The impact of specific fertility treatments on cognitive development in childhood and adolescence: a systematic review

Assisted reproductive technology and neurodevelopment in children at 1 year of age: a longitudinal birth cohort study

BACKGROUND

With remarkable advancements in assisted reproductive technology (ART), the number of ART-conceived children continues to increase. Despite increased research investigating the outcomes of ART children, evidence on neurodevelopment remains controversial.

OBJECTIVE

The aim of this study was to investigate the association between ART use and neurodevelopment in children at 1 year of age and to determine whether the characteristics of parental infertility and specific ART procedures affect neurodevelopment in children.

STUDY DESIGN

The Jiangsu Birth Cohort enrolled couples who received ART treatment and who conceived spontaneously (2014-2020) in Jiangsu Province, China. In this study, we included 3531 pregnancies with 3840 cohort children who completed neurodevelopment assessment at 1 year of age, including 1906 infants conceived by ART (including 621 twins). Poisson regressions were fitted to estimate unadjusted and adjusted risk ratios (RRs) and 95% confidence intervals (CIs) for ART use with neurodevelopmental outcomes (cognition, receptive communication, expressive communication, fine motor, and gross motor) in children.

RESULTS

Among singletons, ART use was associated with a 24% to 34% decrease in the risk for noncompetent development in 3 domains (cognition, adjusted RR, 0.66; 95% CI, 0.53-0.82; receptive communication, 0.76; 0.64-0.91; expressive communication, 0.69; 0.51-0.93) after adjustment for conventional covariates. However, an inverse association was observed in the gross motor domain, with ART singletons having a greater risk of being noncompetent in gross motor development than their non-ART counterparts (adjusted RR, 1.41; 95% CI, 1.11-1.79). Compared with singletons, twins resulting from ART treatment demonstrated compromised neurodevelopment in several domains. Furthermore, we continued to observe that the transfer of 'poor' quality embryos was associated with greater risks for noncompetent development in receptive communication (adjusted RR, 1.50; 95% CI, 1.05-2.14) and gross motor domains (1.55; 1.02-2.36) among ART singletons.

CONCLUSION

These results generally provide reassuring evidence among singletons born after ART in the cognition, communication, and fine motor domains, but drawn attention to their gross motor development. The quality of transferred embryos in ART treatment might be associated with offspring neurodevelopment; however, the potential associations warrant further validation in independent studies, and the clinical significance needs careful interpretation.

Children born to subfertile couples, how are they doing? Evidence from research

More than 10 million children have been born with assisted reproductive technology (ART) as we begin to enter the third generation of individuals conceived by ART. Here we summarise key messages from an enlarging body of literature regarding their health. Earlier research had pointed towards increases in perinatal, neonatal and neurological risks, such as preterm birth, low birth weight, congenital malformations and cerebral palsy. Many of these risks have continued to persist in most recent work but have shown reduction. Newer research proposes long-term cardiometabolic and endocrine concerns. Fortunately, most reports conclude there is little or no risk of increased childhood malignancy or abnormal neurodevelopment. Moving forward, new research may benefit from changes in comparator groups and a better understanding of infertility per se in ART, and the confounding role it probably plays in many of the known risk associations, to reliably scan the horizon for health threats for individuals born after ART.

Long-term health risk of offspring born from assisted reproductive technologies

Since the world's first in vitro fertilization baby was born in 1978, there have been more than 8 million children conceived through assisted reproductive technologies (ART) worldwide, and a significant proportion of them have reached puberty or young adulthood. Many studies have found that ART increases the risk of adverse perinatal outcomes, including preterm birth, low birth weight, small size for gestational age, perinatal mortality, and congenital anomalies. However, data regarding the long-term outcomes of ART offspring are limited. According to the developmental origins of health and disease theory, adverse environments during early life stages may induce adaptive changes and subsequently result in an increased risk of diseases in later life. Increasing evidence also suggests that ART offspring are predisposed to an increased risk of non-communicable diseases, such as malignancies, asthma, obesity, metabolic syndrome, diabetes, cardiovascular diseases, and neurodevelopmental and psychiatric disorders. In this review, we summarize the risks for long-term health in ART offspring, discuss the underlying mechanisms, including underlying parental infertility, epigenetic alterations, non-physiological hormone levels, and placental dysfunction, and propose potential strategies to optimize the management of ART and health care of parents and children to eliminate the associated risks. Further ongoing follow-up and research are warranted to determine the effects of ART on the long-term health of ART offspring in later life.

Medically assisted reproduction and mental health in adolescence: evidence from the UK Millennium Cohort Study

BACKGROUND

The number and proportion of children conceived through medically assisted reproduction (MAR) is steadily increasing yet the evidence on their mental health in adolescence is inconclusive. Two main mechanisms with opposite effects can explain differences in mental health outcomes by conception mode: while more advantaged parental characteristics could positively influence it, higher parental stress could have a negative influence.

METHODS

Linear and logistic estimations on a longitudinal population-based birth cohort study of 9,897 individuals to investigate whether adolescents conceived through MAR are more likely than naturally conceived (NC) children to experience mental health problems at age 17, as reported by adolescents themselves and their parents. We test whether this association is confounded and/or mediated by parental background characteristics collected when the cohort member was around 9 months old (maternal age, maternal education level, ethnicity, income quintile), family structure variables measured in adolescence (number of siblings in the household at age 15, parental household structure at age 14) or maternal distress at age 14.

RESULTS

Children conceived naturally and through MAR self-reported similar mental health outcomes. The only differences between MAR and NC adolescents are in the parental reports, with parents who conceived through MAR reporting their children had 3.82 (95% CI: 1.140 to 11.54) and 2.35 (95% CI: 1.145 to 4.838) higher odds of falling within the high category of SDQ total difficulties and emotional symptoms scales, respectively. The results did not change on adjustment for mediators, such as maternal distress, number of siblings in the household and parental household structure.

