryology Authority (HFEA) anonymised dataset including all live births from 1991 to 2016. Outcomes were preterm birth ( &lt; 37 weeks); very preterm birth ( &lt; 32 weeks); very low, low, high and very high birth weight ( &lt; 1500g, &lt; 2500g, &gt;4000g and &gt;4500g respectively); congenital anomaly and healthy baby (term live birth with appropriate weight and no congenital anomaly).

Participants/materials, setting, methods

All pregnancies resulting in singleton or twin livebirth were included. Any cycle involving donor oocytes, PGD, gamete intra-fallopian transfer, ectopic pregnancy, miscarriage, stillbirth, or termination was excluded. Logistic regression and generalised estimating equations were used for analysis of singletons and twins, respectively. Odds ratios (aOR) with 95% confidence intervals (CI) for donor versus partner sperm were adjusted for maternal age, previous pregnancy, cause of infertility and year for all outcomes plus gestational age for birthweight.

Main results and the role of chance

Baseline characteristics for donor and partner sperm pregnancies were assessed for singleton and twin livebirths separately. In both analyses there were significant differences between donor and partner sperm pregnancies in terms of maternal age, previous pregnancy status and cause of infertility.

Analysis of singleton births demonstrated an increased odds (aOR, 95% CI) of having a healthy baby (1.09, 1.05 - 1.12) and reduced odds of congenital anomaly (0.34, 0.29 - 0.39), very preterm birth (0.66, 0.58-0.75), preterm birth (0.81, 0.76-0.86), low birthweight 0.89 (0.83 - 0.96) in singleton births using donor sperm compared with those using partner sperm. There was, however, an increased odds of high birthweight (1.10, 1.05 - 1.16) and very high birthweight (1.16, 1.05-1.29) with donor sperm pregnancies.

Analysis of twin births conceived with donor sperm also showed higher odds of having a healthy baby (1.07, 1.01 - 1.15) and lower odds of congenital anomaly (0.52, 0.39 - 0.68) compared with partner sperm. There were no statistically significant differences between the birthweight or birth gestation outcomes for twin pregnancies.

Sensitivity analysis of only cases with complete outcome data showed no significant differences when compared to the primary analysis.

Limitations, reasons for caution

This is a retrospective study of a single nation’s routinely collected data. We could not adjust for confounders such as smoking, BMI and pregnancy complications such as pre-eclampsia, as they are not recorded in HFEA’s dataset.

Wider implications of the findings

Patients and clinicians can be reassured that donor sperm pregnancies are not at higher risk of adverse perinatal outcomes. In fact, they are more likely to result in a healthy baby. Worldwide registries should consider including maternal data to enable a better assessment of outcomes.

Trial registration number

Not applicable

O40 Predictive models of individual risk of elective caesarean section complications: a systematic review

Introduction

With increasing caesarean section (c-section) rates, personalised communication of risk has become paramount. A reliable tool to predict complications would support evidence-based discussion around planned mode of birth.

Method

MEDLINE, Embase, Web of Science, CINAHL, and the Cochrane Library were searched on 27th January with the terms relating to c-section, prognostic models, and complications such as infection. Any study developing and/or validating a prognostic model for maternal complications of c-section in the English language after January 1995 was included. Data extracted encompassed: source of data, participant criteria, outcome to be predicted, candidate predictors, actual predictors, sample size, model development, and model performance. PROBAST (Prediction model Risk Of Bias Assessment Tool) was utilised for risk of bias analysis and applicability concern in the prognostic model studies.

Result

7,752 studies were identified, of which 16 were reviewed producing 3 studies where 3 prognostic models were identified which predicted risk of: blood transfusion, spinal hypotension, and postpartum haemorrhage. From the 3 studies, a total of 29 unique candidate predictors were identified and 15 predictors in the final model. Study authors deemed their studies to be exploratory, exploratory, and confirmatory respectively. None were externally validated and all had a high risk of bias due to analysis technique.

Conclusion

Few models have been developed to predict complications of elective c-section. Existing models predicting blood transfusion, spinal hypotension, and postpartum haemorrhage cannot be recommended for clinical practice. Future research should focus on identifying predictors known before surgery and validating resulting models.

Take-home Message

Systematic review of prediction models for planned C-section complications found none suitable for practice.

Cumulative live birth rates following blastocyst- versus cleavage-stage embryo transfer in the first complete cycle of IVF: a population-based retrospective cohort study

STUDY QUESTION

Is there a difference in the odds of a live birth following blastocyst- versus cleavage-stage embryo transfer in the first complete cycle of IVF?

SUMMARY ANSWER

After adjusting for indication bias, there was not enough evidence to suggest a difference in the odds of live birth following blastocyst- versus cleavage-stage embryo transfer in the first complete cycle of IVF.

WHAT IS KNOWN ALREADY

Replacement of blastocyst-stage embryos has become the dominant practice in IVF but there is uncertainty about whether this technique offers an improved chance of cumulative live birth over all fresh and frozen-thawed embryo transfer attempts associated with a single oocyte retrieval.

