Search

Researchers interested in causal questions must deal with two sources of error: random error (random deviation from the true mean value of a distribution), and bias (systematic deviance from the true mean value due to extraneous factors). For some causal questions, randomization is not feasible, and observational studies are necessary. Bias poses a substantial threat to the validity of observational research and can have important consequences for health policy developed from the findings. The current piece describes bias and its sources, outlines proposed methods to estimate its impacts in an observational study, and demonstrates how these methods may be used to inform debate on the causal relationship between medically assisted reproduction (MAR) and health outcomes, using cancer as an example. In doing so, we aim to enlighten researchers who work with observational data, especially regarding the health effects of MAR and infertility, on the pitfalls of bias, and how to address them. We hope that, in combination with the provided example, we can convince readers that estimating the impact of bias in causal epidemiologic research is not only important but necessary to inform the development of robust health policy and clinical practice recommendations. [ABSTRACT FROM AUTHOR]

STUDY QUESTION What is the association between a country's level of gender equality and access to ART, as measured through ART utilization? SUMMARY ANSWER ART utilization is associated with a country's level of gender equality even after controlling for the level of development. WHAT IS KNOWN ALREADY Although gender equality is recognized as an important determinant of population health, its association with fertility care, a highly gendered condition, has not been explored. STUDY DESIGN, SIZE, DURATION A longitudinal cross-national analysis of ART utilization in 69 countries during 2002–2014 was carried out. PARTICPANTS/MATERIALS, SETTING, METHODS The Gender Inequality Index (GII), Human Development Index (HDI), and their component indicators were modelled against ART utilization using univariate regression models as well as mixed-effects regression methods (adjusted for country, time, and economic/human development) with multiple imputation to account for missing data. MAIN RESULTS AND THE ROLE OF CHANCE ART utilization is associated with the GII. In an HDI-adjusted analysis, a one standard deviation decrease in the GII (towards greater equality) is associated with a 59% increase in ART utilization. Gross national income per capita, the maternal mortality ratio, and female parliamentary representation were the index components most predictive of ART utilization. LIMITATIONS, REASONS FOR CAUTION Only ART was used rather than all infertility treatments (including less costly and non-invasive treatments such as ovulation induction). This was a country-level analysis and the results cannot be generalized to smaller groups. Not all modelled variables were available for each country across 2002–2014. WIDER IMPLICATIONS OF THE FINDINGS Access to fertility care is central to women's sexual and reproductive health, to women's rights, and to human rights. As gender equality improves, so does access to ART. This relation is likely to be reinforcing and bi-directional, with progress towards global, equitable access to fertility care also improving women's status and participation in societies. STUDY FUNDING/COMPETING INTEREST(S) External funding was not provided for this study. G.D.A. declares consulting fees from Labcorp and CooperSurgical. G.D.A. is the founder and CEO of Advanced Reproductive Care, Inc. as well as the Chair of the International Committee for Monitoring Assisted Reproductive Technologies (ICMART) and the World Endometriosis Research Foundation, both of which are unpaid roles. G.M.C. is an ICMART Board Representative, which is an unpaid role, and no payments are received from ICMART to UNSW, Sydney, or to G.M.C. to undertake this study. O.F. S.D. F.Z.-H. and E.K. report no conflicts of interest. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Previous studies suggest that children conceived via the use of assisted reproductive technologies (ARTs) are at increased risk for congenital anomalies (CAs). However, underlying infertility was not always accounted for, and fertility treatments have expanded over time. This population-based cohort study examines the risk for CAs in children conceived using various types of fertility treatment, including ARTs, compared with those conceived without the use of fertility treatment among parents with and without a history of infertility. Visual Abstract. The Risk for Congenital Anomalies in Children Conceived With Medically Assisted Fertility Treatment: Previous studies suggest that children conceived via the use of assisted reproductive technologies (ARTs) are at increased risk for congenital anomalies (CAs). However, underlying infertility was not always accounted for, and fertility treatments have expanded over time. This population-based cohort study examines the risk for CAs in children conceived using various types of fertility treatment, including ARTs, compared with those conceived without the use of fertility treatment among parents with and without a history of infertility. Background: More than 2 million children are conceived annually using assisted reproductive technologies (ARTs), with a similar number conceived using ovulation induction and intrauterine insemination (OI/IUI). Previous studies suggest that ART-conceived children are at increased risk for congenital anomalies (CAs). However, the role of underlying infertility in this risk remains unclear, and ART clinical and laboratory practices have changed drastically over time, particularly there has been an increase in intracytoplasmic sperm injection (ICSI) and cryopreservation. Objective: To investigate the role of underlying infertility and fertility treatment on CA risks in the first 2 years of life. Design: Propensity score–weighted population-based cohort study. Setting: New South Wales, Australia. Participants: 851 984 infants (828 099 singletons and 23 885 plural children) delivered between 2009 and 2017. Measurements: Adjusted risk difference (aRD) in CAs of infants conceived through fertility treatment compared with 2 naturally conceived (NC) control groups—those with and without a parental history of infertility (NC-infertile and NC-fertile). Results: The overall incidence of CAs was 459 per 10 000 singleton births and 757 per 10 000 plural births. Compared with NC-fertile singleton control infants (n  = 747 018), ART-conceived singleton infants (n  = 31 256) had an elevated risk for major genitourinary abnormalities (aRD, 19.0 cases per 10 000 births [95% CI, 2.3 to 35.6]); the risk remained unchanged (aRD, 22 cases per 10 000 births [CI, 4.6 to 39.4]) when compared with NC-infertile singleton control infants (n  = 36 251) (that is, after accounting for parental infertility), indicating that ART remained an independent risk. After accounting for parental infertility, ICSI in couples without male infertility was associated with an increased risk for major genitourinary abnormalities (aRD, 47.8 cases per 10 000 singleton births [CI, 12.6 to 83.1]). There was some suggestion of increased risk for CAs after fresh embryo transfer, although estimates were imprecise and inconsistent. There were no increased risks for CAs among OI/IUI-conceived infants (n  = 13 574). Limitations: This study measured the risk for CAs only in those children who were born at or after 20 weeks' gestation. Observational study design precludes causal inference. Many estimates were imprecise. Conclusion: Patients should be counseled on the small increased risk for genitourinary abnormalities after ART, particularly after ICSI, which should be avoided in couples without problems of male infertility. Primary Funding Source: Australian National Health and Medical Research Council. [ABSTRACT FROM AUTHOR]