CONCLUSIONS

The results reveal a lack of or small differences in MAR adolescents' mental health outcomes compared to children who were conceived naturally. While the results based on the parental reports could suggest that MAR adolescents are at higher risk of suffering from mental health problems, the differences are small and not supported by adolescents' own reports. The difference between MAR and NC adolescent's parental report might reflect differences in parental concern, their relationship or closeness and can help to reconcile the mixed findings of previous studies.

Evolution of intracytoplasmic sperm injection: From initial challenges to wider applications

Background

In vitro fertilization (IVF) has revolutionized infertility treatment. Nevertheless, male infertility requires more effective solutions. In 1992, the first-ever case of human birth via intracytoplasmic sperm injection (ICSI) was reported. ICSI involves microscopically injecting a sperm into an ovum. Successful ICSI has become a reliable therapy for couples facing infertility, a significant milestone. However, it has also introduced various challenges. This study also delves into ethical dilemmas arising from widespread ICSI use.

Methods

This review traces the history of ICSI, presenting pioneering attempts, first successful attempts, and critical reports on account of the initial skepticism toward the technology. The review also focuses on chronological progress until ICSI was recognized as effective and became widely applied.

Main findings

The review reveals that ICSI, although transformative, presents challenges. Successes include addressing male infertility and aiding fertilization. However, concerns arise regarding optimal sperm and embryo selection, genetic mutations, and long-term health implications. Ethical considerations surrounding ICSI's broad applications also surface.

Conclusions

Despite its success and effectiveness, ICSI is still evolving as a therapeutic method. By comprehensively evaluating the historical progress and the current status of ICSI and exploring its future prospects, this study highlights the importance of ICSI in infertility treatment.

The association between type of conception through medically assisted reproduction and childhood cognition: a Danish population-wide cohort study

BACKGROUND

Previous research has indicated that children conceived through medically assisted reproduction (MAR) generally have cognitive outcomes comparable to or better than naturally conceived children. However, previous studies have been limited in their ability to examine this relationship at a population level and consider variations across different types of MAR.

METHODS

This study utilizes data from all live births in Denmark between 2006 and 2009 (n = 259 608), including a subset of births resulting from MAR conceptions (n = 13 566). The dependent variable is the standardized test scores obtained in the second and third grades of primary schools. A comparison is made between the test scores of children spontaneously conceived (SC) and those conceived through intrauterine insemination (IUI) and assisted reproductive technologies (ART). Ordinary least squares regressions are employed, with a baseline model adjusted only for birth year, as well as models that additionally account for conception-related confounders and sociodemographic family characteristics.

RESULTS

In the baseline analysis, ART- and IUI-conceived children displayed better test scores compared with their SC peers. However, after adjusting for relevant factors, ART-conceived children performed worse than SC peers, while IUI-conceived children performed equally well as SC peers and better than ART-conceived children.

CONCLUSIONS

These results likely reflect differences in the selection process of potential parents into the type of MAR, as well as the consequences of variations in fecundability. Nevertheless, the differences observed across conception types were overshadowed by test score disparities in socioeconomic background.

Long-term outcomes for children conceived by assisted reproductive technology

Worldwide, more than 10 million children have been born after assisted reproduction technology (ART), comprising up to 7.9% of children born in Europe and up to 5.1 % of children born in the US in 2018. The short-term outcome for children born after ART is well-known from numerous publications, with higher rates of preterm birth and low birth weight in children born after fresh embryo transfer and higher rates of large for gestational age and high birth weight in children born after frozen embryo transfer compared with children born after spontaneous conception. Higher rates of birth defects in children born after ART have also been shown consistently over time. Studies on long-term health outcomes after ART are scarcer but suggest an increased risk of altered blood pressure and cardiovascular function in children born after ART. In this review, we summarize long-term health outcomes in children born after ART and discuss whether the increased health risks are associated with intrinsic maternal or paternal factors related to subfertility or ART treatments per se. Finally, we speculate where the future will bring us regarding ART treatment strategies and the safety of the mother and child.

Long-Term Effects of ART on the Health of the Offspring

Assisted reproductive technologies (ART) significantly increase the chance of successful pregnancy and live birth in infertile couples. The different procedures for ART, including in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), intrauterine insemination (IUI), and gamete intrafallopian tube transfer (GIFT), are widely used to overcome infertility-related problems. In spite of its inarguable usefulness, concerns about the health consequences of ART-conceived babies have been raised. There are reports about the association of ART with birth defects and health complications, e.g., malignancies, high blood pressure, generalized vascular functional disorders, asthma and metabolic disorders in later life. It has been suggested that hormonal treatment of the mother, and the artificial environment during the manipulation of gametes and embryos may cause genomic and epigenetic alterations and subsequent complications in the health status of ART-conceived babies. In the current study, we aimed to review the possible long-term consequences of different ART procedures on the subsequent health status of ART-conceived offspring, considering the confounding factors that might account for/contribute to the long-term consequences.

Offspring physiology following the use of IVM, IVF and ICSI: a systematic review and meta-analysis of animal studies

BACKGROUND

Since the birth of the first baby using IVF technology in 1978, over 10 million children have been conceived via ART. Although most aspects of ARTs were developed in animal models, the introduction of these technologies into clinical practice was performed without comprehensive assessment of their long-term safety. The monitoring of these technologies over time has revealed differences in the physiology of babies produced using ARTs, yet due to the pathology of those presenting for treatment, it is challenging to separate the cause of infertility from the effect of treatments offered. The use of systematic review and meta-analysis to investigate the impacts of the predominant ART interventions used clinically in human populations on animals produced in healthy fertile populations offers an alternative approach to understanding the long-term safety of reproductive technologies.