STUDY DESIGN, SIZE, DURATION

National population-based retrospective cohort study of 100 610 couples who began their first IVF/ICSI treatment at a licenced UK clinic between 1 January 1999 and 30 July 2010.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data from the Human Fertilisation and Embryology Authority (HFEA) register on IVF/ICSI treatments using autologous gametes between 1999 and 2010 were analysed. The primary outcome was the live birth rate over the first complete cycle of IVF. Cumulative live birth rates (CLBR) were compared for couples who underwent blastocyst and cleavage transfer, and the adjusted odds of live birth over the first complete cycle were estimated for each group using binary logistic regression. This analysis was repeated within groups of female age, oocytes collected and primary versus secondary infertility. Inverse probability of treatment weighting was used to account for the imbalance in couple characteristics between treatment groups.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 94 294 (93.7%) couples had a cleavage-stage embryo transfer while 6316 (6.3%) received blastocysts. Over the first complete cycle of IVF/ICSI (incorporating all fresh and frozen-thawed embryo transfers associated with the first oocyte retrieval), the CLBR was increased in those who underwent blastocyst transfer (56.5%) compared to cleavage-stage embryo transfer (34.8%). However, after accounting for the imbalance between exposures, blastocyst transfer did not significantly influence the odds of live birth over the first complete cycle (adjusted odds ratio: 1.03 (0.96, 1.10)).

LIMITATIONS, REASONS FOR CAUTION

Limitations of our study include the retrospective nature of the HFEA dataset and availability of linked data up until 2010. We were unable to adjust for some confounders, such as smoking status, BMI and embryo quality, as these data are not collected at national level by the HFEA. Similarly, there may be unknown couple, treatment or clinic variables that may influence our results. We were unable to assess the intended stage of embryo transfer for women who did not have an embryo replaced, and therefore excluded them from our study. Perinatal outcomes were not included in our analyses and would be a useful basis for future study.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings show that blastocyst-stage embryo transfer may offer an improved chance of live birth in both the first fresh and the first complete cycle of IVF/ICSI compared to cleavage-stage transfer, even in couples with typically poorer prognoses. Where possible, offering blastocyst transfer to a wider range of couples may increase cumulative success rates.

STUDY FUNDING/COMPETING INTEREST(S)

N.J.C. received a Wolfson Foundation Intercalated Degree Research Fellowship funded by the Wolfson Foundation, through the Royal College of Physicians. This work was supported by a Chief Scientist Office Postdoctoral Training Fellowship in Health Services Research and Health of the Public Research (Ref PDF/12/06) held by D.J.M. The views expressed here are those of the authors and not necessarily those of the Chief Scientist Office or the Wolfson Foundation. The funders did not have any role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; nor in the decision to submit the paper for publication. None of the authors has any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

A systematic review of the quality of clinical prediction models in in vitro fertilisation

STUDY QUESTION

What are the best-quality clinical prediction models in IVF (including ICSI) treatment to inform clinicians and their patients of their chance of success?

SUMMARY ANSWER

The review recommends the McLernon post-treatment model for predicting the cumulative chance of live birth over and up to six complete cycles of IVF.

WHAT IS KNOWN ALREADY

Prediction models in IVF have not found widespread use in routine clinical practice. This could be due to their limited predictive accuracy and clinical utility. A previous systematic review of IVF prediction models, published a decade ago and which has never been updated, did not assess the methodological quality of existing models nor provided recommendations for the best-quality models for use in clinical practice.

STUDY DESIGN, SIZE, DURATION

The electronic databases OVID MEDLINE, OVID EMBASE and Cochrane library were searched systematically for primary articles published from 1978 to January 2019 using search terms on the development and/or validation (internal and external) of models in predicting pregnancy or live birth. No language or any other restrictions were applied.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The PRISMA flowchart was used for the inclusion of studies after screening. All studies reporting on the development and/or validation of IVF prediction models were included. Articles reporting on women who had any treatment elements involving donor eggs or sperm and surrogacy were excluded. The CHARMS checklist was used to extract and critically appraise the methodological quality of the included articles. We evaluated models' performance by assessing their c-statistics and plots of calibration in studies and assessed correct reporting by calculating the percentage of the TRIPOD 22 checklist items met in each study.

MAIN RESULTS AND THE ROLE OF CHANCE

We identified 33 publications reporting on 35 prediction models. Seventeen articles had been published since the last systematic review. The quality of models has improved over time with regard to clinical relevance, methodological rigour and utility. The percentage of TRIPOD score for all included studies ranged from 29 to 95%, and the c-statistics of all externally validated studies ranged between 0.55 and 0.77. Most of the models predicted the chance of pregnancy/live birth for a single fresh cycle. Six models aimed to predict the chance of pregnancy/live birth per individual treatment cycle, and three predicted more clinically relevant outcomes such as cumulative pregnancy/live birth. The McLernon (pre- and post-treatment) models predict the cumulative chance of live birth over multiple complete cycles of IVF per woman where a complete cycle includes all fresh and frozen embryo transfers from the same episode of ovarian stimulation. McLernon models were developed using national UK data and had the highest TRIPOD score, and the post-treatment model performed best on external validation.

LIMITATIONS, REASONS FOR CAUTION

To assess the reporting quality of all included studies, we used the TRIPOD checklist, but many of the earlier IVF prediction models were developed and validated before the formal TRIPOD reporting was published in 2015. It should also be noted that two of the authors of this systematic review are authors of the McLernon model article. However, we feel we have conducted our review and made our recommendations using a fair and transparent systematic approach.

