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

Does ovarian stimulation regimen affect IVF outcome? a two-centre, real-world retrospective study using predominantly cleavage-stage, single embryo transfer

In this study, ovarian stimulation using highly purified human menopausal gonadotrophin (HP-HMG) and recombinant FSH (rFSH) for IVF were compared in two large assisted reproduction technique centres in Sweden. A total of 5902 women underwent 9631 oocyte retrievals leading to 8818 embryo transfers (7720 on day 2): single embryo transfers (74.2%); birth rate per embryo transfer (27.7%); multiple birth rate (5.0%); incidence of severe ovarian hyperstimulation syndrome (0.71%). Compared with ovarian stimulation with rFSH, women who received HP-HMG were older, had higher dosages of gonadotrophins administered, fewer oocytes retrieved and more embryos transferred. After multivariate analysis controlling for age and generalized estimating equation model, no differences were found in delivery outcomes per embryo transfers between HP-HMG and rFSH, independent of gonadotrophin releasing hormone analogue (GnRH) used. Logit curves for live birth rate suggested differences for various subgroups, most prominently for women with high oocyte yield or when high total doses were used. Differences were not significant, perhaps owing to skewed distributions of the FSH compounds versus age and other covariates. These 'real-life patients' had no differences in live birth rate between HP-HMG and rFSH overall or in subgroups of age, embryo score, ovarian sensitivity or use of GnRH analogue regimen.

Tehran Survey of Potential Risk Factors for Multiple Births

Background

The multiple pregnancy incidence is increasing worldwide. This increased incidence is concerning to the health care system. This study aims to determine the frequency of multiple pregnancy and identify factors that affect this frequency in Tehran, Iran.

MATERIALS AND METHODS

This cross-sectional study included 5170 mothers in labor between July 6-21, 2015 from 103 hospitals with Obstetrics and Gynecology Wards. The questionnaire used in this study consisted of five parts: demographic characteristics; information related to pregnancy; information related to the infant; information regarding the multiple pregnancy; and information associated with infertility. We recruited 103 trained midwives to collect data related to the questionnaire from eligible participants through an interview and medical records review. Frequencies and odds ratios (OR) for the association between multiple pregnancy and the selected characteristics (maternal age, economic status, history of multiple pregnancy in first-degree relatives, and reproductive history) were computed by multiple logistic regression. Stata software, version 13 (Stata Corp, College Station, TX, USA) was used for all statistical analyses.

RESULTS

Multiple pregnancy had a prevalence of 1.48% [95% confidence interval (CI): 1.19-1.85]. After controlling for confounding variables, we observed a significant association between frequency of multiple pregnancy and mother's age (OR=1.04, 95% CI: 1.001-1.09, P=0.044), assisted reproductive technique (ART, OR=6.11, 95% CI: 1.7- 21.97, P=0.006), and history of multiple pregnancy in the mother's family (OR=5.49, 95% CI: 3.55-9.93, P=0.001).

CONCLUSION

The frequency of multiple pregnancy approximated results reported in previous studies in Iran. Based on the results, we observed significantly greater frequency of multiple pregnancy in older women, those with a history of ART, and a history of multiple pregnancy in the mother's family compared to the other variables.

Live birth after fresh versus frozen single blastocyst transfer (Frefro-blastocyst): study protocol for a randomized controlled trial

Background

Multiple pregnancies are one of the major safety concerns of in vitro fertilization (IVF) due to the increased risk of maternal and neonatal complications. Single embryo transfer is the most effective way to reduce the risk of multiple pregnancies. Selection of the embryo and optimization of the implantation environment are crucial to retain the success rate when the number of transferred embryos is diminished. Fresh embryo transfer with supra-physiological levels of hormones has been suggested to have an adverse effect on implantation. Elective frozen embryo transfer has been suggested to result in a higher rate of live birth than fresh embryo transfer. However, there is still a lack of evidence from randomized clinical trials comparing the efficacy and safety between frozen and fresh single blastocyst transfers.

Methods/design

We are conducting a randomized controlled trial in women aged 20–35 undergoing their first cycle of IVF with or without intracytoplasmic sperm injection. After ovarian stimulation with a gonadotropin-releasing hormone antagonist protocol, women who obtain four or more embryos on day 3 of the embryo culture are randomized into two parallel groups: a single fresh blastocyst transfer group and a single frozen blastocyst transfer group (all blastocysts vitrified and a deferred frozen blastocyst transfer). The primary outcome is singleton live birth.

Discussion

The results of this study will provide evidence for the efficacy and safety of the strategy of elective frozen single blastocyst transfer in women with a good prognosis.

Trial registration

Chinese Clinical Trial Registry, ChiCTR-IOR-14005405. Registered on 30 Oct 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1993-5) contains supplementary material, which is available to authorized users.

Pregnancy rates for single embryo transfer (SET) of day 5 and day 6 blastocysts after cryopreservation by vitrification and slow freeze

PURPOSE

The purpose of this study was to compare clinical and ongoing pregnancy rates in cycles with single embryo transfer (SET) of blastocysts cryopreserved on day 5 or day 6. Our aim was to determine whether day 6 blastocysts perform adequately to recommend SET.

METHODS

Retrospective cohort study including 468 transfer cycles for 392 women younger than age 38 undergoing SET at a university-affiliated IVF clinic in the USA. A total of 261 day 5 blastocysts and 207 day 6 blastocysts for frozen-thawed SET between 2010 and 2016 were analyzed. Data included cryopreservation by both a slow freeze method and vitrification.

RESULTS

In total, 59.0% of day 5 SET cycles resulted in a clinical pregnancy compared to 54.1% of day 6 blastocysts (p = 0.54). Ongoing pregnancy rates from day 5 frozen-thawed blastocysts (51.7%) were comparable to day 6 (44.9%, p = 0.14). When looking at vitrified blastocysts only, there were no significant differences between day 5 and day 6 blastocysts, with a clinical pregnancy rate of 69.2% for day 5 and 72.5% for day 6 (p = 0.68).

CONCLUSIONS

SETs of day 6 cryopreserved blastocysts resulted in similar clinical and ongoing pregnancy rates compared to day 5, particularly after vitrification.

Cost-effectiveness of single versus double embryo transfer in IVF in relation to female age

OBJECTIVE

To evaluate the cost-effectiveness of single embryo transfer followed by an additional frozen-thawed single embryo transfer, if more embryos are available, as compared to double embryo transfer in relation to female age.