OBJECTIVE AND RATIONALE

This systematic review and meta-analysis aimed to examine the evidence available from animal studies on physiological outcomes in the offspring conceived after IVF, IVM or ICSI, compared to in vivo fertilization, and to provide an overview on the landscape of research in this area.

SEARCH METHODS

PubMed, Embase and Commonwealth Agricultural Bureaux (CAB) Abstracts were searched for relevant studies published until 27 August 2021. Search terms relating to assisted reproductive technology, postnatal outcomes and mammalian animal models were used. Studies that compared postnatal outcomes between in vitro-conceived (IVF, ICSI or IVM) and in vivo-conceived mammalian animal models were included. In vivo conception included mating, artificial insemination, or either of these followed by embryo transfer to a recipient animal with or without in vitro culture. Outcomes included birth weight, gestation length, cardiovascular, metabolic and behavioural characteristics and lifespan.

OUTCOMES

A total of 61 studies in five different species (bovine, equine, murine, ovine and non-human primate) met the inclusion criteria. The bovine model was the most frequently used in IVM studies (32/40), while the murine model was mostly used in IVF (17/20) and ICSI (6/8) investigations. Despite considerable heterogeneity, these studies suggest that the use of IVF or maturation results in offspring with higher birthweights and a longer length of gestation, with most of this evidence coming from studies in cattle. These techniques may also impair glucose and lipid metabolism in male mice. The findings on cardiovascular outcomes and behaviour outcomes were inconsistent across studies.

WIDER IMPLICATIONS

Conception via in vitro or in vivo means appears to have an influence on measurable outcomes of offspring physiology, manifesting differently across the species studied. Importantly, it can be noted that these measurable differences are noticeable in healthy, fertile animal populations. Thus, common ART interventions may have long-term consequences for those conceived through these techniques, regardless of the pathology underpinning diagnosed infertility. However, due to heterogeneous methods, results and measured outcomes, highlighted in this review, it is difficult to draw firm conclusions. Optimizing animal and human studies that investigate the safety of new reproductive technologies will provide insight into safeguarding the introduction of novel interventions into the clinical setting. Cautiously prescribing the use of ARTs clinically may also be considered to reduce the chance of promoting adverse outcomes in children conceived before long-term safety is confidently documented.

The bibliometric analysis of studies on intracytoplasmic sperm injection from 2002 to 2021

BACKGROUND

Infertility is estimated to occur in 1 out of every 4-7 couples. Intracytoplasmic sperm injection (ICSI), a type of assisted reproduction introduced in 1992, has been used across the world for almost all indications of infertility, yielding high pregnancy rates. There is a growing concern worldwide about ICSI since semen quality has declined in recent years, accompanied with the potential risks of this technology. This study aims to analyze the current status and hotspots of ICSI via a bibliometric analysis.

METHODS

We retrieved publications on ICSI from the Web of Science Core Collection database from 2002 to 2021. CiteSpace was used to summarize knowledge mapping of subject categories, keywords, and co-citation relationships with the strongest citation bursts. VOSviewer was used to explore co-citation and co-occurrence relationships for countries, organizations, references, authors, and keywords.

RESULTS

A total of 8271 publications were analyzed between 2002 and 2021. The major findings are as follows: the USA, China, Italy, Japan, and Belgium are the top five prolific countries. The Free University of Brussels, University of Copenhagen, University of Valencia, Ghent University, and the University of California San Francisco are the top five contributing organizations. Fertility and Sterility and Human Reproduction are the most productive and cited journals. The hotspot topics are risks of ICSI, oocyte preservation, live birth rate, infertile men, and embryo quality in the past two decades.

CONCLUSION

This study presents a research overview of ICSI from different perspectives. These findings will contribute to a better understanding of the current status of ICSI research and provide hotspots and trends for future studies.

Adolescent Development and the Parent-Adolescent Relationship in Diverse Family Forms Created by Assisted Reproduction

Assisted reproduction techniques (ARTs) are employed by single individuals and couples who are not otherwise able to conceive spontaneously. While the use of ARTs is increasing, research is lacking on the attempts made by adolescent offspring conceived via ARTs to integrate their ART conception into their identity and negotiate a connection with, and autonomy from, their parents. The present article reviews studies investigating adolescent development and the parent-adolescent relationship in diverse family forms created by ARTs (mainly heterosexual and lesbian parent families), and discusses the results in light of attachment, identity development, and emotional distance regulation theories. Overall, the results indicate that the psychological adjustment of adolescents conceived via ARTs is not undermined by the manner of their conception, and that they enjoy positive relationships with their parents with no difference from those enjoyed by spontaneously conceived adolescents. However, it remains unknown whether the development of a reproductive identity in adolescence is likely to influence adolescents' interest in searching for or contacting their donors, surrogates, and/or donor siblings. The results suggest the relevance of considering the parent-adolescent relationship, disclosure, and identity formation issues when planning psychological counseling and support interventions with ART parents and their adolescent offspring, and emphasize the need to further investigate these aspects in diverse ART families, including single-, gay-, bisexual-, and trans*-parent families.