WIDER IMPLICATIONS OF THE FINDINGS

This study provides a comprehensive picture of the evolving quality of IVF prediction models. Clinicians should use the most appropriate model to suit their patients' needs. We recommend the McLernon post-treatment model as a counselling tool to inform couples of their predicted chance of success over and up to six complete cycles. However, it requires further external validation to assess applicability in countries with different IVF practices and policies.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the Elphinstone Scholarship Scheme and the Assisted Reproduction Unit, University of Aberdeen. Both D.J.M. and S.B. are authors of the McLernon model article and S.B. is Editor in Chief of Human Reproduction Open. They have completed and submitted the ICMJE forms for Disclosure of potential Conflicts of Interest. The other co-authors have no conflicts of interest to declare.

REGISTRATION NUMBER

N/A.

Age-related natural fertility outcomes in women over 35 years: a systematic review and individual participant data meta-analysis

STUDY QUESTION

What is the rate of natural conception leading to ongoing pregnancy or livebirth over 6–12 months for infertile women of age ≥35 years?

SUMMARY ANSWER

Natural conception rates were still clinically relevant in women aged 35 years and above and were significantly higher in women with unexplained infertility compared to those with other diagnoses.

WHAT IS KNOWN ALREADY

In recent years, increasing numbers of women have attempted to conceive at a later age, resulting in a commensurate increase in the need for ART. However, there is a lack of data on natural fertility outcomes (i.e. no interventions) in women with increasing age.

STUDY DESIGN, SIZE, DURATION

A systematic review with individual participant data (IPD) meta-analysis was carried out. PubMed, MEDLINE, EMBASE, the Cochrane Library, clinicaltrials.gov were searched until 1 July 2018 including search terms ‘fertility service’, ‘waiting list’, ‘treatment-independent’ and ‘spontaneous conception’. Language restrictions were not imposed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Inclusion criteria were studies (at least partly) reporting on infertile couples with female partner of age ≥35 years who attended fertility services, underwent fertility workup (e.g. history, semen analysis, tubal status and ovulation status) and were exposed to natural conception (e.g. independent of treatment such as IVF, ovulation induction and tubal surgery). Studies that exclusively studied only one infertility diagnosis, without including other women presenting to infertility services for other causes of infertility, were excluded. For studies that met the inclusion criteria, study authors were contacted to provide IPD, after which fertility outcomes for women of age ≥35 years were retrieved. Time to pregnancy or livebirth and the effect of increasing age on fertility outcomes after adjustment for other prognostic factors were analysed. Quality of studies was graded with the Newcastle–Ottawa Scale (non-randomised controlled trials (RCTs)) or the Cochrane Risk of Bias tool (for RCTs).

MAIN RESULTS AND THE ROLE OF CHANCE

We included nine studies (seven cohort studies and two RCTs) (n = 4379 women of at least age 35 years), with the observed composite primary outcome of ongoing pregnancy or livebirth occurring in 429 women (9.8%) over a median follow-up of 5 months (25th to 75th percentile: 2.5–8.5 months). Studies were of moderate to high quality. The probability of natural conception significantly decreased with any diagnosis of infertility, when compared with unexplained infertility. We found non-linear effects of female age and duration of infertility on ongoing pregnancy and tabulated the predicted probabilities for unexplained infertile women aged 35–42 years with either primary or secondary infertility and with a duration of infertility from 1 to 6 years. For a 35-year-old woman with 2 years of primary unexplained infertility, the predicted probability of natural conception leading to ongoing pregnancy or livebirth was 0.15 (95% CI 0.11–0.19) after 6 months and 0.24 (95% CI 0.17–0.30) after 12 months. For a 42-year-old woman, this decreased to 0.08 (95% CI 0.04–0.11) after 6 months and 0.13 (95% CI 0.07–0.18) after 12 months.

LIMITATIONS, REASONS FOR CAUTION

In the studies selected, there were different study designs, recruitment strategies in different centres, protocols and countries and different methods of assessment of infertility. Data were limited for women above the age of 40 years.

WIDER IMPLICATIONS OF THE FINDINGS

Women attending fertility services should be encouraged to pursue natural conception while waiting for treatment to commence and after treatment if it is unsuccessful. Our results may aid in counselling women, and, in particular, for those with unexplained infertility.

STUDY FUNDING/COMPETING INTEREST(S)

S.J.C. received funding from the University of Adelaide Summer Research Scholarship. B.W.M. is supported by a NHMRC Investigator grant (GNT1176437), B.W.M. reports consultancy for ObsEva, Merck, Merck KGaA, iGenomix and Guerbet. B.W.M. reports research support by Merck and Guerbet.

PROSPERO REGISTRATION NUMBER

CRD42018096552.

Predicting the chances of having a baby with or without treatment at different time points in couples with unexplained subfertility

STUDY QUESTION

Can we develop a prediction model that can estimate the chances of conception leading to live birth with and without treatment at different points in time in couples with unexplained subfertility?

SUMMARY ANSWER

Yes, a dynamic model was developed that predicted the probability of conceiving under expectant management and following active treatments (in vitro fertilisation (IVF), intrauterine insemination with ovarian stimulation (IUI + SO), clomiphene) at different points in time since diagnosis.