STUDY DESIGN

We used a decision tree model to evaluate the costs from a healthcare provider perspective and the pregnancy rates of two embryo transfer policies: one fresh single embryo transfer followed by an additional frozen-thawed single embryo transfer, if more embryos are available (strategy I), and double embryo transfer (strategy II). The analysis was performed on an intention-to-treat basis. Sensitivity analyses were carried out to evaluate the robustness of our model and to identify which model parameters had the strongest impact on the results.

RESULTS

SET followed by an additional frozen-thawed single embryo transfer if available was dominant, less costly and more effective, over DET in women under 32 years. In women aged 32 or older DET was more effective than SET followed by an additional frozen-thawed single embryo transfer if available but also more costly.

CONCLUSION

SET followed by an additional frozen-thawed single embryo transfer should be the preferred strategy in women under 32 undergoing IVF. The choice for SET followed by an additional frozen-thawed single embryo transfer or DET in women aged 32 or older depends on individual patient preferences and on how much society is willing to pay for an extra child. There is a strong need for a randomized clinical trial comparing the cost and effects of SET followed by an additional frozen-thawed single embryo transfer and DET in the latter category of women.

Soluble CD146, an innovative and non-invasive biomarker of embryo selection for in vitro fertilization

Although progress was made in in vitro fertilization (IVF) techniques, the majority of embryos transferred fail to implant. Morphology embryo scoring is the standard procedure for most of IVF centres for choosing the best embryo, but remains limited since even the embryos classified as "top quality" may not implant. As it has been shown that i) CD146 is involved in embryo implantation and ii) membrane form is shed to generate soluble CD146 (sCD146), we propose that sCD146 in embryo supernatants may constitute a new biomarker of embryo selection. Immunocytochemical staining showed expression of CD146 in early embryo stages and sCD146 was detected by ELISA and Western-blot in embryo supernatants from D2. We retrospectively studied 126 couples who underwent IVF attempt. The embryo culture medium from each transferred embryo (n = 222) was collected for measurement of sCD146 by ELISA. Significantly higher sCD146 concentrations were present in embryo supernatants that did not implant (n = 185) as compared to those that successfully implanted (n = 37) (1310 +/- 1152 pg.mL-1 vs. 845+/- 1173 pg.mL-1, p = 0.024). Sensitivity analysis performed on single embryo transfers (n = 71) confirmed this association (p = 0.0054). The computed ROC curve established that the optimal sCD146 concentration for embryo implantation is under 1164 pg.mL-1 (sensitivity: 76%, specificity: 48%, PPV: 25% and NPV: 92%). Over this sCD146 threshold, the implantation rate was significantly lower (9% with sCD146 levels >1164 pg.ml-1 vs. 22% with sCD146 levels ≤ 1164 pg.mL-1, p = 0.01). Among the embryos preselected by morphologic scoring, sCD146 determination could allow a better selection of the embryo(s), thus improving the success of elective single embryo transfer. This study establishes the proof of concept for the use of sCD146 as a biomarker for IVF by excluding the embryo with the highest sCD146 level. A multicentre prospective study will now be necessary to further establish its use in clinical practice.

Influence of storage time on vitrified human cleavage-stage embryos froze in open system

BACKGROUND

During in vitro fertilization, rapid growth of vitrification and liquid nitrogen storage of embryos have been well characterized. However, the effect of storage time on vitrified cleavage-stage embryos in an open system is poorly understood.

AIMS

To investigate the influence of storage time on the survival and pregnancy outcomes of vitrified human cleavage-stage embryos froze and stored in an open system.

METHODS

A retrospective study of 786 vitrified-warmed cycles of 735 patients was performed from January 2013 to October 2013. The cycles were divided into five groups according to storage time: 1-3 months, 4-6 months, 7-12 months, 13-24 and 25-60 months. The clinical outcomes of cycles with different storage time were analyzed.

RESULTS

There were no significant differences of the survival rate, clinical pregnancy outcomes, birth rate, gestational weeks and singleton birthweights at various storage times.

CONCLUSION

For vitrified embryos froze and stored in an open system, the storage time would not influence the survival rate and pregnancy outcomes by storage time up to 5 years.

Deciding how many embryos to transfer: ongoing challenges and dilemmas

Despite the risks associated with twin and higher-order multiple births, and calls in many countries for single-embryo transfer as the standard of care for good-prognosis patients, providers frequently transfer additional embryos, raising critical questions as to why this is the case and what can be done about it. In-depth interviews of approximately 1 h each were conducted with 27 IVF providers (17 physicians and 10 other healthcare providers) and 10 patients. Professional guidelines often contain flexibility and ambiguities or are unenforced. Thus, both providers and patients frequently wrestle with several dilemmas. Decisions about the number of embryos to transfer emerge as dyadic, dynamic and affected by several factors (e.g. providers' type of institution, and personal and professional experiences and perceptions of the data), leading to differences in whether, how and with what effectiveness clinicians address these issues with patients. Many clinicians feel that the evidence concerning the apparent increased risk associated with a twin birth is not 'compelling', and patients frequently minimize the hazards. These data, the first to explore several critical aspects of how providers and patients view and make decisions about the number of embryos to transfer, thus highlight tensions, uncertainties and challenges that providers and patients confront, and have key implications for future practice, research, policy and education.

Risk of adverse pregnancy and perinatal outcomes after high technology infertility treatment: a comprehensive systematic review

In the literature, there is growing evidence that subfertile patients who conceived after infertility treatments have an increased risk of pregnancy and perinatal complications and this is particularly true for patients who conceived through use of high technology infertility treatments. Moreover, high technology infertility treatments include many concomitant clinical and biological risk factors. This review aims to summarize in a systematic fashion the current evidence regarding the relative effect of the different procedures for high technology infertility treatments on the risk of adverse pregnancy and perinatal outcome. A literature search up to August 2016 was performed in IBSS, SocINDEX, Institute for Scientific Information, PubMed, Web of Science and Google Scholar and an evidence-based hierarchy was used to determine which articles to include and analyze. Data on prepregnancy maternal factors, low technology interventions, specific procedures for male factor, ovarian tissue/ovary and uterus transplantation, and chromosomal abnormalities and malformations of the offspring were excluded. The available evidences were analyzed assessing the level and the quality of evidence according to the Oxford Centre for Evidence-Based Medicine guidelines and the Grading of Recommendations Assessment, Development, and Evaluation system, respectively. Current review highlights that every single procedure of high technology infertility treatments can play a crucial role in increasing the risk of pregnancy and perinatal complications. Due to the suboptimal level and quality of the current evidence, further well-designed studies are needed.