The Well-Being of Adolescents Conceived Through Medically Assisted Reproduction: A Population-Level and Within-Family Analysis

Medically assisted reproduction (MAR) plays an increasingly important role in the realization of fertility intentions in advanced societies, yet the evidence regarding MAR-conceived children's longer-term well-being remains inconclusive. Using register data on all Finnish children born in 1995-2000, we compared a range of social and mental health outcomes among MAR- and naturally conceived adolescents in population-averaged estimates, and within families who have conceived both through MAR and naturally. In baseline models, MAR-conceived adolescents had better school performance and the likelihood of school dropout, not being in education or employment, and early home-leaving were lower than among naturally conceived adolescents. No major differences were found in mental health and high-risk health behaviours. Adjustment for family sociodemographic characteristics attenuated MAR adolescents' advantage in social outcomes, while increasing the risk of mental disorders. The higher probability of mental disorders persisted when comparing MAR adolescents to their naturally conceived siblings. On average, MAR adolescents had similar or better outcomes than naturally conceived adolescents, largely due to their more advantaged family backgrounds, which underscores the importance of integrating a sociodemographic perspective in studies of MAR and its consequences.

Fetal neurosonography and infant neurobehavior following conception by assisted reproductive technology with fresh or frozen embryo transfer

OBJECTIVE

We aimed to explore fetal cortical brain development by neurosonography in fetuses conceived by assisted reproductive technology (ART), including frozen and fresh embryo transfer (ET), compared with those conceived spontaneously (SC), and to investigate its association with infant neurobehavior at 12 months of age.

METHODS

This was a prospective cohort study of 210 singleton pregnancies, including 70 SC pregnancies, 70 conceived by in-vitro fertilization (IVF) following frozen ET and 70 conceived by IVF after fresh ET. Fetal neurosonography was performed at 32 ± 2 gestational weeks to assess cortical development. Sulci depths were measured offline and normalized by biparietal diameter (BPD). Ages and Stages Questionnaires (ASQ) were completed postnatally, at 12 ± 1 months of corrected age. Neurosonographic findings were adjusted by regression analysis for maternal age, ethnicity, parity, fetal sex and fetal-weight centile and gestational age at scan, and ASQ scores were adjusted for maternal age, ethnicity, parity, educational level and employment status, gestational age at birth, breastfeeding, infant sex and infant age at the ASQ evaluation.

RESULTS

Overall, in comparison to the SC fetuses, fetuses conceived by ART showed statistically significant differences in cortical development, with reduced parieto-occipital sulci depth adjusted for BPD (mean ± SD: fresh ET, 12.5 ± 2.5 vs frozen ET, 13.4 ± 2.6 vs SC, 13.4 ± 2.6, P < 0.001), cingulate sulci depth adjusted for BPD (median (interquartile range (IQR)): fresh ET, 5.8 (4.2-7.4) vs frozen ET, 5.8 (4.1-7.5) vs SC, 6.5 (4.8-7.8), P = 0.001) and calcarine sulci depth adjusted for BPD (median (IQR): fresh ET, 13.5 (10.1-16.1) vs frozen ET, 14.5 (12.1-15.8) vs SC, 16.4 (14.3-17.9), P < 0.001), together with lower Sylvian fissure grading score. Changes in cortical development were more pronounced in the fresh ET than in the frozen ET group. ART infants showed lower ASQ scores as compared to SC infants, particularly in the fresh ET group (mean ± SD global ASQ Z-score: fresh ET, -0.3 ± 0.4 vs frozen ET, -0.2 ± 0.4 vs SC, 0 ± 0.4, P < 0.001).

CONCLUSIONS

Fetuses conceived by ART show a distinctive pattern of cortical development and suboptimal infant neurodevelopment, with more pronounced changes in those conceived following fresh ET. These findings support the existence of in-utero brain reorganization associated with ART and warrant follow-up studies to assess its long-term persistence. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Impact of assisted reproduction techniques on the neuro-psycho-motor outcome of newborns: a critical appraisal

Subfertility and infertility are common problems among couples of reproductive age, and they increasingly require the use of assisted reproductive techniques (ART). Understandably, doubts about the safety of such methods are increasing among future parents. The purpose of this review is to analyse the real impact of ART, such as in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI), on the health of the unborn baby; in particular, this work is focussed on the problems related to the neuro-psycho-motor area. Twenty-four studies were reviewed and outcomes investigated were: risk of the onset of neurodevelopmental diseases, worsening of school cognitive performance and risk of developing infantile cerebral palsy (CP) or neurological sequelae. For the first two outcomes, we did not find a correlation with ART; nevertheless, the results of the included studies about risk of CP are discordant and influenced by various confounding factors, such as pre-term birth and multiple pregnancies.IMPACT STATEMENTWhat is already known on this subject? Assisted reproductive techniques (ART) are the main answer for achieving pregnancy in infertile couples. However, a wide number of studies have tried to focus on possible different outcomes in terms of maternal and foetal/new-born health. Regarding this scenario, a peculiar importance is given to diseases affecting the neuro-psycho-motor area of the new-born. Since this group of detrimental pathologies could heavily affect the new-born's quality of life and require costly social facilities, different studies have tried to focus on possible outcomes after ART.What do the results of this study add? This manuscript provides a review of the literature regarding ART procedures and neuro-psycho-motor implication. A review is strongly required due to the importance of collecting evidence from studies with different methodologies.What are the implications of these findings for clinical practice and/or further research? This manuscript provides evidence about the need for wider and more congruent studies regarding neurodevelopment disorders in new-borns after ART procedures. Data are prone to suggest a slight correlation, but several confounding factors can heavily hamper the possibility to draw a firm conclusion about the topic.

Association between Cognitive Frailty and Adverse Outcomes among Older Adults: A Meta-Analysis

OBJECTIVES

This systematic review and meta-analysis aimed to pool the effect size of the association between cognitive frailty and adverse outcomes (e.g., falls, disability, and hospitalization) among older adults.

DESIGN

Systematic review and meta-analysis.