WHAT IS KNOWN ALREADY

Couples with no identified cause for their subfertility continue to have a realistic chance of conceiving naturally, which makes it difficult for clinicians to decide when to intervene. Previous fertility prediction models have attempted to address this by separately estimating either the chances of natural conception or the chances of conception following certain treatments. These models only make predictions at a single point in time and are therefore inadequate for informing continued decision-making at subsequent consultations.

STUDY DESIGN, SIZE, DURATION

A population-based study of 1316 couples with unexplained subfertility attending a regional clinic between 1998 and 2011.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A dynamic prediction model was developed that estimates the chances of conception within 6 months from the point when a diagnosis of unexplained subfertility was made. These predictions were recomputed each month to provide a dynamic assessment of the individualised chances of conception while taking account of treatment status in each month. Conception must have led to live birth and treatments included clomiphene, IUI + SO, and IVF. Predictions for natural conception were externally validated using a prospective cohort from The Netherlands.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 554 (42%) couples started fertility treatment within 2 years of their first fertility consultation. The natural conception leading to live birth rate was 0.24 natural conceptions per couple per year. Active treatment had a higher chance of conception compared to those who remained under expectant management. This association ranged from weak with clomiphene to strong with IVF [clomiphene, hazard ratio (HR) = 1.42 (95% confidence interval, 1.05 to 1.91); IUI + SO, HR = 2.90 (2.06 to 4.08); IVF, HR = 5.09 (4.04 to 6.40)]. Female age and duration of subfertility were significant predictors, without clear interaction with the relative effect of treatment.

LIMITATIONS, REASONS FOR CAUTION

We were unable to adjust for other potentially important predictors, e.g. measures of ovarian reserve, which were not available in the linked Grampian dataset that may have made predictions more specific. This study was conducted using single centre data meaning that it may not be generalizable to other centres. However, the model performed as well as previous models in reproductive medicine when externally validated using the Dutch cohort.

WIDER IMPLICATIONS OF THE FINDINGS

For the first time, it is possible to estimate the chances of conception following expectant management and different fertility treatments over time in couples with unexplained subfertility. This information will help inform couples and their clinicians of their likely chances of success, which may help manage expectations, not only at diagnostic workup completion but also throughout their fertility journey.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a Chief Scientist Office postdoctoral training fellowship in health services research and health of the public research (ref PDF/12/06). B.W.M. is supported by an NHMRC Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck, and Guerbet. None of the other authors declare any conflicts of interest.

Is IUI with ovarian stimulation effective in couples with unexplained subfertility?

STUDY QUESTION

Does starting IUI with ovarian stimulation (IUI-OS) within 1.5 years after completion of the fertility workup increase ongoing pregnancy rates compared to expectant management in couples with unexplained subfertility?

SUMMARY ANSWER

IUI-OS is associated with higher chances of ongoing pregnancy compared to expectant management in unexplained subfertile couples, specifically those with poor prognoses of natural conception, i.e. <15% over 6 months or <25% over 1 year.

WHAT IS KNOWN ALREADY

IUI-OS is often the first-line treatment for couples with unexplained subfertility. Two randomized controlled trials compared IUI-OS to expectant management using different thresholds for the prognosis of natural conception as inclusion criteria and found conflicting results. A cohort of couples with unexplained subfertility exposed to expectant management and IUI-OS offers an opportunity to determine the chances of conception after both strategies and to evaluate whether the effect of IUI-OS depends on a couple's prognosis of natural conception.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study on couples with unexplained or mild male subfertility who could start IUI-OS at any point after completion of the fertility workup, recruited in seven Dutch centres between January 2002 and February 2004. Decisions regarding treatment were subject to local protocols, the judgement of the clinician and the wishes of the couple. Couples with bilateral tubal occlusion, anovulation or a total motile sperm count <1 × 106 were excluded. Follow up was censored at the start of IVF, after the last IUI cycle or at last contact and truncated at a maximum of 1.5 years after the fertility workup.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The endpoint was time to conception leading to an ongoing pregnancy. We used the sequential Cox approach comparing in each month ongoing pregnancy rates over the next 6 months of couples who started IUI-OS to couples who did not. We calculated the prognosis of natural conception for individual couples, updated this over consecutive failed cycles and evaluated whether prognosis modified the effect of starting IUI-OS. We corrected for known predictors of conception using inverse probability weighting.

MAIN RESULTS AND THE ROLE OF CHANCE

Data from 1896 couples were available. There were 800 couples whom had at least one IUI-OS cycle within 1.5 years post fertility workup of whom 142 couples conceived (rate: 0.50 per couple per year, median follow up 4 months). The median period between fertility workup completion and starting IUI-OS was 6.5 months. Out of 1096 untreated couples, 386 conceived naturally (rate: 0.31 per couple per year, median follow up 7 months). Starting IUI-OS was associated with a higher chance of ongoing pregnancy by a pooled, overall hazard ratio of 1.96 (95% CI: 1.47-2.62) compared to expectant management. The effect of treatment was modified by a couple's prognosis of achieving natural conception (P = 0.01), with poorer prognoses or additional failed natural cycles being associated with a stronger effect of treatment. The predicted 6-month ongoing pregnancy rate for a couple with a prognosis of 25% at completion of the fertility workup over the next six cycles (~40% over 1 year) was 25% (95% CI: 21-28%) for expectant management and 24% (95% CI: 9-36%) when starting IUI-OS directly. For a couple with a prognosis of 15% (25% over 1 year), these predicted rates were 17% (95% CI: 15-19%) for expectant management and 24% (95% CI: 15-32%) for starting IUI-OS.