Embryo multinucleation at the two-cell stage is an independent predictor of intracytoplasmic sperm injection outcomes

OBJECTIVE

To determine the prognostic impact of the nuclear status at the two-cell stage on intracytoplasmic sperm injection (ICSI) outcomes.

DESIGN

Retrospective study.

SETTING

Hospital.

PATIENT(S)

Only ICSI cycles with time-lapse monitoring of transferred embryos with known implantation/delivery data from November 2012 to December 2014 were included. A total of 2,449 embryos were assessed for multinucleation rates at the two- and four-cell stage, and 608 transferred embryos were studied for ICSI outcomes.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Implantation rate (IR) and live birth rate (LBR) according to the number of multinucleated blastomeres at the two-cell stage: none (Without-MNB^2cell), one (MNB^1/2cell), and two (MNB^2/2cell); morphokinetics of MNB^2cell embryos.

RESULT(S)

Embryos with MNB^1/2cell led to lower IR (27.7%) and LBR (22.7%) than embryos Without-MNB^2cell (33.4% and 29.8%, respectively). The MNB^2/2cell embryos led to significantly lower IR (18.3%) and LBR (13.4%) than embryos Without-MNB^2cell. This difference remained significant in multivariate analysis for implantation (odds ratio 0.57; 95% confidence interval 0.34-0.94) and birth (odds ratio 0.46; 95% confidence interval 0.26-0.80), independently of the other significant parameters (women's age, time of two-cell formation, and multinucleation at the four-cell stage). Among implanted MNB^2cell, if cleavage into four cells occurred later than 37 hours after insemination, embryos were significantly more likely to lead to birth.

CONCLUSION(S)

The presence of multinucleation at the two-cell stage and more specifically in both blastomeres had a significant negative impact on birth potential. Thus, embryo multinucleation at the two-cell stage should be used as an additional noninvasive criterion for embryo selection.

Standards of Care in infertility in Europe

Evidence-based medicine is the principal approach to medical practice. There are several debatable issues in infertility, which require clarification. Over the past 20 years, reliable methodology has been developed for the management of infertile couples. This includes high quality diagnostic and therapeutic procedures, which are applied in highly specialised infertility centres. The European Board and College of Obstetrics and Gynaecology (EBCOG) has published Standards of Care for Women's Health in Europe, which should be the cornerstone for the clinicians and service providers in the European Union to establish common protocols within their centres. Each infertility treatment should result in the highest possible success rate and all appropriate measures for the patient's safety should be in place. The treatment protocols should minimise risk of complications, such as ovarian hyperstimulation syndrome (OHSS). The current use of GnRH agonists to trigger final follicle maturation has provided the means for avoiding this syndrome. Additionally, multiple pregnancy rates are still high in assisted reproductive technology (ART). These rates should be reduced by the adoption of single embryo transfer during IVF treatment and by the proper monitoring of ovulation induction protocols. EBCOG Standards of Care for infertility and assisted conception treatment derived from the best available evidence should underpin the provision of high quality infertility services in European countries.

Elective single embryo transfer in women less than age 38 years reduces multiple birth rates, but not live birth rates, in United States fertility clinics

OBJECTIVE

To determine the effect of elective single ET (eSET) on live birth and multiple birth rates by a cycle-level and clinic-level analysis.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

Patient ages <35 and 35-37 years old.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinics were divided into groups based on eSET rate for each age group and aggregate rates of live birth per ET and multiple birth per delivery were calculated. A cycle-level analysis comparing eSET and double ET (DET) live birth and multiple birth rates was also performed, stratified based on total number (2, 3, or 4+) of embryos available, embryo stage, and patient age.

RESULT(S)

There was a linear decrease in multiple birth rate with increasing eSET rate and no significant difference in clinic-level live birth rates for each age group. Cycle-level analysis found slightly higher live birth rates with double ET, but this was mainly observed in women aged 35-37 years or with four or more embryos available for transfer, and confirmed the marked reduction in multiple births with eSET.

CONCLUSION(S)

Our study showed a marked and linear reduction in multiple birth rates, and important, little to no effect on clinic-level live birth rates with increasing rates of eSET supporting the growing evidence that eSET is effective in decreasing the high multiple birth rates associated with IVF and suggests that eSET should be used more frequently than is currently practiced.

Time lapse microscopy is useful for elective single-embryo transfer

The aim of our study was to evaluate time lapse microscopy (TLM) as a selection tool for single-embryo transfer (SET) on day 5, blastocyst stage. An observational cohort study was conducted. Patients who had SET were compared to patients who had double embryo transfer (DET). A total of 108 patients were included in analysis, 83 had SET, and 25 underwent DET. Embryos were incubated and evaluated using TLM. The pregnancy rates were similar between the groups (42.2% in SET and 48.0% in DET). However, the multiple pregnancy rate was significantly higher in the DET group compared to the SET group (41.7% versus 2.9%, respectively; p < 0.001). This study concludes that SET with TLM do not decrease pregnancy rates compared to DET. However, transfers of two embryos increase the rate of multiple pregnancies.

Ethnicity is an independent predictor of IVF-ICSI outcome: a study of 5,549 cycles in Spain and India

AIM

To determine the role of ethnicity on IVF/ICSI outcomes between Indian and white Caucasian women.

SETTINGS AND DESIGN

Retrospective cohort study.

MATERIALS AND METHODS

White Caucasian and Indian women undergoing IVF/ICSI treatment cycles. Total 5549 self, non-donor, fresh IVF cycles conducted from January 2014 to March 2015, out of which, 4227 were white Caucasian and 1322 were Indian. Data were collected on baseline characteristics, IVF cycle parameters and outcomes. Ongoing pregnancy rate (OPR) was measured as main outcome.

RESULTS

Indian women differed significantly from white Caucasian women in baseline characteristics like age (30.6 ± 0.2 versus 37.6 ± 0.1 years; p < 0.001), BMI (22.3 ± 0.2 versus 26.6 ± 1.0 kg/m²; p < 0.05), duration of infertility (6.9 ± 3.0 versus 2.5 ± 0.1 years; p < 0.001) and antral follicle count (AFC) (8.9 ± 0.4 versus 7.5 ± 0.2; p < 0.001). Indian women had lower implantation rate (30.1% versus 39.6%: p < 0.001) and OPR (35.1% versus 41.7%: p < 0.001) compared with white Caucasian women. Regression analysis proved independent effect of ethnicity on OPR (OR 0.944; 95% CI 0.928-0.961: p < 0.001) Conclusions: OPR was significantly lower among Indian ethnic group following IVF/ICSI suggest that ethnicity, like age, is a major and an independent predictor of IVF outcome.