METHODS

PubMed, ScienceDirect, and Embase were searched from their respective inceptions to June 1, 2022. We extracted prospective cohort studies that reported the association between cognitive frailty and adverse outcomes. Random or fixed-effects models based on heterogeneity were used to pool the effect sizes of independent associations of cognitive frailty, frailty only, and cognitive impairment only with each adverse outcome.

RESULTS

Fifteen studies involving 49,122 older adults were included in the meta-analysis. Older adults with cognitive frailty had higher odds ratios (OR) for falls (1.82, 95% confidence interval [CI]: 1.29-2.58), disability (3.17, 95%CI: 2.24-4.48), and hospitalization (1.78, 95%CI: 1.48-2.14) compared with those without frailty and cognitive impairment. Older adults with frailty only demonstrated a high risk for falls (pooled OR 1.76, 95%CI: 1.25-2.48), disability (pooled OR 1.82, 95%CI: 1.43-2.33), and hospitalization (pooled OR 1.64, 95% CI: 1.45-1.85). The influence of cognitive impairment only on adverse outcomes was lower compared with cognitive frailty or frailty. Subgroup analyses showed that those with cognitive frailty (defined by the frailty phenotype plus Mini-Mental State Examination) were at greater risk for developing adverse outcomes.

CONCLUSION

Our findings indicate that cognitive frailty is an independent risk factor for adverse outcomes (e.g., falls, disability, and hospitalization). Early screening and comprehensive intervention may improve cognitive frailty and reduce the risk for adverse outcomes among older adults.

The Association between Assisted Reproductive Technology and the Risk of Autism Spectrum Disorders among Offspring: A Meta-analysis

BACKGROUND

This review aimed to determine the association between assisted reproductive technology (ART) and increased chances of having an autistic child.

METHODS

The Web of Science, PubMed, and Scopus databases were systematically searched for studies published until December 2020 with the restricted English language. The Newcastle-Ottawa Scale (NOS) for cohort and case-control studies has been used for the evaluation of quality in individual studies. We evaluated the heterogeneity among the studies using I-squared. Publication bias was assessed using the funnel plot and Egger's and Begg's tests. We presented results using odds ratio (OR) and relative ratio (RR) estimates with its 95% confidence intervals (CI) using a randomeffects model.

RESULTS

In total, 18 articles were included in the present study. The overall findings of the present meta-analysis show that the use of ART didn't associate with the risk of autism spectrum disorders (ASD) among offspring based on OR and RR (OR = 1.04, 95% CI: 0.88-1.21) and (RR = 1 .26, 95% CI: 0.96- 1 .55), respectively. We showed a significant association between ART and the risk of ASD in Asia than in the other regions without heterogeneity.

CONCLUSION

Our result showed that the risk of ASD was not increased in children born from ART. Possible interaction between ART and other regions with increased risk of ASD is important to point and future studies of this topic were recommended.

The cognitive development from childhood to adolescence of low birthweight children born after medically assisted reproduction-a UK longitudinal cohort study

Background

Previous research has documented that children conceived through medically assisted reproduction (MAR) are at increased risk of poor birth outcomes, such as low birthweight (LBW), which are risk factors for stunted longer-term cognitive development. However, parents who undergo MAR to conceive have, on average, advantaged socioeconomic backgrounds which could compensate for the negative effects of being born LBW. Previous studies have not analysed whether the negative effects of LBW are attenuated among MAR conceived children.

Methods

We draw on the UK Millennium Cohort Study (sweeps 1–6) which contains a sub-sample of (N = 396) MAR-conceived children. The dependent variable measures cognitive ability at around ages 3, 5, 7, 11 and 14. We examine the cognitive development of four groups of children: MAR-conceived low birthweight (MAR LBW); MAR-conceived non-low birthweight (MAR NLBW); naturally conceived low birthweight (NC LBW); naturally conceived non-low birthweight (NC NLBW). We estimate the two following linear regression models for each sweep: (i) a baseline model to examine the unadjusted association between cognitive development and low birthweight by mode of conception; and (ii) a model adjusted by socio-demographic family characteristics.

Results

In baseline models, MAR LBW children [age 3: β  =  0.021, 95% confidence interval (CI): -0.198, 0.241; age 5: β  =  0.21, 95% CI: 0.009, 0.418; age 7: β  =  0.163, 95% CI: -0.148, 0.474; age 11: β  =  0.003, 95% CI: -0.318, 0.325; age 14: β  =  0.156, 95% CI: -0.205, 0.517], on average perform similarly in cognitive ability relative to NC NLBW at all ages, and display higher cognitive scores than NC LBW children until age 7. When we account for family characteristics, differences are largely attenuated and become close to zero at age 14.

Conclusions

Despite the higher incidence of LBW among MAR compared with NC children, they do not seem to experience any disadvantage in their cognitive development compared with naturally conceived children. This finding is likely explained by the fact that, on average, MAR children are born to socioeconomically advantaged parents.

Whole-Genome Methylation Analysis Revealed ART-Specific DNA Methylation Pattern of Neuro- and Immune-System Pathways in Chinese Human Neonates

The DNA methylation of human offspring can change due to the use of assisted reproductive technology (ART). In order to find the differentially methylated regions (DMRs) in ART newborns, cord blood maternal cell contamination and parent DNA methylation background, which will add noise to the real difference, must be removed. We analyzed newborns’ heel blood from six families to identify the DMRs between ART and natural pregnancy newborns, and the genetic model of methylation was explored, meanwhile we analyzed 32 samples of umbilical cord blood of infants born with ART and those of normal pregnancy to confirm which differences are consistent with cord blood data. The DNA methylation level was lower in ART-assisted offspring at the whole genome-wide level. Differentially methylated sites, DMRs, and cord blood differentially expressed genes were enriched in the important pathways of the immune system and nervous system, the genetic patterns of DNA methylation could be changed in the ART group. A total of three imprinted genes and 28 housekeeping genes which were involved in the nervous and immune systems were significant different between the two groups, six of them were detected both in heel blood and cord blood. We concluded that there is an ART-specific DNA methylation pattern involved in neuro- and immune-system pathways of human ART neonates, providing an epigenetic basis for the potential long-term health risks in ART-conceived neonates.