Study Question: In a country with supportive funding for medically assisted reproduction (MAR) technologies, what is the proportion of MAR births over-time?Summary Answer: In 2017, 6.7% of births were conceived by MAR (4.8% ART and 1.9% ovulation induction (OI)/IUI) with a 55% increase in ART births and a stable contribution from OI/IUI births over the past decade.What Is Known Already: There is considerable global variation in utilization rates of ART despite a similar infertility prevalence worldwide. While the overall contribution of ART to national births is known in many countries because of ART registries, very little is known about the contribution of OI/IUI treatment or the socio-demographic characteristics of the parents. Australia provides supportive public funding for all forms of MAR with no restrictions based on male or female age, and thus provides a unique setting to investigate the contribution of MAR to national births as well as the socio-demographic characteristics of parents across the different types of MAR births.Study Design, Size, Duration: This is a novel population-based birth cohort study of 898 084 births using linked ART registry data and administrative data including birth registrations, medical services, pharmaceuticals, hospital admissions and deaths. Birth (a live or still birth of at least one baby of ≥400 g birthweight or ≥20 weeks' gestation) was the unit of analysis in this study. Multiple births were considered as one birth in our analysis.Participants/materials, Setting, Methods: This study included a total of 898 084 births (606 488 mothers) in New South Wales and the Australian Capital Territory, Australia 2009-2017. We calculated the prevalence of all categories of MAR-conceived births over the study period. Generalized estimating equations were used to examine the association between parental characteristics (parent's age, parity, socio-economic status, maternal country of birth, remoteness of mother's dwelling, pre-existing medical conditions, smoking, etc.) and ART and OI/IUI births relative to naturally conceived births.Main Results and the Role Of Chance: The proportion of MAR births increased from 5.1% of all births in 2009 to 6.7% in 2017, representing a 30% increase over the decade. The proportion of OI/IUI births remained stable at around 2% of all births, representing 32% of all MAR births. Over the study period, ART births conceived by frozen embryo-transfer increased nearly 3-fold. OI/IUI births conceived using clomiphene citrate decreased by 39%, while OI/IUI births conceived using letrozole increased 56-fold. Overall, there was a 55% increase over the study period in the number of ART-conceived births, rising to 56% of births to mothers aged 40 years and older. In 2017, almost one in six births (17.6%) to mothers aged 40 years and over were conceived using ART treatment. Conversely, the proportion of OI/IUI births was similar across different mother's age groups and remained stable over the study period. ART children, but not OI/IUI children, were more likely to have parents who were socio-economically advantaged compared to naturally conceived children. For example, compared to naturally conceived births, ART births were 16% less likely to be born to mothers who live in the disadvantaged neighbourhoods after accounting for other covariates (adjusted relative risk (aRR): 0.84 [95% CI: 0.81-0.88]). ART- or OI/IUI-conceived children were 25% less likely to be born to immigrant mothers than births after natural conception (aRR: 0.75 [0.74-0.77]).Limitations, Reasons For Caution: The social inequalities that we observed between the parents of children born using ART and naturally conceived children may not directly reflect disparities in accessing fertility care for individuals seeking treatment.Wider Implications Of the Findings: With the ubiquitous decline in fertility rates around the world and the increasing trend to delay childbearing, this population-based study enhances our understanding of the contribution of different types of MARs to population profiles among births in high-income countries. The parental socio-demographic characteristics of MAR-conceived children differ significantly from naturally conceived children and this highlights the importance of accounting for such differences in studies investigating the health and development of MAR-conceived children.Study Funding/competing Interest(s): This study was funded through Australian National Health and Medical Research Council (NHMRC) grant: APP1127437. G.M.C. is an employee of The University of New South Wales (UNSW) and Director of the National Perinatal Epidemiology and Statistics Unit (NPESU), UNSW. The NPESU manages the Australian and New Zealand Assisted Reproduction Database with funding support from the Fertility Society of Australia and New Zealand. C.V. is an employee of The University of New South Wales (UNSW), Director of Clinical Research of IVFAustralia, Member of the Board of the Fertility Society of Australia and New Zealand, and Member of Research Committee of School of Women's and Children's Health, UNSW. C.V. reports grants from Australian National Health and Medical Research Council (NHMRC), and Merck KGaA. C.V. reports consulting fees, and payment or honoraria for lectures, presentations, speakers, bureaus, manuscript, writing or educational events or attending meeting or travel from Merck, Merck Sparpe & Dohme, Ferring, Gedon-Richter and Besins outside this submitted work. C.V. reported stock or stock options from Virtus Health Limited outside this submitted work. R.J.N. is an employee of The University of Adelaide, and Chair DSMC for natural therapies trial of The University of Hong Kong. R.J.N. reports grants from NHMRC. R.J.N. reports lecture fees and support for attending or travelling for lecture from Merck Serono which is outside this submitted work. L.R.J. is an employee of The UNSW and Foundation Director of the Centre for Big Data Research in Health at UNSW Sydney. L.R.J. reports grants from NHMRC. The other co-authors have no conflict of interest.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Study Question: What were the utilization, effectiveness and safety of practices in assisted reproductive technologies (ART) globally in 2014 and what global trends could be observed?Summary Answer: The estimated total number of ART cycles conducted in 76 participating countries in 2014 was 1.93 million representing ∼66% of global activity, with 5-year trends including an increase in success rates and proportion of frozen embryo transfer (FET) cycles, improvement in cumulative live birth rates per aspiration, a continued increase in single embryo transfer (SET) and thus a reduction in multiple birth rates, an increase in preimplantation genetic testing and stabilization in the use of intracytoplasmic sperm injection (ICSI).What Is Known Already: ART is widely practiced throughout the world but continues to be characterized by significant disparities in utilization, practice, effectiveness and safety. The International Committee for Monitoring Assisted Reproductive Technologies (ICMART) annual world report series provides an important instrument for tracking trends in ART treatment and for providing clinical and public health data to ART professionals, health authorities, patients and the general public.Study Design, Size, Duration: A retrospective, cross-sectional survey on ART procedures performed globally during 2014 was carried out. A new method for calculating ART utilization rates and number of babies born was introduced in this latest ICMART world report.Participants/materials, Setting, Methods: Overall, 76 countries and 2 746 ART centres submitted data through national and regional ART registries on ART cycles performed during 2014 and their treatment and pregnancy outcomes. ART cycles and outcomes are described at a country level, regionally and globally. Aggregate country data are processed and analyzed based on methods developed by ICMART.Main Results and the Role Of Chance: A total of 1 629 179 ART cycles were reported for the treatment year 2014. After imputing data for missing values and non-reporting centres in reporting countries, an estimated 1 929 905 cycles resulted in >439 039 babies in reporting countries. From 2010 to 2014, the number of reported non-donor aspirations and FET cycles increased by 37.3% and 67.5%, respectively. The proportion of women aged ≥40 years undergoing non-donor ART increased from 23.2% in 2010 to 27.0% in 2014. ICSI, as a percentage of non-donor aspiration cycles, remained relatively stable at 64.8%. The IVF/ICSI combined delivery rates per fresh aspiration and FET cycle were 19.9% and 24.3%, respectively. In fresh non-donor cycles, SET increased from 30.0% in 2010 to 40.0% in 2014, while the average number of transferred embryos decreased from 1.95 to 1.73-but with wide country variation. The rate of twin deliveries following fresh non-donor transfers continued to decrease, from 20.4% in 2010 to 16.2% in 2014, and the triplet rate decreased from 1.1% to 0.5%. In FET non-donor cycles in 2014, the SET rate was 61.6%, with an average of 1.43 embryos transferred, resulting in twin and triplet rates of 10.1% and 0.2%, respectively. The cumulative delivery rate per aspiration increased from 27.1% in 2010 to 32.1% in 2014. The overall perinatal mortality rate per 1 000 births was 19.4 following fresh IVF/ICSI cycles and 9.5 following FET cycles. Among reporting countries, oocyte donation cycles represented 7.3% of all embryo transfers (89 751 transfer cycles) and resulted in 39 278 babies.Limitations, Reasons For Caution: The data presented are dependent on the quality and completeness of data submitted by individual countries to ICMART directly or through regional registries. This report covers approximately two-thirds of world ART activity. China is a major contributor of global cycles missing from this report. Continued efforts to improve the quality and consistency of ART data reported by registries are still needed, including the use of internationally agreed standard definitions (The International Glossary of Infertility and Fertility Care). A new method was introduced in this report to calculate ART utilization and number of babies born following ART; therefore, these results are not directly comparable with previous reports.Wider Implications Of the Findings: The ICMART world reports provide the most comprehensive global statistical census and review of ART utilization, effectiveness, safety and quality. While ART treatment effectiveness and safety continue to increase globally, the wide disparities in access to treatment, procedures performed and embryo transfer practices warrant attention by clinicians and policymakers. The new method for estimating ART utilization and number of babies born provided more conservative estimates compared to the previuos method.Study Funding/competing Interest(s): ICMART receives unrestricted grants from Abbott and Ferring Pharmaceuticals. ICMART also acknowledges financial support from the following organizations: American Society for Reproductive Medicine; Asia Pacific Initiative on Reproduction; European Society of Human Reproduction and Embryology; Fertility Society of Australia and New Zealand; Japan Society for Reproductive Medicine; Japan Society of Fertilization and Implantation; Red Latinoamericana de Reproducción Asistida; and the Society for Assisted Reproductive Technology. S.D. reports industry sponsorship for attendance of conference from Ferring, and research grants to support African Network and Registry of ART from Ferring and Merck outside the submitted work. F.Z.-H. reports lectures at organized webinars for Ferring and Merck. O.I. reports honoraria for consulting from Ferring, Merck and ObsEva, as well as honoraria for lectures from Ferring and Merck. G.M.C., J.d.M., M.B., M.S.K. and G.D.A. have nothing to disclose.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