LIMITATIONS, REASONS FOR CAUTION

The effect estimates are based on a prospective cohort followed up for 1.5 years after completion of the fertility workup. Although we balanced the known predictors of conception between treated and untreated couples using inverse probability weighting, observational data may be subject to residual confounding. The results need to be confirmed in external datasets.

WIDER IMPLICATIONS OF THE FINDINGS

These results explain the discrepancies between previous trials that compared IUI-OS to expectant management, but further studies are required to establish the threshold at which IUI-OS is (cost-)effective.

STUDY FUNDING/COMPETING INTEREST(S)

This study was facilitated by (Grant 945/12/002) from ZonMW, The Netherlands Organization for Health Research and Development, The Hague, The Netherlands. B.W.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck and Guerbet. S.B. reports acting as Editor-in-Chief of HROpen. The other authors have no conflicts of interest.

External validation of a dynamic prediction model for repeated predictions of natural conception over time

STUDY QUESTION

How well does a previously developed dynamic prediction model perform in an external, geographical validation in terms of predicting the chances of natural conception at various points in time?

SUMMARY ANSWER

The dynamic prediction model performs well in an external validation on a Scottish cohort.

WHAT IS KNOWN ALREADY

Prediction models provide information that can aid evidence-based management of unexplained subfertile couples. We developed a dynamic prediction model for natural conception (van Eekelen model) that is able to update predictions of natural conception when couples return to their clinician after a period of unsuccessful expectant management. It is not known how well this model performs in an external population.

STUDY DESIGN, SIZE, DURATION

A record-linked registry study including the long-term follow-up of all couples who were considered unexplained subfertile following a fertility workup at a Scottish fertility clinic between 1998 and 2011. Couples with anovulation, uni/bilateral tubal occlusion, mild/severe endometriosis or impaired semen quality according to World Health Organization criteria were excluded.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The endpoint was time to natural conception, leading to an ongoing pregnancy (defined as reaching a gestational age of at least 12 weeks). Follow-up was censored at the start of treatment, at the change of partner or at the end of study (31 March 2012). The performance of the van Eekelen model was evaluated in terms of calibration and discrimination at various points in time. Additionally, we assessed the clinical utility of the model in terms of the range of the calculated predictions.

MAIN RESULTS AND THE ROLE OF CHANCE

Of a total of 1203 couples with a median follow-up of 1 year and 3 months after the fertility workup, 398 (33%) couples conceived naturally leading to an ongoing pregnancy. Using the dynamic prediction model, the mean probability of natural conception over the course of the first year after the fertility workup was estimated at 25% (observed: 23%). After 0.5, 1 and 1.5 years of expectant management after the completion of the fertility workup, the average probability of conceiving naturally over the next year was estimated at 18% (observed: 15%), 14% (observed: 14%) and 12% (observed: 12%). Calibration plots showed good agreement between predicted chances and the observed fraction of ongoing pregnancy within risk groups. Discrimination was moderate with c statistics similar to those in the internal validation, ranging from 0.60 to 0.64. The range of predicted chances was sufficiently wide to distinguish between couples having a good and poor prognosis with a minimum of zero at all times and a maximum of 55% over the first year after the workup, which decreased to maxima of 43% after 0.5 years, 34% after 1 year and 29% after 1.5 years after the fertility workup.

LIMITATIONS, REASONS FOR CAUTION

The model slightly overestimated the chances of conception by ~2-3% points on group level in the first-year post-fertility workup and after 0.5 years of expectant management, respectively. This is likely attributable to the fact that the exact dates of completion of the fertility workup for couples were missing and had to be estimated.

WIDER IMPLICATIONS OF THE FINDINGS

The van Eekelen model is a valid and robust tool that is ready to use in clinical practice to counsel couples with unexplained subfertility on their individualized chances of natural conception at various points in time, notably when couples return to the clinic after a period of unsuccessful expectant management.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a Chief Scientist Office postdoctoral training fellowship in health services research and health of the public research (ref PDF/12/06). There are no conflicts of interest.

IVF for unexplained subfertility; whom should we treat?

STUDY QUESTION

Which couples with unexplained subfertility can expect increased chances of ongoing pregnancy with IVF compared to expectant management?

SUMMARY ANSWER

For couples in which the woman is under 40 years of age, IVF is associated with higher chances of conception than expectant management.

WHAT IS KNOWN ALREADY

The clinical indications for IVF have expanded over time from bilateral tubal blockage to include unexplained subfertility in which there is no identifiable barrier to conception. Yet, there is little evidence from randomized controlled trials that IVF is effective in these couples.