Is elective single-embryo transfer a viable treatment policy in in vitro maturation cycles?

OBJECTIVE

To compare the clinical outcome of single-embryo transfer (SET) with double-embryo transfer (DET) in in vitro maturation (IVM) cycles performed in patients with polycystic ovary syndrome (PCOS), and to determine which factors predict those outcomes.

DESIGN

A retrospective analysis.

SETTING

Private assisted reproduction center.

PATIENT(S)

One hundred and fifty-nine women with PCOS.

INTERVENTION(S)

In vitro maturation with elective SET or DET conducted between September 2007 and May 2014.

MAIN OUTCOME MEASURE(S)

Live-birth rates.

RESULT(S)

Single-embryo transfer was performed in 83 patients (52.2%), and DET was performed in 76 patients (47.7%). When compared with the patients who had DET, the patients who had SET were statistically significantly younger (32.4 ± 3.5 vs. 24.1 ± 4.2 years) and had a shorter infertility duration (9.2 ± 4.5 vs. 4.4 ± 2.1 years), fewer previous ART cycles (<2 prior attempts, 39.5% vs. 6%; ≥2 prior attempts, 60.5% vs. 0), fewer collected oocytes (15.1 ± 4.6 vs. 12.6 ± 3.8), fewer metaphase II oocytes (9.0 ± 4.1 vs. 5.7 ± 2.9), fewer fertilized oocytes (8.2 ± 3.7 vs. 3.6 ± 2.3), and a higher implantation rate (27% vs. 47%). The SET and DET groups had similar embryo quality and similar clinical pregnancy (44.6% vs. 44.7%) and live-birth rates (34.9% vs. 34.2%). Twin pregnancy rates were statistically significantly higher in the DET compared with the SET groups (9.2% vs. 2.4%).

CONCLUSION(S)

In vitro maturation is a successful assisted reproduction technique that can be an alternative to conventional in vitro fertilization in women presenting with PCOS-related infertility. Our observations suggest that SET is a feasible option to prevent multiple pregnancies while maintaining the live-birth rate.

Clinical outcomes of single versus double blastocyst transfer in fresh and vitrified-warmed cycles

Objective

Assisted reproductive technology has been associated with an increase in multiple pregnancies. The most effective strategy for reducing multiple pregnancies is single embryo transfer. Beginning in October 2015, the National Supporting Program for Infertility in South Korea has limited the number of embryos that can be transferred per in vitro fertilization (IVF) cycle depending on the patient's age. However, little is known regarding the effect of age and number of transferred embryos on the clinical outcomes of Korean patients. Thus, this study was performed to evaluate the effect of the number of transferred blastocysts on clinical outcomes.

Methods

This study was carried out in the Fertility Center of CHA Gangnam Medical Center from January 2013 to December 2014. The clinical outcomes of 514 women who underwent the transfer of one or two blastocysts on day 5 after IVF and of 721 women who underwent the transfer of one or two vitrified-warmed blastocysts were analyzed retrospectively.

Results

For both fresh and vitrified-warmed cycles, the clinical pregnancy rate and live birth or ongoing pregnancy rate were not significantly different between patients who underwent elective single blastocyst transfer (eSBT) and patients who underwent double blastocyst transfer (DBT), regardless of age. However, the multiple pregnancy rate was significantly lower in the eSBT group than in the DBT group.

Conclusion

The clinical outcomes of eSBT and DBT were equivalent, but eSBT had a lower risk of multiple pregnancy and is, therefore, the best option.

Pregnancy at very advanced maternal age: a UK population-based cohort study

Objectives

To describe the characteristics, management and outcomes of women giving birth at advanced maternal age (≥48 years).

Design

Population‐based cohort study using the UK Obstetric Surveillance System (UKOSS).

Setting

All UK hospitals with obstetrician‐led maternity units.

Population

Women delivering at advanced maternal age (≥48 years) in the UK between July 2013 and June 2014 (n = 233) and 454 comparison women.

Methods

Cohort and comparison group identification through the UKOSS monthly mailing.

Main outcome measures

Pregnancy complications.

Results

Older women were more likely than comparison women to be overweight (33% versus 23%, P = 0.0011) or obese (23% versus 19%, P = 0.0318), nulliparous (53% versus 44%, P = 0.0299), have pre‐existing medical conditions (44% versus 28%, P < 0.0001), a multiple pregnancy (18% versus 2%, P < 0.0001), and conceived following assisted conception (78% versus 4%, P < 0.0001). Older women appeared more likely than comparison women to have pregnancy complications including gestational hypertensive disorders, gestational diabetes, postpartum haemorrhage, caesarean delivery, iatrogenic and spontaneous preterm delivery on univariable analysis and after adjustment for demographic and medical factors. However, adjustment for multiple pregnancy or use of assisted conception attenuated most effects, with significant associations remaining only with gestational diabetes (adjusted odds ratio [aOR] 4.81, 95% CI 1.93–12.00), caesarean delivery (aOR 2.78, 95% CI 1.44–5.37) and admission to an intensive care unit (aOR 33.53, 95% CI 2.73–412.24).

Conclusions

Women giving birth at advanced maternal age have higher risks of a range of pregnancy complications. Many of the increased risks appear to be explained by multiple pregnancy or use of assisted conception.

Tweetable abstract

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

Maternal and perinatal outcomes after fresh versus frozen embryo transfer-what is the risk-benefit ratio?

Fresh ET has been the conventional strategy in IVF, but there is a growing opinion suggesting that its maternal and perinatal outcomes can be enhanced by a policy of elective freezing of embryos, followed by transfer at a later date. Available studies suggest a number of improved maternal and perinatal outcomes after frozen ET, although there is also a suggestion of large for gestational age babies associated with this strategy. The observational nature of the available data limit our confidence in the results of available studies. A genuinely unbiased estimate of the advantages of a policy of elective ET can only be confirmed by a definitive randomized controlled trial with an adequate length of follow-up of the offspring.

Elective single embryo transfer- the power of one

Despite the highest historical live birth success rates for couples undergoing in vitro fertilization (IVF), there has been an epidemic of iatrogenic twin and higher order gestation conceived from this treatment. Continued improvement in cryopreservation techniques have allowed preservation of supernumerary embryos for use in future cycles, and refinements in culture systems and embryo selection have resulted in the transfer of fewer embryos while maintaining favorable pregnancy rates. The voluntary transfer of a single high quality embryo, elective single embryo transfer (eSET), has significantly reduced multiple gestation rates and maximized the rate of singleton pregnancy without compromising overall success rates. Although eSET is the standard of care in several developed countries, utilization in the United States has been slow. States with mandated IVF insurance have seen decreases in preterm birth rates yielding down stream health care savings. Herein, the evolution and future applications of this practice to reduce the risk of iatrogenic twins is reviewed.