BACKGROUND Despite the widespread use of assisted reproductive technology (ART), few studies analyse its impact on the total fertility rate (TFR). Furthermore, very little is known about how ART affects fertility at older reproductive ages and contributes to family size. OBJECTIVE We aim to quantify the contribution of ART to total and age-specific fertility rates and in relation to the transition to first and subsequent births in Australia. METHODS Using data from a comprehensive clinical registry of ART treatments, age-specific ART and non-ART fertility rates were calculated and used to decompose the change in the TFR between 2010 and 2017 into ART and non-ART components. RESULTS ART represented an increasing and relevant contribution to the TFR, corresponding to an impact of the order of 4% to 5% per annum, or approximately to 1 in 20 births. Increasing fertility rates at age 33 and above exerted a positive effect on the overall TFR, and they were almost entirely attributable to the increasing use of ART. Women resorted to ART especially to have a first child. [ABSTRACT FROM AUTHOR]

Study Question: What was the utilization, effectiveness and safety of practices in ART globally in 2012 and what global trends could be observed?Summary Answer: The total number of ART cycles increased by almost 20% since 2011 and the main trends were an increase in frozen embryo transfers (FET), oocyte donation, preimplantation genetic testing and single embryo transfers (SET), whereas pregnancy and delivery rates (PR, DR) remained stable, and multiple deliveries decreased.What Is Known Already: ART is widely practiced throughout the world, but continues to be characterized by significant disparities in utilization, availability, practice, effectiveness and safety. The International Committee for Monitoring Assisted Reproductive Technologies (ICMART) annual world report provides a major tool for tracking trends in ART treatment for over 25 years and gives important data to ART professionals, public health authorities, patients and the general public.Study Design, Size, Duration: A retrospective, cross-sectional survey on the utilization, effectiveness and safety of ART procedures performed globally during 2012 was carried out.Participants/materials, Setting, Methods: Sixty-nine countries and 2600 ART clinics submitted data on ART cycles performed during the year 2012, and their pregnancy outcome, through national and regional ART registries. ART cycles and outcomes are described at country, regional and global levels. Aggregate country data were processed and analyzed based on methods developed by ICMART.Main Results and Role Of Chance: A total of 1 149 817 ART cycles were reported for the treatment year 2012. After imputing data for missing values and non-reporting clinics in reporting countries, 1 948 898 cycles (an increase of 18.6% from 2011) resulted in >465 286 babies (+17.9%) in reporting countries. China did not report and is not included in this estimate. The best estimate of global utilization including China is ∼2.8 million cycles and 0.9 million babies. From 2011 to 2012, the number of reported aspirations and FET cycles increased by 6.9% and 16.0%, respectively. The proportion of women aged 40 years or older undergoing non-donor ART increased from 24.0% in 2011 to 25.2% in 2012. ICSI, as a percentage of non-donor aspiration cycles, increased from 66.5% in 2011 to 68.9% in 2012. The IVF/ICSI combined delivery rates per fresh aspiration and FET cycles were 19.8% and 22.1%, respectively. In fresh non-donor cycles, SET increased from 31.4% in 2011 to 33.7% in 2012, while the average number of transferred embryos decreased from 1.91 to 1.88, respectively-but with wide country variation. The rates of twin deliveries following fresh non-donor transfers decreased from 19.6% in 2011 to 18.0% in 2012, and the triplet rate decreased from 0.9% to 0.8%. In FET non-donor cycles, SET was 54.8%, with an average of 1.54 embryos transferred and twin and triplet rates of 11.1% and 0.4%, respectively. The cumulative DR per aspiration increased from 28.0% in 2011 to 28.9% in 2012. The overall perinatal mortality rate per 1000 births was 21.4 following fresh IVF/ICSI and 15.9 per 1000 following FET.Limitations, Reasons For Caution: The data presented depend on the quality and completeness of data submitted by individual countries to ICMART directly or through regional registries. This report covers approximately two-thirds of` world ART activity, with a major missing country, China. Continued efforts to improve the quality and consistency of reporting ART data by registries are still needed, including the use of internationally agreed standard definitions (International Glossary of Infertility and Fertility Care).Wider Implications Of the Findings: The ICMART world reports provide the most comprehensive global statistical census and review of ART utilization, effectiveness, safety and quality. While ART treatment continues to increase globally, the wide disparities in access to treatment, procedures performed and embryo transfer practices warrant attention by clinicians and policy makers. With the increasing practice of SET and of freeze all and resulting increased proportion of FET cycles, it is clear that PR and DR per aspiration in fresh cycles do not give an overall accurate estimation of ART efficiency. It is time to use cumulative live birth rate per aspiration, combining the outcomes of FET cycles with the associated fresh cycle from which the embryos were obtained, and to obtain global consensus on this approach.Study Funding/competing Interest(s): The authors declare no conflict of interest and no specific support from any organizations in relation to this manuscript. ICMART gratefully acknowledges financial support from the following organizations: American Society for Reproductive Medicine; European Society for Human Reproduction and Embryology; Fertility Society of Australia; Japan Society for Reproductive Medicine; Japan Society of Fertilization and Implantation; Red Latinoamericana de Reproduccion Asistida; Society for Assisted Reproductive Technology; Ferring Pharmaceuticals and Abbott (both providing ICMART unrestricted grants unrelated to world reports).Trial Registration Number: NA. [ABSTRACT FROM AUTHOR]