Association between intracytoplasmic sperm injection and neurodevelopmental outcomes among offspring

PURPOSE

To compare the risk of neurodevelopmental disorders in children conceived via intracytoplasmic sperm injection (ICSI) and those conceived naturally.

MATERIALS AND METHODS

A population-based cohort study using data retrieved from the Taipei Medical University Research Database (TMURD) from January, 2004 to August, 2016. The data included maternal pregnancy history, perinatal history and developmental follow up of their babies up to 5 years of age. The study included 23885 children, of whom 23148 were naturally conceived and 737 were conceived via ICSI. Neurodevelopmental disorders defined by 21 ICD-9-CM codes.

RESULTS

Of the 23885 children enrolled for analysis, 2778 children were included for further subgrouping analysis after propensity matching to reduce bias from maternal factors. The single-birth group included 1752 naturally conceived (NC) children and 438 ICSI children. The multiple-birth group included 294 NC and 294 ICSI children. The risk of neurodevelopmental disorders was not increased for ICSI children in both groups (single birth: adjusted hazard ratio aHR = 0.70, 95% CI = 0.39-1.27, p = 0.243; multiple-birth group aHR = 0.77, 95% CI = 0.43-1.35, p = 0.853). In the single-birth group, multivariate analyses showed that male sex (aHR = 1.81, 95% CI = 1.29-2.54, p < 0.001), and intensive care unit (ICU) admission (aHR = 3.10, 95% CI = 1.64-5.86, p < 0.001) were risk factors for neurodevelopmental disorders. In the multiple-birth group, multivariate analyses demonstrated that ICU admission (aHR = 3.58, 95% CI = 1.82-7.04, p < 0.001), was risk factor for neurodevelopmental disorders.

CONCLUSION

Our study indicated that the use of ICSI does not associated with higher risk of neurodevelopmental disorders in the offspring. But male sex, and ICU admission do have increased risk of neurodevelopmental disorders. However, long term follow up of this cohort on health outcomes in adolescence and adulthood will strengthen the conclusions that ICSI is safe regarding offspring long term outcome.

Obstetrical and Neonatal Outcomes of 3,028 Singletons Born After Advanced ART Techniques: Ejaculated Sperm Intracytoplasmic Sperm Injection, Artificial Oocyte Activation, in Vitro Maturation and Testicular Sperm Extraction

Background: To evaluate obstetrical and neonatal outcomes of singletons conceived after advanced assisted reproductive technology (ART) techniques: conventional IVF pregnancies (C-IVF), ejaculated sperm intracytoplasmic sperm injection (ICSI), assisted oocyte activation (AOA), in vitro maturation (IVM), and testicular sperm extraction (TESE).

Methods: The subjects were 3,028 singletons who were born after fresh or frozen embryo transfer. The subjects were separated into five groups: C-IVF (n = 855), ICSI (n = 1,869), AOA (n = 42), IVM (n = 32), and TESE (n = 230). We evaluated obstetrical and neonatal outcomes calculating the adjusted odds ratio (AOR) using multivariable logistic regression analyses for fresh and frozen embryos and for cleavage and blastocyst transfer. The C-IVF group was used as a background control for the ICSI group. Moreover, the TESE, AOA, and IVM groups were compared to the ICSI group to evaluate the effects of the ICSI procedure itself.

Results: The incidence of perinatal complications was significantly lower in the ICSI-fresh group (AOR = 0.29, 95% CI: 0.10–0.83, p ¡ 0.05). Regarding sex ratio, the IVM was significantly associated with sex ratio imbalance toward female in both fresh and frozen groups (AOR = 0.30, 95% CI: 0.10–0.96, AOR = 0.27, 95% CI: 0.07–0.98, p ¡ 0.05). On the other hand, there were no significant differences in preterm birth rate, low birth weight rate and congenital abnormalities rate between conventional IVF, ICSI, and the other groups.

Conclusions: There were no negative effects on obstetrical and neonatal outcomes between conventional IVF and ICSI. Although this was a limited sample size study, advanced ART technologies such as AOA, IVM, and TESE also seem to have a low risk of adverse impact on obstetrical and neonatal outcomes but may have a slight impact on sex ratio.

School performance in children born after ICSI

STUDY QUESTION

Do children conceived after ICSI have similar school performance as children born after IVF?

SUMMARY ANSWER

Children born after ICSI have similar school performance compared to children born after IVF.

WHAT IS KNOWN ALREADY

Studies concerning the cognitive skills of children born after ICSI have shown diverging results.

STUDY DESIGN, SIZE, DURATION

This nationwide, register-based cohort study included all singleton children born after ICSI (n = 6953), IVF (n = 11 713) or spontaneous conception (SC) (n = 2 022 995), in Sweden between 1985 and 2006.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Singleton children born after ICSI were identified in national IVF registers, cross-linked with the Medical Birth Register (MBR), the National Patient Register (NPR) and the Swedish Cause of Death Register (CDR) for characteristics and medical outcomes. Data on school performance, parental education and other parental characteristics were obtained through cross-linking to the National School Registry and to Statistics Sweden. The main control group, which consisted of children born after IVF, was identified in the national IVF registries while the second control group, consisting of children born after SC, was identified from the MBR. Simple and multivariable linear regression was used for analysis of continuous variables, and logistic regression was used for the analysis of binary outcomes. Adjustments were made for sex, year of birth, maternal smoking during pregnancy, parental age, parity, parental region of birth, parental level of education and frozen embryo transfer.