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

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

Risks of spontaneously and IVF-conceived singleton and twin pregnancies differ, requiring reassessment of statistical premises favoring elective single embryo transfer (eSET)

A published review of the literature by Dutch investigators in 2004 suggested significant outcome differences between spontaneously - and in vitro fertilization (IVF) - conceived singleton and twin pregnancies. Here we review whether later studies between 2004-2015 confirmed these findings. Though methodologies of here reviewed studies varied, and all were retrospective, they overall confirmed results of the 2004 review, and supported significant outcome variances between spontaneously- and IVF-conceived pregnancies: IVF singletons demonstrate significantly poorer and IVF twins significantly better perinatal outcomes than spontaneously conceived singletons and twins, with differences stable over time, and with overall obstetrical outcomes significantly improved. Exaggerations of severe IVF twin risks are likely in the 50 % range, while exaggerations of milder perinatal risks are approximately in 25 % range. Though elective single embryo transfers (eSET) have been confirmed to reduce pregnancy chances, they are, nevertheless, increasingly utilized. eSET, equally unquestionably, however, reduces twin pregnancies. Because twin pregnancies have been alleged to increase outcome risks in comparison to singleton pregnancies, here reported findings should affect the ongoing discussion whether increased twin risks are factual. With no risk excess, eSET significantly reduces IVF pregnancy chances without compensatory benefits and, therefore, is not advisable in IVF, unless patients do not wish to conceive twins or have medical contraindications to conceiving twins.

[Pregnancy and obstetric outcomes of elective single versus double cleavage-stage embryo transfer]

OBJECTIVE

To compare the pregnancy and obstetric outcomes in elective single versus two cleavage-stage embryo transfer.

METHODS

Fresh cleavage-stage embryo transfer cycles between January, 2014 and October, 2015 were reviewed, including 39 single embryo transfer (eSET) cycles and 200 double embryo transfer (DET) cycles. The clinical pregnancy rates, implantation rates, multiple pregnancy rates, live birth rate, and obstetric outcomes (gestational age, preterm delivery rate and mean birth weight) were compared between the two groups.

RESULTS

The baseline characteristics were comparable between the two groups. The estradiol level on the day of trigger and the oocyte number were significantly higher in eSET group than in DET group (10654.4 pmol/L vs 8284.2 pmol/L and 8.4 vs 7.0, respectively). No significant difference was found in the pregnancy rate (56.4% vs 66.0%) or live birth rate (48.7% vs 51.5%) between the two groups, and their implantation rates differed significantly (56.4% vs 37.8%). No multiple pregnancies occurred in eSET group while the rate of multiple pregnancies was 22.7% in DET group. The gestational age and mean birth weight were significantly higher in eSET group (P<0.05), and the preterm delivery rate after DET was nearly three times of that after eSET, although this difference was not statistically significant.

CONCLUSIONS

Elective single embryo transfer can be performed without compromising the live birth rates. Multiple pregnancy rates can be significantly reduced with eSET, which also results in a higher chance of delivering a term singleton live birth compared with DET.

Cumulative live birth rates after one or more complete cycles of IVF: a population-based study of linked cycle data from 178,898 women

STUDY QUESTION

What is the chance of a live birth following one or more linked complete cycles of IVF (including ICSI)?

SUMMARY ANSWER

The chance of a live birth after three complete cycles of IVF was 42.3% for treatment commencing from 1999 to 2007.

WHAT IS KNOWN ALREADY

IVF success has generally been reported on the basis of live birth rates after a single episode of treatment resulting in the transfer of a fresh embryo. This fails to capture the real chance of having a baby after a number of complete cycles-each involving the replacement of fresh as well as frozen-thawed embryos.

STUDY DESIGN, SIZE AND DURATION

Population-based observational cohort study of 178 898 women between 1992 and 2007.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants included all women who commenced IVF treatment at a licenced clinic in the UK as recorded in the Human Fertilisation and Embryology Authority (HFEA) national database. Exclusion criteria included women whose treatment involved donor insemination, egg donation, surrogacy and the transfer of more than three embryos. Cumulative rates of live birth, term (>37 weeks) singleton live birth, and multiple pregnancy were estimated for two time-periods, 1992-1998 and 1999-2007. Conservative estimates assumed that women who did not return for IVF would not have the outcome of interest while optimal estimates assumed that these women would have similar outcome rates to those who continued IVF.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 71 551 women commenced IVF treatment during 1992-1998 and an additional 107 347 during 1999-2007. After the third complete IVF cycle (defined as three fresh IVF treatments-including replacement of any surplus frozen-thawed embryos), the conservative CLBR in women who commenced IVF during 1992-1998 was 30.8% increasing to 42.3% during 1999-2007. The optimal CLBRs were 44.6 and 57.1%, respectively. After eight complete cycles the optimal CLBR was 82.4% in the latter time period. The conservative rate for multiple pregnancy per pregnant woman fell from 31.9% during the earlier time period to 26.2% during the latter.

LIMITATIONS AND REASON FOR CAUTION

Linkage of all IVF treatments to individual women was conducted. However, it was not possible to identify with certainty in all cases the episode of ovarian stimulation which generated some of the frozen embryos. Cumulative live birth rates could not be calculated for women who started treatment beyond 2007 as follow-up data were incomplete in some of them. Following a change in legislation in 2008, linked data were only made available for research in women who gave formal consent for this purpose. BMI and ethnicity could not be reported: these demographics are not recorded in the HFEA database.

WIDER IMPLICATIONS OF THE FINDINGS

Our results demonstrate, at a national level, the chances of live birth in couples undergoing a number of complete (fresh and frozen) IVF cycles. They reflect improvements in reproductive technology and a more conservative embryo transfer policy. Although most couples in the UK still do not receive three complete IVF cycles; assuming no barriers to continuation of IVF treatment, around 83% of women receiving IVF would achieve a live birth by the eighth complete cycle, similar to the natural live birth rate in a non-contraception practising population. Our results support the call from NICE to develop consistent IVF policies based on three complete cycles.