This commentary outlines the importance of utilizing assisted reproductive technology (ART) as an indicator of access to infertility care and provides a standard way of reporting utilization to facilitate international comparisons. Factors that influence ART utilization as well as underlying inequalities and inequities in access to care are discussed. The relevance of a marker that can inform and evaluate policy initiatives, monitor progress and document change is emphasized. [ABSTRACT FROM AUTHOR]

This study estimates the future utilization of medically assisted fertility treatments in Australia, focusing on assisted reproductive technologies (ARTs), intrauterine insemination (IUI), and ovulation induction. A multistate cohort component population projection model is used to determine future fertility rates from 2016 to 2026 by age and education level. These are combined with information on recent trends in use and success rates to indirectly estimate future age-specific probabilities of fertility treatment utilization. The number of ART cycles is expected to increase by 61 per cent between 2016 and 2026 if treatment success rates remain at 2015 levels, or by 34 per cent if recent improvements in ART success rates continue. The model also predicts that numbers of IUI cycles and ovulation induction cycles will decrease by 17 and 3 per cent, respectively. This research confirms the importance of including both technological improvements and socio-demographic changes when predicting future fertility treatment utilization. [ABSTRACT FROM AUTHOR]

Study Question: How did general practitioners (GPs) (family physicians) manage infertility in females and males in primary care between 2000 and 2016?Summary Answer: The number of GP infertility consultations for females increased 1.6 folds during the study period, with 42.9% of consultations resulting in a referral to a fertility clinic or specialist, compared to a 3-fold increase in the number of consultations for men, with 21.5% of consultations resulting in a referral.What Is Known Already: Infertility affects one in six couples and is expected to increase with the trend to later childbearing and reports of declining sperm counts. Despite GPs often being the first contact for infertile people, very limited information is available on the management of infertility in primary care.Study Design, Size, Duration: Data from the Bettering the Evaluation and Care of Health programme were used, which is a national study of Australian primary care (general practice) clinical activity based on 1000 ever-changing, randomly selected GPs involved in 100 000 GP-patient consultations per year between 2000 and 2016.Participants/materials, Setting, Methods: Females and males aged 18-49 years attending GPs for the management of infertility were included in the study. Details recorded by GPs included patient characteristics, problems managed and management actions (including counselling/education, imaging, pathology, medications and referrals to specialists and fertility clinics). Analyses included trends in the rates of infertility consultations by sex of patient, descriptive and univariate analyses of patient characteristics and management actions and multivariate logistic regression to determine which patient and GP characteristics were independently associated with increased rates of infertility management and referrals.Main Results and the Role Of Chance: The rate of infertility consultations per capita increased 1.6 folds for women (17.7-28.3 per 1000 women aged 18-49 years) and 3 folds for men over the time period (3.4-10.2 per 1000 men aged 18-49 years). Referral to a fertility clinic or relevant specialist occurred in 42.9% of female infertility consultations and 21.5% of male infertility consultations. After controlling for age and other patient characteristics, being aged in their 30s, not having income assistance, attending primary care in later years of the study and coming from a non-English-speaking background, were associated with an increased likelihood of infertility being managed in primary care. In female patients, holding a Commonwealth concession card (indicating low income), living in a remote area and having a female GP all indicated a lower adjusted odds of referral to a fertility clinic or specialist.Limitations, Reasons For Caution: Data are lacking for the period of infertility and infertility diagnosis, which would provide a more complete picture of the epidemiology of treatment-seeking behaviour for infertility. Australia's universal insurance scheme provides residents with access to a GP, and therefore these findings may not be generalizable to other settings.Wider Implications Of the Findings: This study informs public policy on how infertility is managed in primary care in different patient groups. Whether the management actions taken and rates of secondary referral to a fertility clinic or specialist are appropriate warrants further investigation. The development of clinical practice guidelines for the management of infertility would provide a standardized approach to advice, investigations, treatment and referral pathways in primary care.Study Funding/competing Interest(s): This paper is part of a study being funded by an Australian National Health and Medical Research Council project grant APP1104543. G.C. reports that she is an employee of The University of New South Wales (UNSW) and Director of the National Perinatal Epidemiology and Statistics Unit (NPESU), UNSW. The NPESU manages the Australian and New Zealand Assisted Reproductive Technology Database on behalf of the Fertility Society of Australia. W.L. reports being a part-time paid employee and minor shareholder of Virtus Health, a fertility company. R.N. reports being a small unitholder in a fertility company, receiving grants for research from Merck and Ferring and speaker travel grants from Merck.Trial Registration Number: NA. [ABSTRACT FROM AUTHOR]