STUDY DESIGN, SIZE, DURATION

We compared outcomes in British couples with unexplained subfertility undergoing IVF (n = 40 921) from registry data to couples with the same type of subfertility on expectant management. Those couples on expectant management (defined as no intervention aside from the advice to have intercourse) comprised a prospective nation-wide Dutch cohort (n = 4875) and a retrospective regional cohort from Aberdeen, Scotland (n = 975). We excluded couples who had tried for <1 year to conceive and also those with anovulation, uni- or bilateral tubal occlusion, mild or severe endometriosis or male subfertility i.e. impaired semen quality according to World Health Organization criteria.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We matched couples who received IVF and couples on expectant management based on their characteristics to control for confounding. We fitted a Cox proportional hazards model including patient characteristics, IVF treatment and their interactions to estimate the individualized chance of conception over 1 year—either following IVF or expectant management for all combinations of patient characteristics. The endpoint was conception leading to ongoing pregnancy, defined as a foetus reaching a gestational age of at least 12 weeks.

MAIN RESULTS AND THE ROLE OF CHANCE

The adjusted 1-year chance of conception was 47.9% (95% CI: 45.0–50.9) after IVF and 26.1% (95% CI: 24.2–28.0) after expectant management. The absolute difference in the average adjusted 1-year chances of conception was 21.8% (95%CI: 18.3–25.3) in favour of IVF. The effectiveness of IVF was influenced by female age, duration of subfertility and previous pregnancy. IVF was effective in women under 40 years, but the 1-year chance of an IVF conception declined sharply in women over 34 years. In contrast, in woman over 40 years of age, IVF was less effective, with an absolute difference in chance compared to expectant management of 10% or lower. Regardless of female age, IVF was also less effective in couples with a short period of secondary subfertility (1 year) who had chances of natural conception of 30% or above.

LIMITATIONS, REASONS FOR CAUTION

The 1-year chances of conception were based on three cohorts with different sampling mechanisms. Despite adjustment for the three most important prognostic patient characteristics, namely female age, duration of subfertility and primary or secondary subfertility, our estimates might not be free from residual confounding.

WIDER IMPLICATIONS OF THE FINDINGS

IVF should be used selectively based on judgements on gain compared to continuing expectant management for a given couple. Our results can be used by clinicians to counsel couples with unexplained subfertility, to inform their expectations and facilitate evidence-based, shared decision making.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by Tenovus Scotland [grant G17.04]. Travel for RvE was supported by the Amsterdam Reproduction & Development Research Group [grant V.000296]. SB reports acting as editor-in-chief of HROpen. Other authors have no conflicts.

Predicting the cumulative chance of live birth over multiple complete cycles of in vitro fertilization: an external validation study

STUDY QUESTION

Are the published pre-treatment and post-treatment McLernon models, predicting cumulative live birth rates (LBR) over multiple complete IVF cycles, valid in a different context?

SUMMARY ANSWER

With minor recalibration of the pre-treatment model, both McLernon models accurately predict cumulative LBR in a different geographical context and a more recent time period.

WHAT IS KNOWN ALREADY

Previous IVF prediction models have estimated the chance of a live birth after a single fresh embryo transfer, thereby excluding the important contribution of embryo cryopreservation and subsequent IVF cycles to cumulative LBR. In contrast, the recently developed McLernon models predict the cumulative chance of a live birth over multiple complete IVF cycles at two certain time points: (i) before initiating treatment using baseline characteristics (pre-treatment model) and (ii) after the first IVF cycle adding treatment related information to update predictions (post-treatment model). Before implementation of these models in clinical practice, their predictive performance needs to be validated in an independent cohort.

STUDY DESIGN, SIZE, DURATION

External validation study in an independent prospective cohort of 1515 Dutch women who participated in the OPTIMIST study (NTR2657) and underwent their first IVF treatment between 2011 and 2014. Participants underwent a total of 2881 complete treatment cycles, with a complete cycle defined as all fresh and frozen thawed embryo transfers resulting from one episode of ovarian stimulation. The follow up duration was 18 months after inclusion, and the primary outcome was ongoing pregnancy leading to live birth.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Model performance was externally validated up to three complete treatment cycles, using the linear predictor as described by McLernon et al. to calculate the probability of a live birth. Discrimination was expressed by the c-statistic and calibration was depicted graphically in a calibration plot. In contrast to the original model development cohort, anti-Müllerian hormone (AMH), antral follicle count (AFC) and body weight were available in the OPTIMIST cohort, and evaluated as potential additional predictors for model improvement.

MAIN RESULTS AND THE ROLE OF CHANCE

Applying the McLernon models to the OPTIMIST cohort, the c-statistic of the pre-treatment model was 0.62 (95% CI: 0.59-0.64) and of the post-treatment model 0.71 (95% CI: 0.69-0.74). The calibration plot of the pre-treatment model indicated a slight overestimation of the cumulative LBR. To improve calibration, the pre-treatment model was recalibrated by subtracting 0.35 from the intercept. The post-treatment model calibration plot revealed accurate cumulative LBR predictions. After addition of AMH, AFC and body weight to the McLernon models, the c-statistic of the updated pre-treatment model improved slightly to 0.66 (95% CI: 0.64-0.68), and of the updated post-treatment model remained at the previous level of 0.71 (95% CI: 0.69-0.73). Using the recalibrated pre-treatment model, a woman aged 30 years with 2 years of primary infertility who starts ICSI treatment for male factor infertility has a chance of 40% of a live birth from the first complete cycle, increasing to 72% over three complete cycles. If this woman weighs 70 kg, has an AMH of 1.5 ng/mL and an AFC of 10 measured at the beginning of her treatment, the updated pre-treatment model revises the estimated chance of a live birth to 30% in the first complete cycle and 59% over three complete cycles. If this woman then has five retrieved oocytes, no embryos cryopreserved and a single fresh cleavage stage embryo transfer in her first ICSI cycle, the post-treatment model estimates the chances of a live birth at 28 and 58%, respectively.