STUDY FUNDING/COMPETING INTERESTS

This work was funded by a Chief Scientist Office Postdoctoral Training Fellowship in Health Services Research and Health of the Public Research (Ref PDF/12/06). The views expressed here are those of the authors and not necessarily those of the Chief Scientist Office. S.B. reports grants from Chief Scientist Office Scotland during the conduct of the study. His institution has received support from Pharmaceutical companies (for educational seminars), which is not related to the submitted work. D.J.M., A.M. and A.J.L. have no conflicts of interest to declare.

Increased incidence of gestational hypertension and preeclampsia after assisted reproductive technology treatment

OBJECTIVE

To determine the association between assisted reproductive technology (ART) treatment and the rate of combined gestational hypertension (GH), preeclampsia (PE).

DESIGN

Retrospective population study.

SETTING

Not applicable.

PATIENT(S)

A total of 596,520 mothers (3.6% ART mothers) who gave birth between 2007 and 2011.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Comparison of the rate of GH/PE for ART and non-ART mothers, with odds ratio (OR), adjusted odds ratio (AOR), and 95% confidence interval (CI) used to assess the association between ART and GH/PE.

RESULT(S)

The overall rate of GH/PE was 4.3%, with 6.4% for ART mothers and 4.3% for non-ART mothers. The rate of GH/PE was higher for mothers of twins than singletons (12.4% vs. 5.7% for ART mothers; 8.6% vs. 4.2% for non-ART mothers). The ART mothers had a 17% increased odds of GH/PE compared with the non-ART mothers (AOR 1.17; 95% CI, 1.10-1.24). After stratification by plurality, the difference in GH/PE rates between ART and non-ART mothers was not statistically significant, with AOR 1.05 (95% CI, 0.98-1.12) for mothers of singletons and AOR 1.10 (95% CI, 0.94-1.30) for mothers of twins.

CONCLUSION(S)

The changes in AOR after stratification indicated that multiple pregnancies after ART are the single most likely explanation for the increased rate of GH/PE among ART mothers. The lower rate of GH/PE among mothers of singletons compared with mothers of twins suggests that a policy to minimize multiple pregnancies after ART may reduce the excess risk of GH/PE due to ART treatment.

Two consecutive singleton pregnancies versus one twins pregnancy as preferred outcome of in vitro fertilization for mothers and infants: a retrospective case-control study

OBJECTIVE

Many infertile couples request a multiple embryo transfer because they desire more than one child. Based on this consideration, the current study aimed to compare the reproductive and perinatal outcomes of two consecutive singleton pregnancies versus one twin pregnancy in a large cohort of in vitro fertilization (IVF) patients.

RESEARCH DESIGN AND METHODS

Retrospective analysis of data from patients with clinical twin pregnancy after IVF fresh cycles and from patients with two consecutive IVF fresh cycles and clinical singleton pregnancy.

MAIN OUTCOME MEASURES

Miscarriage rate, delivery rate, gestational age at birth, neonatal birth weight, and perinatal complications. A sub-analysis of data according to vanishing twin syndrome (VTS) was also performed.

RESULTS

A total of 18,703 autologous fresh cycles were analyzed. One hundred seven patients had two consecutive singleton clinical pregnancies, whereas one clinical twin pregnancy occurred in 641 women. In patients who had two consecutive singleton clinical pregnancies the rates of overall pregnancies lost (odds ratio [OR] 4.9, 95% confidence interval [CI] 3.4, 6.9) and live births (OR 0.2, 95% CI 0.1, 0.3) were, respectively, higher and lower when compared to patients who had one clinical twin pregnancy. That data did not change after sub-analysis for VTS. The overall risk of perinatal complications was significantly higher in patients who had one twin delivery rather than patients who had two consecutive singleton deliveries (OR 31.8, 95% CI 14.1, 71.5). No difference between groups was detected in terms of intrauterine/neonatal deaths, perinatal mortality and neonatal intensive care unit admission. Data did not change after adjusting for confounders.

CONCLUSIONS

When compared with two consecutive singleton pregnancies, twin pregnancies are characterized by higher success rates but worse perinatal outcomes irrespectively of VTS. Well designed prospective controlled studies are needed to confirm or rebut current retrospective findings.

DEFINING ELIGIBILITY CRITERIA FOR FUNDING POLICIES AROUND IN VITRO FERTILIZATION

Objectives: This review aims to assess the state of the science around the potential impact of certain patient characteristics on the safety and effectiveness of in vitro fertilization (IVF).

Methods: Following Cochrane Collaboration guidelines and the PRISMA statement, a comprehensive systematic review of reviews and recent primary studies examining the impact of paternal age and maternal age, smoking, and body mass index (BMI) on the safety and effectiveness of IVF was performed. Papers, published between January 2007 and June 2014, were independently reviewed and critically appraised by two researchers using published quality assessment tools for reviews and primary studies. Due to heterogeneity across papers (different study designs and patient selection criteria), a qualitative analysis of extracted information was performed.

Results: Seventeen papers (ten systematic reviews and seven primary studies) were included. They comprised evidence from retrospective observational studies in which maternal age, BMI, and smoking status were explored as part of secondary analyses of larger studies. The majority of papers found that the likelihood of achieving a pregnancy was lower among women who were >40 years, had a BMI ≥ 25 and smoked. Advanced maternal age and BMI were also associated with higher rates of preterm birth and low birth weight.

Conclusions: Based on available evidence, it may be appropriate to consider “maternal age” and “morbid obesity” in public funding policies that aim to maximize the effectiveness of IVF. However, given inconsistencies in the effect of smoking across different pregnancy-related outcomes, support for incorporating it into funding conditions appears weak.

Is mandating elective single embryo transfer ethically justifiable in young women?

Compared with natural conception, IVF is an effective form of fertility treatment associated with higher rates of obstetric complications and poorer neonatal outcomes. While some increased risk is intrinsic to the infertile population requiring treatment, the practice of multiple embryo transfer contributes to these complications and outcomes, especially concerning its role in higher order pregnancies. As a result, several jurisdictions (e.g. Sweden, Belgium, Turkey, and Quebec) have legally mandated elective single-embryo transfer (eSET) for young women. We accept that in very high-risk scenarios (e.g. past history of preterm delivery and poor maternal health), double-embryo transfer (DET) should be prohibited due to unacceptably high risks. However, we argue that mandating eSET for all young women can be considered an unacceptable breach of patient autonomy, especially since DET offers certain women financial and social advantages. We also show that mandated eSET is inconsistent with other practices (e.g. ovulation induction and intrauterine insemination-ovulation induction) that can expose women and their offspring to risks associated with multiple pregnancies. While defending the option of DET for certain women, some recommendations are offered regarding IVF practice (e.g. preimplantation genetic screening and better support of IVF and maternity leave) to incentivise patients to choose eSET.