Study Question: What is the number of oocytes where the maximum cumulative live birth rate per aspiration (CLBR) is observed during ART in women of different ages?Summary Answer: The maximum CLBR was observed when around 25 oocytes were retrieved in women between 18-35 years of age, around 9 oocytes in women more than 45 years of age and continued to increase beyond 30 oocytes in women between 36-44 years of age.What Is Known Already: The live birth rate per fresh or frozen/thaw embryo transfer (FET) procedure has traditionally been the main measure of ART success. However, with the introduction of highly efficient embryo cryopreservation methods, CLBR encompassing live delivery outcomes from the fresh and all subsequent FET following a single ovarian stimulation and oocyte collection is increasingly viewed as a more meaningful measure of treatment success. There is evidence suggesting that larger oocyte yields are associated with increased likelihood of cumulative live birth per aspiration. Whether this association is the same across female ages has not yet been properly investigated.Study Design, Size, Duration: This is a large retrospective population-based cohort study using data from the Australian and New Zealand Assisted Reproduction Database (ANZARD). ANZARD contains information from all ART treatment cycles carried out in all fertility centres in Australia and New Zealand. Overall, 221 221 autologous oocyte aspiration cycles carried out between January 2009 to December 2015 were included in the analysis.Participants/materials, Setting, Methods: Cumulative live birth per aspiration was defined as at least one liveborn baby at ≥20 weeks gestation resulting from an ART aspiration cycle, including all fresh and FET resulting from the associated ovarian stimulation, until one live birth occurred or all embryos were used. Cycles where no oocytes were retrieved were excluded from analysis as there is no possibility of live birth. Analyses of data were performed using generalized estimating equations to account for the clustered nature of data (multiple cycles undertaken by a woman). Univariate and multivariable regression analysis was performed to identify and adjust for factors known to independently affect cumulative live birth per aspiration. An interaction term between female age and the number of oocytes retrieved was included to assess whether the age of the women was associated with a different optimal number of oocytes to achieve at least one live birth from an aspiration cycle (i.e. the effect-modifying role of female age). The likelihood of cumulative live birth per aspiration was calculated as odds ratios (ORs) with 95% CI.Main Results and the Role Of Chance: The median number of oocytes retrieved was 7 (interquartile range, 4-12) and median age of patients was 36 (interquartile range, 33-40). The overall CLBR was 32.2%. The results from the multivariable regression analysis showedthat the number of oocytes retrieved remained a significant predictor (P < 0.001) of cumulative live birth per aspiration after adjusting for female age, parity and cycle count. Compared to the reference group of 10-14 oocytes retrieved, the adjusted odds for cumulative live birth per aspiration increased with the number of oocytes retrieved: 1-3 oocytes, 0.21 (95% CI, 0.20-0.22); 4-9 oocytes, 0.56 (95% CI, 0.55-0.58); 15-19 oocytes, 1.38 (95% CI, 1.34-1.43); 20-24 oocytes, 1.75 (95% CI, 1.67-1.84); and 2.10 (95% CI, 1.96-2.25) with more than 25 oocytes. After stratifying by female age group, the rate of increase in CLBR per additional oocyte retrieved was lower in the older age groups, indicating that higher oocyte yields were more beneficial in younger women. CLBR of patients in the <30 years and 30-34 years age groups appeared to reach a plateau (with only minimal increase in CLBR per additional oocyte retrieved) after retrieval of 25 oocytes at 73% and 72%, respectively, while CLBR of patients in the 35-39 years and 40-44 years age groups continued to increase with higher oocyte yields, reaching 68% and 40%, respectively, when 30 or more oocytes were retrieved. CLBR of patients aged 45 years and above remained consistently below 5%. Findings suggest that the number of oocytes retrieved where CLBR appears to be maximized is around 25 in women between 18-35 years, more than 30 in women between 36-44 years and around 9 in women 45 years and older. However, results for women aged 45 years and older may not be as robust due to the relatively small sample size available in this age group.Limitations, Reasons For Caution: As with all large retrospective database studies, there are potential confounders that cannot be accounted for. Despite the current study being based on complete ascertainment of ART cycles across two countries, ovarian stimulation protocols, oocyte quality parameters and a number of important patient characteristics are not collected by ANZARD. Additionally, a small number of cycles were available for women over 45 years yielding more than 15 oocytes, making these estimates unreliable.Wider Implications Of the Findings: The results from this study demonstrate that the number of oocytes retrieved where the maximum CLBR is observed during ART is dependent on female age. This provides information for clinicians and patients to understand the modifying effect of age on the number of oocytes retrieved and the likelihood of success with ART.Study Funding/competing Interest(s): No external funding was used for this study. The Fertility Society of Australia funds the National Perinatal Epidemiology and Statistics Unit to manage ANZARD and conduct national reporting of ART in Australia and New Zealand. Associate Professor Georgina Chambers (G.C.) is employed by the University of New South Wales (UNSW) and is director of the National Perinatal Epidemiology and Statistics Unit at UNSW. G.C. was also a paid member of the Australian governments Medicare Benefits Scheme taskforce on assisted reproductive technologies in 2017. [ABSTRACT FROM AUTHOR]

Objectives: To estimate cumulative live birth rates (CLBRs) following repeated assisted reproductive technology (ART) ovarian stimulation cycles, including all fresh and frozen/thaw embryo transfers (complete cycles).Design, Setting and Participants: Prospective follow-up of 56 652 women commencing ART in Australian and New Zealand during 2009-2012, and followed until 2014 or the first treatment-dependent live birth.Main Outcome Measures: CLBRs and cycle-specific live birth rates were calculated for up to eight cycles, stratified by the age of the women (< 30, 30-34, 35-39, 40-44, > 44 years). Conservative CLBRs assumed that women discontinuing treatment had no chance of achieving a live birth if had they continued treatment; optimal CLBRs assumed that they would have had the same chance as women who continued treatment.Results: The overall CLBR was 32.7% (95% CI, 32.2-33.1%) in the first cycle, rising by the eighth cycle to 54.3% (95% CI, 53.9-54.7%) (conservative) and 77.2% (95% CI, 76.5-77.9%) (optimal). The CLBR decreased with age and number of complete cycles. For women who commenced ART treatment before 30 years of age, the CLBR for the first complete cycle was 43.7% (95% CI, 42.6-44.7%), rising to 69.2% (95% CI, 68.2-70.1%) (conservative) and 92.8% (95% CI, 91.6-94.0) (optimal) for the seventh cycle. For women aged 40-44 years, the CLBR was 10.7% (95% CI, 10.1-11.3%) for the first complete cycle, rising to 21.0% (95% CI, 20.2-21.8%) (conservative) and 37.9% (95% CI, 35.9-39.9%) (optimal) for the eighth cycle.Conclusion: CLBRs based on complete cycles are meaningful estimates of ART success, reflecting contemporary clinical practice and encouraging safe practice. These estimates can be used when counselling patients and to inform public policy on ART treatment. [ABSTRACT FROM AUTHOR]