MAIN RESULTS AND THE ROLE OF CHANCE

In the adjusted analyses, there was no significant difference between ICSI and IVF children for total score (adjusted odds ratios (AORs) 1.03; 95% CI −0.22 to 2.28; P = 0.11), specific subjects, qualifying for secondary school (AOR 1.02; 95% CI 0.82–1.26; P = 0.87) or poor school performance (AOR 0.92; 95% CI 0.75−1.14; P = 0.47). In the third grade, children born after ICSI had a significantly lower chance of passing all of the subtests in Mathematics (AOR 0.89; 0.83–0.96; P = 0.002) and Swedish (AOR 0.92; 0.85–0.99; P = 0.02) compared to children born after SC. When cross-linking children with missing data on school performances (2.1% for ICSI, 2.0% for IVF and 2.3% for SC) with the Cerebral Palsy Follow-up Register (CPUP) for cerebral palsy, 2.7% of ICSI children, 5.7% of IVF children and 1.7% of SC children without registered education were found. When cross-linking children with missing data on school performances with the NPR for mental retardation, 29.9% of ICSI children, 32.6% of IVF children and 35.0% of SC children with missing data were registered under such a diagnosis.

LIMITATIONS, REASONS FOR CAUTION

The main limitation was that test scores were missing in a small percentage in both ICSI and IVF children. Although we were able to cross-link this subpopulation with the CPUP and the NPR, these diagnoses only partly explained the missing scores. Other limitations were unmeasured and unknown possible confounders, such as information about infertility diagnoses and indication for ICSI, were not available.

WIDER IMPLICATIONS OF THE FINDINGS

These findings are important to most countries where IVF and ICSI are used since there may be differences in choice of procedure. In recent years, there has been an increasing trend towards using ICSI not only for treatment of male infertility but also when the sperm quality is normal. Our results indicate that the school performance of children born after ICSI is reassuring.

STUDY FUNDING/COMPETING INTEREST(S)

Financial support was received through Sahlgrenska University Hospital (ALFGBG – 70 940), Hjalmar Svensson Research Foundation and Nordforsk, project number 71 450. None of the authors declare any conflict of interest.

TRIAL REGISTRATION NUMBER

N/A

Sixth grade academic achievement among children conceived with IVF: a population-based study in Texas, USA

PURPOSE

To compare academic achievement in reading and mathematics at the end of sixth grade and progress from third to sixth grade by children conceived with in vitro fertilization (IVF) to those conceived naturally.

METHODS

This was a retrospective population-based cohort study of IVF-conceived singleton and twin children who took the 3rd grade and 6th grade public school standardized reading and mathematics testing in Texas.

RESULTS

There were 6623 children with reading scores in both the third and sixth grades and 6374 children with mathematics scores in both the third and sixth grades. Mean (± SE) scaled test scores for IVF and control singleton children for reading were 1544.6 ± 3.4 and 1527.7 ± 1.9, respectively, in third grade and 1701.2 ± 3.6 and 1681.0 ± 2.0, respectively, in sixth grade; for mathematics, the scores were 1564.4 ± 3.7 and 1548.9 ± 2.1, respectively, in third grade and 1774.0 ± 4.2 and 1752.0 ± 2.3, respectively, in sixth grade. In multivariate models, singleton IVF children scored significantly higher than control children in reading and mathematics, averaging 17.7 ± 4.0 points and 20.1 ± 4.1 points higher, respectively, in reading in third and sixth grades and 17.8 ± 4.4 points and 25.0 ± 4.8 points higher, respectively, in mathematics in third and sixth grades.

CONCLUSIONS

Children conceived with IVF and aged 8-9 years and aged 10-12 years performed as well on third and sixth grade reading and mathematics assessments as their counterparts conceived naturally.

How Are They Doing? Neurodevelopmental Outcomes at School Age of Children Born Following Assisted Reproductive Treatments

OBJECTIVE

The purpose of this study was to assess major neurodevelopmental aspects of children conceived by assisted reproductive treatments compared to spontaneously conceived children during the early school years.

MATERIAL & METHODS

In this follow-up study, mothers of 358 children born following assisted reproductive treatments and 401 spontaneously-conceived children were interviewed by telephone regarding their children's health and development, when the children were 7-8 years old. The main outcomes were maternal responses to 4 questionnaires: Developmental Coordination Disorder Questionnaire, Short Sensory Profile, Autism Spectrum Screening Questionnaire, and the Attention-deficit hyperactive disorder (ADHD) Child Symptom Inventory-4 subscale. Mothers reported diagnoses of ADHD and autism spectrum disorder.

RESULTS

No significant differences were found between the groups in Developmental Coordination Disorder Questionnaire or Short Sensory Profile scores upon univariate or multivariable analyses. There was a slightly higher but nonsignificant rate of diagnosed ADHD among children in the assisted reproductive treatment group (9.6% vs 5.5%; P = .18); on multivariable analysis, a nonsignificant increase in ADHD was also found for assisted reproductive treatment children (hazard ratio 1.45, 95% confidence interval 0.81-2.61). Regarding the Child Symptom Inventory-4 criteria for ADHD among the children who had never been diagnosed, there was also a slightly higher but nonsignificant rate among the assisted reproductive treatments compared to spontaneously-conceived children on univariate (2.4% vs 1.8%; P = .50) and multivariable analysis (odds ratio 0.88, 95% confidence interval 0.27-2.86). Autism spectrum disorder diagnosis or Autism Spectrum Screening Questionnaire scores were not significantly different; however, 5 of the 6 children with autism spectrum disorder diagnoses were in the assisted reproductive treatment group.