Elective single-embryo transfer improves cumulative pregnancy outcome in young patients but not in women of advanced reproductive age

PURPOSE

The purpose of the present study is to assess the significance of elective single-embryo transfer (eSET) in older women.

METHODS

The outcomes of assisted reproductive technology between 2001 and 2013 at single institution were retrospectively evaluated. Cumulative live birth rates (CLBRs) in one oocyte retrieval cycle were compared between those who underwent eSET and multiple embryo transfer (MET) in fresh cycles.

RESULTS

The outcomes of 429 eSET cycles and 965 MET cycles were compared. CLBRs in eSET were higher than those of MET in women under 37 and were comparable in women aged 37 and over. The analysis of the outcomes separately in three age subgroups showed a significantly higher CLBR in young eSET (aged under 37) than that in young MET and similar CLBR between older (aged 37-40 and over 40) eSET and MET. Multiple birth rates were lower in eSET in all age groups. Multivariate logistic regression analyses showed that, in women aged under 37, number of frozen embryos, presence of good-quality embryos, and eSET were significantly related to cumulative live birth. In women aged between 37 and 40, age and number of frozen embryos were significantly related, while eSET was not.

CONCLUSIONS

eSET in women under 37 resulted in increased CLBR compared with MET. In women aged between 37 and 40, CLBR in eSET group was similar with that in MET group. In both age groups, eSET reduced multiple birth rates. The significance of eSET in older women is limited presently, and further research on the strategy to improve cumulative outcomes is necessary.

Health and disease in children born after assistive reproductive therapies (ART

In vitro fertilisation (IVF) and other assisted reproductive therapies (ART) offer hope to subfertile couples worldwide. At least 5 million ART children have been born to date. Their health is an issue that is increasingly relevant: first, to those children and young adults themselves; second, to couples considering fertility treatment; and third, to the general population as ART has progressed from experimental treatment to routine practice. Many concerns about the potential risks to these children have been voiced with varying degrees of supportive evidence. This article summarises some key long-term data. Current evidence suggests that ART does increase risk of: higher order pregnancy (with its inherent pre- and perinatal risks); prematurity and low birth weight; congenital malformations in particular of the male urogenital system; imprinting disorders. Reassuringly, evidence points away from an increased overall cancer risk or differences in neurodevelopmental outcomes. Many unknowns remain, including future fertility and cardiovascular risks and risk of cerebral palsy.

Risk of ectopic pregnancy lowest with transfer of single frozen blastocyst

STUDY QUESTION

What type of transferred embryo is associated with a lower rate of ectopic pregnancy?

SUMMARY ANSWER

The lowest risk of ectopic pregnancy was associated with the transfer of blastocyst, frozen and single embryo compared with cleavage stage, fresh and multiple embryos.

WHAT IS KNOWN ALREADY

Ectopic pregnancy is a recognized complication following assisted reproductive technology (ART) treatment. It has been estimated that the rate of ectopic pregnancy is doubled in pregnancies following ART treatment compared with spontaneous pregnancies. However, it was not clear whether the excess rate of ectopic pregnancy following ART treatment is related to the underlying demographic factors of women undergoing ART treatment, the number of embryos transferred or the developmental stage of the embryo.

STUDY DESIGN, SIZE, DURATION

A population-based cohort study of pregnancies following autologous treatment cycles between January 2009 and December 2011 were obtained from the Australian and New Zealand Assisted Reproduction Technology Database (ANZARD). The ANZARD collects ART treatment information and clinical outcomes annually from all fertility centres in Australia and New Zealand.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Between 2009 and 2011, a total of 44 102 pregnancies were included in the analysis. The rate of ectopic pregnancy was compared by demographic and ART treatment factors. Generalized linear regression of Poisson distribution was used to estimate the likelihood of ectopic pregnancy. Odds ratios, adjusted odds ratios (AOR) and 95% confidence intervals (CI) were calculated.

MAIN RESULTS AND THE ROLE OF CHANCE

The overall rate of ectopic pregnancy was 1.4% for women following ART treatment in Australia and New Zealand. Pregnancies following single embryo transfers had 1.2% ectopic pregnancies, significantly lower than double embryo transfers (1.8%) (P < 0.01). The highest ectopic pregnancy rate was 1.9% for pregnancies from transfers of fresh cleavage embryo, followed by transfers of frozen cleavage embryo (1.7%), transfers of fresh blastocyst (1.3%), and transfers of frozen blastocyst (0.8%). Compared with fresh blastocyst transfer, the likelihood of ectopic pregnancy was 30% higher for fresh cleavage stage embryo transfers (AOR 1.30, 95% CI 1.07-1.59) and was consistent across subfertility groups. Transfer of frozen blastocyst was associated with a significantly decreased risk of ectopic pregnancy (AOR 0.70, 95% CI 0.54-0.91) compared with transfer of fresh blastocyst.

LIMITATIONS, REASON FOR CAUTION

A limitation of this population-based study is the lack of information available on clinical- specific protocols and processes for embryo transfer (i.e. embryo quality, cryopreservation protocol, transfer techniques, etc.) and the potential impact on outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

The lowest risk of ectopic pregnancy was associated with the transfer of a single frozen blastocyst. This finding adds to the increasing evidence of better perinatal outcomes following frozen embryo transfers. The approach of freezing all embryos in the initiated fresh cycle and transfer of a single frozen blastocyst in the subsequent thaw cycle may improve the overall pregnancy and birth outcomes following ART treatment, in part by reducing the ectopic pregnancy rate.

STUDY FUNDING/COMPETING INTERESTS

There is no funding for this study. Authors declared no competing interest related to this study.

Is it justified to transfer two embryos in oocyte donation? A pilot randomized clinical trial

Multiple pregnancies involve high obstetric and perinatal risks. The aim of this study is to evaluate, in a pilot randomized control study, if the cumulative pregnancy and live birth rates of elective single embryo transfer (eSET) are comparable to the ones obtained with elective double embryo transfer (eDET). A total of 65 patients with at least two good quality embryos was randomized, 34 (52.3%) assigned to the eSET group and 31 (47.7%) to the eDET group. The cumulative pregnancy rates (eSET: 73.5% and eDET: 77.4%. RR: 0.95 95% CI: 0.72-1.25) and live birth rates (eSET: 58.8% and eDET: 61.3%. RR: 0.96 95% CI: 0.64-1.42) were similar in the two groups. The twin pregnancy rate in the fresh transfers of eDET group was 47.7% and 0% in the eSET group. The medical team decided to interrupt the study for reasons related to risks associated with elevated twin pregnancy rate, leaving low numbers of patients within the study as a result. When considering cumulative success rates, eSET and eDET are similar in terms of efficacy. However, eDET involves an increased and unacceptable twin pregnancy rate. The only prevention strategy is single embryo transfer.