Study Question: Have ART live birth rates improved in Australia over the last 12 years?Summary Answer: There were striking improvements in per-cycle live birth rates observed for frozen/thaw embryo transfers, blastocyst transfer and single embryo transfer (SET), while live birth rates following ICSI were lower than IVF for non-male factor infertility in most years.What Is Already Known: ART and associated techniques have become the predominant treatment of infertility over the past 30 years in most developed countries. However, there are differences in ART laboratory and clinical practices, and success rates worldwide. Australia has one of the highest ART utilization rates and lowest multiple birth rates in the world, thus providing a unique setting to investigate the contribution of common ART strategies in an unrestricted population of patients to ART success rates.Study Design, Size, Duration: A retrospective cohort study of 585 065 ART treatment cycles performed in Australia between 2002 and 2013 using the Australian and New Zealand Assisted Reproduction Database (ANZARD).Participants Materials, Setting, Method: An unrestricted population of all women who underwent autologous ART treatment between 2002 and 2013. Visual descriptive analysis was used to assess the trends in ART procedures by the calendar years. Adjusted odds ratios (aORs) of a live birth for four common ART techniques were calculated after controlling for important confounders including female age, infertility diagnosis, stage of the embryo (blastocyst versus cleavage stage), type of embryo (fresh versus thawed), fertilization method (IVF versus ICSI) and number of embryos transferred (SET versus multiple embryos).Main Results and the Role Of Chance: The overall live birth rate per embryo transfer increased from 19.2% in 2002 to 23.3% in 2013 (21.9-24.3% for fresh embryo transfers and 14.6-23.3% for frozen/thaw embryo transfers). This occurred concurrently with an increase in SET from 29.7% to 78.9%, and an increase in the average age of women undergoing treatment from 35.0 to 35.9 years. Individuals who had a frozen/thaw embryo transfer cycle in 2002 had 43% (aOR: 0.57, 95% CI: 0.53-0.61) reduced odds of a live birth compared with a fresh embryo transfer cycle. This contrasted with 16% (aOR: 0.84, 95% CI: 0.80-0.98) reduced odds of a live birth from frozen/thaw embryo transfer cycles in 2013. In 2013, the odds of blastocyst transfer resulting in a live birth were more than twice as great as for cleavage stage transfer (aOR 2.01, 95% CI: 1.92-2.11). The adjusted odds of live birth per SET compared with multiple embryo transfer increased significantly over the last 12 years, from a 38% reduced odds of a live birth follow SET in 2002 (aOR: 062, 95% CI: 0.57-0.67) compared to an 8% reduced odds in 2013 (aOR: 0.92, 95% CI: 0.87-0.98). The aOR of a live birth using ICSI compared to IVF in non-male factor patients was lower in most years bringing into question its widespread use.Limitation, Reasons For Caution: This is a retrospective cohort analysis and cannot confirm causality. High-level evidence on the effectiveness of particular ART techniques, particularly ICSI and blastocyst culture, requires prospective randomized controlled trials or detailed statistical analysis using large-scale data that counts for fertilization failure, embryo loss, prognostic factors and cycle characteristics.Wider Implication Of the Findings: The most striking improvements in ART success rates in Australia have been observed for frozen/thaw embryo transfers, blastocyst transfer and SET. Further studies of the role of ICSI in non-male factor infertility and blastocyst transfer success rates that take into account embryo loss are needed.Study Funding/competing Interests: No funding was received to undertake this study. The authors declare that they do not have competing interests with this study.Trial Registration Number: NA. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether there is an increased risk of preterm birth with blastocyst transfer compared with cleavage-stage embryo transfer (ET) after assisted reproductive technology (ART).Design: A retrospective, population-based study.Setting: Not applicable.Patient(s): A total of 50,788 infants conceived after ART treatment performed from 2009 to 2012.Intervention(s): None.Main Outcome Measure(s): The rates of preterm birth, low birth weight (LBW), and small for gestational age (SGA) for 43,952 singleton and 3,418 twin deliveries after transfers of blastocyst or cleavage-stage embryos.Result(s): Among singletons, there was no significant difference in the odds of preterm birth between blastocyst and cleavage-stage ET (9.1% compared with 9.3%, respectively, adjusted odds ratio 1.00, 95% confidence interval 0.94-1.08). Among twins, the crude rates of preterm birth were similar after blastocyst and cleavage-stage ETs (61.5% and 64.4%, respectively). However, after adjusting for potential confounders, blastocyst transfer was associated with a lower odds of preterm birth among twins (adjusted odds ratio 0.80, 95% confidence interval 0.70-0.93). There was no difference in risks of LBW and SGA between blastocyst and cleavage-stage ETs for both singletons and twins after adjusting for potential confounders.Conclusion(s): In contrast with the findings from a number of other studies, blastocyst culture in Australian and New Zealand is not associated with an increased risk of preterm, LBW, and SGA for singletons. Further studies are needed to assess longer-term outcomes of children born after ART treatment and possible biological or treatment factors related to adverse outcomes. [ABSTRACT FROM AUTHOR]

Objective To study the value of a population view in assessing assisted reproductive technology (ART) multiple-gestation infants. Design Descriptive comparison of ART treatment and population statistics in seven developed countries (United States [U.S.], South Korea, United Kingdom, the Netherlands, Australia, Belgium, Denmark) with varying ART utilization and single-embryo transfer (SET) rates. Setting Not applicable. Patient(s) Not applicable. Intervention(s) None. Main Outcome Measure(s) The contribution of ART multiple-gestation infants to the total number of multiple-gestation infants in a population was calculated in relation to utilization of ART and SET rates. Result(s) The number of ART treatments leading to embryo transfer varied from 304 per million inhabitants in the U.S. to 1,518 in Denmark. The percentage of ART cycles that utilized SET varied from 8.8% in South Korea to 53.3% in Australia. Reflecting both utilization rates and SET rates, the percentage of multiple-gestation infants in the population attributed to ART ranged from 14.7% in South Korea to 29.0% in Denmark. Conclusion(s) In seven countries, the contribution of ART multiple-gestation infants to all multiple-gestation infants varies from 14.7% to 29.0%, a percentage that was influenced by both the SET rate per cycle and ART utilization rates. In the monitoring of safety and efficacy of fertility treatment, registration of the percentage of SET cycles alone might not be sufficient. [ABSTRACT FROM AUTHOR]