LIMITATIONS, REASONS FOR CAUTION

Two randomized controlled trials (RCT) evaluating the effectiveness of gonadotropin dose individualization on basis of the AFC were nested within the OPTIMIST study. The strict dosing regimens, the RCT in- and exclusion criteria and the limited follow up time of 18 months might have influenced model performance in this independent cohort. Also, consistent with the original model development study, external validation was performed using the optimistic assumption that the cumulative LBR in couples who discontinue treatment without a live birth would have been equal to that of those who continue treatment.

WIDER IMPLICATIONS OF THE FINDINGS

After national recalibration to account for geographical differences in IVF treatment, the McLernon prediction models can be introduced as new counselling tools in clinical practice to inform patients and to complement clinical reasoning. These models are the first to offer an objective and personalized estimate of the cumulative probability of a live birth over multiple complete IVF cycles.

STUDY FUNDING/COMPETING INTEREST(S)

No external funds were obtained for this study. M.J.C.E., D.J.M. and S.B. have nothing to disclose. J.A.L, S.C.O, T.C.v.T. and H.LT. received an unrestricted personal grant from Merck BV. B.W.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for ObsEva, Merck and Guerbet. F.J.M.B. receives monetary compensation as a member of the external advisory board for Merck BV (the Netherlands) and Ferring pharmaceutics BV (the Netherlands), for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics on automated AMH assay development, and for a research cooperation with Ansh Labs (USA).

TRIAL REGISTRATION NUMBER

Not applicable.

Predicting the chance of live birth for women undergoing IVF: a novel pretreatment counselling tool

STUDY QUESTION

Which pretreatment patient variables have an effect on live birth rates following assisted conception?

SUMMARY ANSWER

The predictors in the final multivariate logistic regression model found to be significantly associated with reduced chances of IVF/ICSI success were increasing age (particularly above 36 years), tubal factor infertility, unexplained infertility and Asian or Black ethnicity.

WHAT IS KNOWN ALREADY

The two most widely recognized prediction models for live birth following IVF were developed on data from 1991 to 2007; pre-dating significant changes in clinical practice. These existing IVF outcome prediction models do not incorporate key pretreatment predictors, such as BMI, ethnicity and ovarian reserve, which are readily available now.

STUDY DESIGN, SIZE, DURATION

In this cohort study a model to predict live birth was derived using data collected from 9915 women who underwent IVF/ICSI treatment at any CARE (Centres for Assisted Reproduction) clinic from 2008 to 2012. Model validation was performed on data collected from 2723 women who underwent treatment in 2013. The primary outcome for the model was live birth, which was defined as any birth event in which at least one baby was born alive and survived for more than 1 month.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data were collected from 12 fertility clinics within the CARE consortium in the UK. Multivariable logistic regression was used to develop the model. Discriminatory ability was assessed using the area under receiver operating characteristic (AUROC) curve, and calibration was assessed using calibration-in-the-large and the calibration slope test.

MAIN RESULTS AND THE ROLE OF CHANCE

The predictors in the final model were female age, BMI, ethnicity, antral follicle count (AFC), previous live birth, previous miscarriage, cause and duration of infertility. Upon assessing predictive ability, the AUROC curve for the final model and validation cohort was (0.62; 95% confidence interval (CI) 0.61-0.63) and (0.62; 95% CI 0.60-0.64) respectively. Calibration-in-the-large showed a systematic over-estimation of the predicted probability of live birth (Intercept (95% CI) = -0.168 (-0.252 to -0.084), P < 0.001). However, the calibration slope test was not significant (slope (95% CI) = 1.129 (0.893-1.365), P = 0.28). Due to the calibration-in-the-large test being significant we recalibrated the final model. The recalibrated model showed a much-improved calibration.

LIMITATIONS, REASONS FOR CAUTION

Our model is unable to account for factors such as smoking and alcohol that can affect IVF/ICSI outcome and is somewhat restricted to representing the ethnic distribution and outcomes for the UK population only. We were unable to account for socioeconomic status and it may be that by having 75% of the population paying privately for their treatment, the results cannot be generalized to people of all socioeconomic backgrounds. In addition, patients and clinicians should understand this model is designed for use before treatment begins and does not include variables that become available (oocyte, embryo and endometrial) as treatment progresses. Finally, this model is also limited to use prior to first cycle only.

WIDER IMPLICATIONS OF THE FINDINGS

To our knowledge, this is the first study to present a novel, up-to-date model encompassing three readily available prognostic factors; female BMI, ovarian reserve and ethnicity, which have not previously been used in prediction models for IVF outcome. Following geographical validation, the model can be used to build a user-friendly interface to aid decision-making for couples and their clinicians. Thereafter, a feasibility study of its implementation could focus on patient acceptability and quality of decision-making.