Preterm birth trend in Taiwan from 2001 to 2009

AIM

The aim of this study was to analyze the trends and risk factors of preterm birth from all the women who delivered during 2001-2009 in Taiwan.

MATERIAL AND METHODS

We analyzed the preterm birth rates, the proportions of obstetric antecedents and risk factors in the population of pregnant women and neonatal Apgar scores according to the National Medical Birth Register database from 2001 to 2009. Adjusted odds ratios (OR) with 95% confidence intervals for risk factors of preterm birth were assessed using multivariable logistic regression models. The obstetric antecedents of preterm birth for singletons were stratified by spontaneous preterm labor and indicated preterm delivery (labor induction or elective cesarean delivery).

RESULTS

The preterm birth rate was 8.56% with the majority (89.76%) delivered between 32 and 37 weeks of gestation. A 0.07% annual increase (P < 0.001) in preterm delivery was observed. The greatest risk factors were multiple pregnancies (OR > 20), followed by medical complications (OR > 2.8), congenital malformations (OR > 2), teen pregnancies (OR > 1), and advanced maternal age (OR > 1). Specifically, singleton preterm births comprised 57.3% spontaneous labor and 42.7% indicated delivery. There was a 0.5% annual increase (P < 0.001) in indicated delivery. Incidence of neonates with poor Apgar scores (<7) was significantly different between those with and without medical complications (P < 0.001).

CONCLUSIONS

The preterm birth rate increased significantly from 2001 to 2009 and multiple pregnancies were the most important contributing factor. Most of the singleton preterm births resulted from spontaneous labor, but the proportion of indicated deliveries increased.

Double trouble: should double embryo transfer be banned?

What role should legislation or policy play in avoiding the complications of in-vitro fertilization? In this article, we focus on single versus double embryo transfer, and assess three arguments in favour of mandatory single embryo transfer: risks to the mother, risks to resultant children, and costs to society. We highlight significant ethical concerns about each of these. Reproductive autonomy and non-paternalism are strong enough to outweigh the health concerns for the woman. Complications due to non-identity cast doubt on the extent to which children are harmed. Twinning may offer an overall benefit rather than burden to society. Finally, including the future health costs for children (not yet born) in reproductive policy is inconsistent with other decisions. We conclude that mandatory single embryo transfer is not justified and that a number of countries should reconsider their current embryo transfer policy.

Oocyte donation is an independent risk factor for pregnancy complications: the implications for women of advanced age

Maternal age at first pregnancy and age-related infertility are steadily increasing, and the demand for assisted reproductive technologies (ART) to treat age-related infertility is also on the rise. The latest registry findings from Europe and the United States show that the meager results of ART in women above 43 years of age have not improved much over the past 10 years. The latest evidence shows that the demand for oocyte donation (OD) is steadily increasing. Contrary to previous belief-attributing increased perinatal complications in OD recipients to advanced maternal age and multifetal pregnancy-accumulating evidence from the past few years suggests that OD itself is a significant and independent risk factor for pregnancy complications, mostly for pre-eclampsia. The increased rate of chronic maternal disease and medical complications in pregnancy observed in advanced maternal age, coupled with the growing demand for OD, with its independent association with pre-eclampsia, create an urgent need to adopt a clear policy taking these risks into account. We present recent evidence showing that OD is an independent risk factor for pre-eclampsia and suggest recommendations for women approaching OD treatment in advanced age.

Trends in perinatal health after assisted reproduction: a Nordic study from the CoNARTaS group

STUDY QUESTIONS

Has the perinatal outcome of children conceived after assisted reproductive technology (ART) improved over time?

SUMMARY ANSWER

The perinatal outcomes in children born after ART have improved over the last 20 years, mainly due to the reduction of multiple births.

WHAT IS KNOWN AND WHAT THIS PAPER ADDS

A Swedish study has shown a reduction in unwanted outcomes over time in children conceived after ART. Our analyses based on data from more than 92 000 ART children born in four Nordic countries confirm these findings.

STUDY DESIGN

Nordic population-based matched cohort study with ART outcome and health data from Denmark, Finland, Norway and Sweden.

PARTICIPANTS, SETTING AND METHODS

We analysed the perinatal outcome of 62 379 ART singletons and 29 758 ART twins, born from 1988 to 2007 in four Nordic countries. The ART singletons were compared with a control group of 362 215 spontaneously conceived singletons. Twins conceived after ART were compared with all spontaneously conceived twins (n = 122 763) born in the Nordic countries during the study period. The rates of several adverse perinatal outcomes were stratified into the time periods: 1988-1992; 1993-1997; 1998-2002 and 2003-2007 and presented according to multiplicity.

MAIN RESULTS AND ROLE OF CHANCE

For singletons conceived after ART, a remarkable decline in the risk of being born preterm and very preterm was observed. The proportion of ART singletons born with a low and very low birthweight also decreased. Finally, the stillbirth and infant death rates have declined among both ART singletons and twins. Throughout the 20 year period, fewer ART twins were stillborn or died during the first year of life compared with spontaneously conceived twins, presumably due to the lower proportion of monozygotic twins among the ART twins.

LIMITATIONS, REASONS FOR CAUTION

We were not able to adjust for some potential confounders such as BMI, smoking, length or cause of infertility. The Nordic ART populations have changed over time, and in recent years, both less as well as severely reproductive ill couples are being treated. This may have affected the observed trends.

WIDER IMPLICATIONS OF THE FINDINGS

It is assuring that data from four countries confirm an overall improvement over time in the perinatal outcomes of children conceived after ART. Furthermore, data show the beneficial effect of single embryo transfer, not only in regard to lowering the rate of multiples but also concerning the health of singletons.

STUDY FUNDING/COMPETING INTERESTS

The European Society for Human Reproduction and Embryology (ESHRE), the University of Copenhagen and the Danish Agency for Science, Technology and Innovation has supported the project. The CoNARTaS group has received travel and meeting funding from the Nordic Federation of Obstetrics and Gynecology (NFOG). None of the authors has any competing interests to declare.

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

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