Alongside the debate around clinical, scientific, and ethical aspects of assisted reproductive technology (ART), there exists a parallel debate around the economics of ART treatment and what is the most appropriate funding framework for providing safe, equitable, and cost-effective treatment. The cost of ART treatment from a patient perspective exhibits striking differences worldwide due to the costliness of underlying health care systems and the level of public and third-party subsidization. These relative cost differences affect not only who can afford to access ART treatment but how ART is practiced in terms of embryo transfer practices; in turn significantly impacting the health outcomes and costs of caring for ART conceived children. Although empirical evidence indicates that ART treatment is “good value money” from a societal and patient perspective, the challenge remains to communicate this to policy makers, primarily because fertility treatments are not easily accommodated by traditional health economic methods. Furthermore, with global demand for ART treatment likely to increase, it is important that future funding decisions are informed by what has been learned about how costs and economic incentives influence equity of access and clinical practice. In this review we provide an international perspective on the costs and consequences of ART and summarize key economic considerations from the perspective of ART patients, providers, and society as a whole in the coming decade. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Given similar socio-demographic profiles and costs of healthcare, why has Australia been significantly more successful than the UK in reducing the assisted reproductive technology (ART) multiple birth rate? SUMMARY ANSWER The Australian model of supportive public ART funding, permissive clinical guidelines and an absence of published clinic league tables has enabled Australian fertility specialists to act collectively to achieve rapid and widespread adoption of single embryo transfer (SET). WHAT IS KNOWN ALREADY There are striking differences in ART utilization and clinical practice between Australia and the UK. The ART multiple birth rate in Australia is <8% compared with slightly <20% in the UK. The role played by public funding, clinical guidelines, league tables and educational campaigns deserves further evaluation. STUDY DESIGN, SIZE, DURATION Parallel time-series analysis was performed on ART treatment and outcome data sourced from the Human Fertilisation and Embryology Authority (HFEA) ART Registry and the Australian and New Zealand Assisted Reproduction Database (ANZARD). Funding arrangements, clinical practice guidelines and key professional and public education campaigns were mapped to trends in clinical practice and ART treatment outcomes between 2001 and 2010. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 425 360 and 422 003 autologous treatment cycles undertaken between 2001 and 2010 in the UK and Australia were analysed. MAIN RESULTS AND THE ROLE OF CHANCE From 2001 to 2010, the most striking difference in clinical practice was the increase in SET cycles in Australia from 21 to 70% of cycles, compared with an increase from 8.4 to 31% in the UK. In 2004–2005, both countries introduced clinical guidelines encouraging safe embryo practices, however, Australia has a history of supportive funding for ART, while the National Health Service has a more restrictive and fragmented approach. While clinical guidelines and education campaigns have an important role to play, funding remains a key element in the promotion of SET. LIMITATIONS, REASONS FOR CAUTION This is a descriptive population study and therefore quantifying the independent effect of differential levels of public funding was not possible. WIDER IMPLICATIONS OF THE FINDINGS With demand for ART continuing to increase worldwide, it is imperative that we remove barriers that impede safe embryo transfer practices. This analysis highlights the importance of supportive public funding in achieving this goal. STUDY FUNDING/COMPETING INTEREST(S) No specific funding was received to undertake this study. G.M.C. reports receiving grant support to her institution from the Australian Government, Australian Research Council (ARC) Linkage Grant No LP1002165; ARC Linkage Grant Partner Organisations are IVFAustralia, Melbourne IVF and Queensland Fertility Group. The Fertility Society of Australia (FSA) paid her for 1 week of consultancy work in 2009. Y.A.W. does not report any conflict of interest. M.G.C. reports being a shareholder of IVFAustralia. V.P.H. reports being employed by a grant to his institution from the ARC, Linkage Grant No LP1002165; ARC Linkage Grant Partner Organisations are IVFAustralia, Melbourne IVF and Queensland Fertility Group. E.A.S. reports receiving grant support to her institution from the Australian Government, National Health and Medical Research Council (NHMRC), ARC, National Breast Cancer Foundation, International Vasa Praevia Foundation, the FSA and Australian Institute of Health and Welfare. She is Head of Research, Family Planning NSW. H.I.A. reports being Director of Lister Fertility Clinic, the largest private fertility clinic in UK, and is a member of HFEA. W.L. reports receiving grant support to his institution from the ... [ABSTRACT FROM PUBLISHER]

The article discusses a study to mitigate the number of fetuses produced through assisted reproductive technology (ART) in Australia, and the cost savings this would provide the government. It states that data was gleaned between 2002 to 2008 from several national medical databases on ART treatment cycles. It found that in that period, the number of multiple births fell from 18.8% to 8.6%, because of improved methods and technology, saving the government 47.6 million dollars.

BACKGROUND Despite the growing use of assisted reproductive technologies (ART) worldwide, there is only a limited understanding of the economics of ART to inform policy about effective, safe and equitable financing of ART treatment. METHODS A review was undertaken of key studies regarding the costs and consequences of ART treatment, specifically examining the direct and indirect costs of treatment, economic drivers of utilization and clinical practice and broader economic consequences of ART-conceived children. RESULTS The direct costs of ART treatment vary substantially between countries, with the USA standing out as the most expensive. The direct costs generally reflect the costliness of the underlying healthcare system. If unsubsidized, direct costs represent a significant economic burden to patients. The level of affordability of ART treatment is an important driver of utilization, treatment choices, embryo transfer practices and ultimately multiple birth rates. The costs associated with caring for multiple-birth ART infants and their mothers are substantial, reflecting the underlying morbidity associated with such pregnancies. Investment analysis of ART treatment and ART-conceived children indicates that appropriate funding of ART services appears to represent sound fiscal policy. CONCLUSIONS The complex interaction between the cost of ART treatment and how treatments are subsidized in different healthcare settings and for different patient groups has far-reaching consequences for ART utilization, clinical practice and infant outcomes. A greater understanding of the economics of ART is needed to inform policy decisions and to ensure the best possible outcomes from ART treatment. [ABSTRACT FROM PUBLISHER]