STUDY FUNDING/COMPETING INTEREST

None.

Validation of a short questionnaire for estimating dietary calcium intakes

Concern about calcium supplements, and mainly minor side effects (e.g. constipation) impacting on compliance, means that assessing dietary calcium intake is important. There is no suitable biomarker. Compared to food diaries, a short questionnaire was an efficient way of confirming that patients had adequate calcium intakes (>700 or >1,000 mg)

INTRODUCTION

Calcium is usually given alongside treatments for osteoporosis, but recent concerns about potential side effects have led to questioning whether supplements are always necessary. It is difficult to assess calcium intake in a clinical setting and be certain that the patient is getting enough calcium. The aim of this study was to determine whether a short questionnaire for estimating dietary calcium intakes in a clinical setting was fit for purpose.

METHODS

We assessed dietary calcium intakes using a short questionnaire (CaQ) in patients attending an osteoporosis clinic (n = 117) and compared them with calcium intakes obtained from a 7-day food diary (n = 72) and a food frequency questionnaire (FFQ) (n = 33).

RESULTS

Mean (SD) daily calcium intakes from the CaQ were 836 (348) mg; from the diaries, 949 (384) mg; and from the FFQ, 1,141 (387) mg. The positive predictive value (PPV) was >80% for calcium cut-offs > 700 mg and 70% for cut-offs > 1,000 mg. The calcium intakes for the false positives results were not far below the cut-off. For 1,200 mg, the PPV was 67% or less.

CONCLUSION

The CaQ is an adequate tool for assessing whether a patient has daily calcium intakes above 700 or 1,000 mg; if below these cut-offs, it is possible that the patient still has enough calcium in the diet, which could be clarified by questioning the patient further. As there were few patients with calcium intakes above 1,200 mg a day, the CaQ cannot be recommended as a tool for confirming higher dietary calcium intakes.

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.

Randomized controlled trial of intubation with the McGrath Series 5 videolaryngoscope by inexperienced anaesthetists

BACKGROUND

The McGrath Series 5 videolaryngoscope might reduce the incidence of unexpected difficult tracheal intubation. If it also performs as well as a standard laryngoscope during uncomplicated intubations, there would be an argument for the McGrath to become the laryngoscope of choice in higher risk settings, such as rapid sequence induction by inexperienced anaesthetists. Therefore, we compared the McGrath and the Macintosh laryngoscopes during routine tracheal intubation performed by inexperienced anaesthetists.

METHODS

Single-blind randomized controlled trial with 120 adult patients allocated to intubation by first-year anaesthetic trainees, using a McGrath or Macintosh laryngoscope. The primary outcome was time to intubation. Secondary outcomes were quality of view at laryngoscopy and evidence of differential learning between using the two laryngoscopes. A Cox proportional hazards model was used to determine the effect of the laryngoscopes on time to intubation.

RESULTS

Duration of intubation was significantly longer (P<0.001) in the McGrath group [median (IQR); 47.0 (39.0-60.0) vs 29.5 (23.0-36.8) s]. There were no significant differences in other outcomes, including grade of laryngoscopy view, visual confirmation of tube placement, number of laryngoscopies, or complications (oesophageal intubation, hypoxaemia, and airway trauma). There was no differential learning effect.

CONCLUSIONS

There were no advantages to using the McGrath laryngoscope for uncomplicated tracheal intubation and duration of intubation was longer, so it should not be used as a first-line laryngoscope instrument by inexperienced anaesthetists.

A study of the safety of current gastrointestinal endoscopy (EGD)

BACKGROUND AND STUDY AIMS

Previous attempts at assessing the safety of upper gastrointestinal endoscopy have been hampered by incomplete data collection. We aimed to assess the 30-day mortality associated with esophagogastroduodenoscopy (EGD) and assess the important risk factors.

PATIENTS AND METHODS

A retrospective cohort study was conducted of patients who underwent endoscopy at Ninewells Hospital in Dundee between 1 June 2000 and 31 May 2003. A total of 11 501 EGDs were performed in 8926 patients. These patients were record-linked to the death registry and the database of hospital admissions in order to calculate the all-cause 30-day mortality. An expert panel judged whether EGD had caused or contributed to the deaths. Logistic regression analysis was performed on outcomes of all-cause and EGD-contributed mortality.

RESULTS

The median age of the patients was 62 years (interquartile range 48 - 74 years), 54 % were women, and 94 % of procedures were diagnostic. A total of 395 patients died within 30 days (all-cause 30-day mortality rate 4.4 %). One patient death was caused directly by the EGD (procedure-caused mortality rate 1 in 9000). EGD was judged to have contributed to patient deaths at a rate of 1 in 182, based on majority agreement of experts: some factors associated with these deaths were percutaneous endoscopic gastrostomy insertion (odds ratio [OR] 18.39, 95 % confidence interval [CI] 5.71 - 59.22), melena or hematemesis indications (OR 9.01, 95 % CI 3.53 - 22.99), and esophageal varices (OR 6.28, 95 % CI 1.54 - 25.60).

CONCLUSIONS

A causal death rate of 1 in 9000 suggests that EGD is very safe. However, certain patient groups have an increased mortality, and the risks and benefits of EGD should be carefully evaluated in each patient.