Objective: To compare regulatory and economic aspects of assisted reproductive technologies (ART) in developed countries. Design: Comparative policy and economic analysis. Patient(s): Couples undergoing ART treatment in the United States, Canada, United Kingdom, Scandinavia, Japan, and Australia. Outcome Measure(s): Description of regulatory and financing arrangements, cycle costs, cost-effectiveness ratios, total expenditure, utilization, and price elasticity. Result(s): Regulation and financing of ART share few general characteristics in developed countries. The cost of treatment reflects the costliness of the underlying healthcare system rather than the regulatory or funding environment. The cost (in 2006 United States dollars) of a standard IVF cycle ranged from $12,513 in the United States to $3,956 in Japan. The cost per live birth was highest in the United States and United Kingdom ($41,132 and $40,364, respectively) and lowest in Scandinavia and Japan ($24,485 and $24,329, respectively). The cost of an IVF cycle after government subsidization ranged from 50% of annual disposable income in the United States to 6% in Australia. The cost of ART treatment did not exceed 0.25% of total healthcare expenditure in any country. Australia and Scandinavia were the only country/region to reach levels of utilization approximating demand, with North America meeting only 24% of estimated demand. Demand displayed variable price elasticity. Conclusion(s): Assisted reproductive technology is expensive from a patient perspective but not from a societal perspective. Only countries with funding arrangements that minimize out-of-pocket expenses met expected demand. Funding mechanisms should maximize efficiency and equity of access while minimizing the potential harm from multiple births. [Copyright &y& Elsevier]

Objective: To report the utilization, effectiveness, and safety of practices in assisted reproductive technology (ART) globally in 2013 and assess global trends over time.Design: Retrospective, cross-sectional survey on the utilization, effectiveness, and safety of ART procedures performed globally during 2013.Setting: Seventy-five countries and 2,639 ART clinics.Patient(s): Women and men undergoing ART procedures.Intervention(s): All ART.Main Outcome Measure(s): The ART cycles and outcomes on country-by-country, regional, and global levels. Aggregate country data were processed and analyzed based on methods developed by the International Committee for Monitoring Assisted Reproductive Technology (ICMART).Result(s): A total of 1,858,500 ART cycles were conducted for the treatment year 2013 across 2,639 clinics in 75 participating countries with a global participation rate of 73.6%. Reported and estimated data suggest 1,160,474 embryo transfers (ETs) were performed resulting in >344,317 babies. From 2012 to 2013, the number of reported aspiration and frozen ET cycles increased by 3% and 16.4%, respectively. The proportion of women aged >40 years undergoing nondonor ART increased from 25.2% in 2012 to 26.3% in 2013. As a percentage of nondonor aspiration cycles, intracytoplasmic sperm injection (ICSI) was similar to results for 2012. The in vitro fertilization (IVF)/ICSI combined delivery rates per fresh aspiration and frozen ET cycles were 24.2% and 22.8%, respectively. In fresh nondonor cycles, single ET increased from 33.7% in 2012 to 36.5% in 2013, whereas the average number of transferred embryos was 1.81-again with wide country variation. The rate of twin deliveries after fresh nondonor transfers was 17.9%; the triplet rate was 0.7%. In frozen ET cycles performed in 2013, single ET was used in 57.6%, with an average of 1.49 embryos transferred and twin and triplet rates of 10.8% and 0.4%, respectively. The cumulative delivery rate per aspiration was 30.4%, similar to that in 2012. Perinatal mortality rate per 1,000 births was 22.2% after fresh IVF/ICSI and 16.8% after frozen ET. The data presented depended on the quality and completeness of the data submitted by individual countries. This report covers approximately two-thirds of world ART activity. Continued efforts to improve the quality and consistency of reporting ART data by registries are still needed.Conclusion(s): Reported ART cycles, effectiveness, and safety increased between 2012 and 2013 with adoption of a better method for estimating unreported cycles. [ABSTRACT FROM AUTHOR]

Objective: To systematically quantify the impact of consumer cost on assisted reproduction technology (ART) utilization and numbers of embryos transferred. Design: Ordinary least squared (OLS) regression models were constructed to measure the independent impact of ART affordability—measured as consumer cost relative to average disposable income—on ART utilization and embryo transfer practices. Setting: Not applicable. Patient(s): Women undergoing ART treatment. Intervention(s): None. Main Outcome Measure(s): OLS regression coefficient for ART affordability, which estimates the independent effect of consumer cost relative to income on utilization and number of embryos transferred. Result(s): ART affordability was independently and positively associated with ART utilization with a mean OLS coefficient of 0.032. This indicates that, on average, a decrease in the cost of a cycle of 1 percentage point of disposable income predicts a 3.2% increase in utilization. ART affordability was independently and negatively associated with the number of embryos transferred, indicating that a decrease in the cost of a cycle of 10 percentage points of disposable income predicts a 5.1% increase in single-embryo transfer cycles. Conclusion(s): The relative cost that consumers pay for ART treatment predicts the level of access and number of embryos transferred. Policies that affect ART funding should be informed by these findings to ensure equitable access to treatment and clinically responsible embryo transfer practices. [ABSTRACT FROM AUTHOR]

What is the optimal number of oocytes retrieved at which maximum live birth rate is observed after fresh autologous assisted reproductive technology (ART) cycles for women of different ages? Retrospective cohort study of all fresh autologous ART aspiration cycles (n = 256,643) undertaken in Australia and New Zealand between 2009 and 2015. Primary outcome measure was live birth rate (LBR) (delivery of at least one liveborn baby at 20 weeks' gestation or over per fresh aspiration cycle). Cycles were grouped according to female age (<30, 30–34, 35–49, 40–44 and ≥45 years) and ovarian response (one to three, four to nine, 10–14, 15–19, 20–25 and ≥25 oocytes). Secondary outcome was incidence of ovarian hyperstimulation syndrome (OHSS) requiring hospitalization. At different oocyte yields, LBR per fresh aspiration cycle peaked and then declined at, depending on female age: <30 years: six to 11 oocytes (LBR 31–34%); 30–34 years: 11–16 oocytes (LBR 29–30%); 35–39 years: nine to 17 oocytes (LBR 21–24%); and 40–44 years: 15–17 oocytes (LBR 11–12%). The incidence of OHSS increased significantly with the number of oocytes retrieved, from 1.2% with 15 oocytes retrieved to 9.3% with 30 or more oocytes retrieved (P < 0.001). The optimal number of oocytes at which maximum LBR was observed in a fresh aspiration cycle was highly dependent on age. Because of the observational nature of the results, a cause–effect relationship between the number of oocytes retrieved and LBR should not be assumed; evidence from well-designed randomized control trials is required before clinical advice can be suggested. [ABSTRACT FROM AUTHOR]