CONCLUSIONS

Neurodevelopmental measures were similar in both groups, although nonconclusive regarding ADHD and autism spectrum disorder risk. These findings contribute to the knowledge regarding long-term assisted reproductive treatment outcomes.

Ninth-grade school achievement in Danish children conceived following fertility treatment: a population-based cohort study

OBJECTIVE

To assess whether academic achievement among children conceived following fertility treatment is different from that of children born to fertile women while also considering the underlying infertility.

DESIGN

Population-based cohort study.

SETTING

Denmark.

PATIENT(S)

The study population consisted of all 154,536 firstborn, live-born, singleton children in Denmark between 1995 and 2000 who completed their ninth grade with an examination.

INTERVENTION(S)

The Danish Infertility Cohort was used to identify children conceived after fertility treatment (n = 10,099), and information on mean school marks was obtained from Statistics Denmark.

MAIN OUTCOME MEASURE(S)

Linear regression models were used to estimate mean differences (MDs) and 95% confidence intervals (CIs). Multiple logistic regression models were used to estimate odds ratios (OR) and 95% CI of not passing the ninth-grade examination.

RESULTS

The crude overall mean marks for children conceived after the various fertility treatment procedures were in general higher than in children born to fertile women. However, after adjustment for potential confounders, the overall mean marks were statistically significantly lower for children conceived after the various fertility treatment procedures (e.g., any fertility treatment: MD -0.13; 95% CI -0.18, -0.08) compared with children born to fertile women. Further, children conceived after any fertility treatment had a statistically significant lower crude likelihood of not passing the ninth-grade examination (OR 0.66; 95% CI 0.53, 0.81) compared with children born to fertile women, whereas no difference was observed in the confounder adjusted analyses (OR 1.15; 95% CI 0.89, 1.49). When children born to women requiring fertility assistance but without fertility treatment in the index pregnancy were used as a reference group, no differences in the adjusted overall mean marks and the likelihood of not passing the ninth grade with an examination were observed.

CONCLUSION

Our findings indicate that fertility treatment per se is not associated with lower school marks and the likelihood of not passing the ninth grade with an examination. Hence, we suggest that factors related to both fertility problems and cognitive development may more likely explain the slightly lower academic performance (i.e., modest lower mean marks) among children conceived after fertility treatment.

Health and Well-Being Outcomes of Adolescents Conceived Through In Vitro Fertilization and Intracytoplasmic Sperm Injection

What is the perception of health and well-being of adolescents from an assisted reproductive technology (ART) cohort? We conducted a survey, from September 2015 to June 2016, through self-completion questionnaires, on 487 singleton or twin ART-conceived 11- to 15-year-old adolescents, followed up since 1994, as part of an ART cohort. Collected data concerned perinatal characteristics, health indicators and perception, eating habits, behavior, and living standards. A total of 60.6% of the questionnaires were returned and could therefore be analyzed. This concerned 295 adolescents who were representative of the 788 remaining adolescents of our cohort, in terms of type of ART, maternal and perinatal characteristics, but not gender (sex ratio = 0.77). Overall, 15.3% reported chronic diseases, and only 13.3% of them considered that their chronic disease had an impact on their school life. Moreover, 94.2% of adolescents perceived that their health was "excellent" or "good"; 97.3% adolescents had normal weight or were underweight; onset of menstruation was 12 years old (± 1) for girls, age usually reported for puberty in girls; 51.9% declared having regular physical activity, boys more frequently than girls. Moreover, 70.6% of the boys had a sedentary behavior compared to 44.8% of the girls. A total of 73.5% of the adolescents were stressed at school, but school demand was considered high only in 12.2% of cases. Finally, 90% declared to have high life satisfaction. Overall, ART does not appear to have particular effect on the health indicators and behavior of adolescents who participated in the survey except for higher family affluence scale.

Effect of embryo vitrification on the expression of brain tissue proteins in mouse offspring

Vitrification is widely used in assisted reproductive technologies. However, the nervous system of vitrification offspring is of concern, and research on this is lacking. Vitrification-born mice (vitrification group), conventional in vitro fertilization-embryo transfer pregnancy-born mice (IVF group), and natural pregnancy-born mice (control group) were used to study the effects of vitrification of mouse embryos on protein levels in the brain of offspring. Proteins differentially expressed among the three groups were analyzed using proteomic methods, including two-dimensional electrophoresis, mass spectrometry, and bioinformatics analysis. Immunohistochemistry was used to verify the expression of differentially expressed proteins, such as Actb and Actg1, in each group. Twenty differentially expressed proteins in the brain tissue were identified using two-dimensional protein electrophoresis and mass spectrometry. Bioinformatics analysis revealed that these proteins were related to the development of anatomical structure, signal transduction, transport, cell differentiation, and stress response (biological processes) and the binding of molecules in vivo (molecular functions). The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the differentially expressed proteins were involved in 54 pathways, including phagosome, metabolic pathway, apoptosis, and cysteine and methionine metabolism. Thus, embryo vitrification may cause some changes in the mouse brain at the protein level, necessitating further safety assessment.

Cognitive and behavioural outcome of children born after IVF at age 9 years

STUDY QUESTION

Do ovarian stimulation (OS) and the in vitro laboratory procedures affect offsprings' cognitive and behavioural outcome at 9 years?

SUMMARY ANSWER

OS and the in vitro laboratory procedures or the combination of both were not associated with cognitive and behavioural outcome at age 9 years.

WHAT IS KNOWN ALREADY

ART is not associated with an adverse short-term developmental outcome of the offspring, but limited knowledge is available on the offspring's long-term neurodevelopmental condition.

STUDY DESIGN, SIZE, DURATION

A 9-year longitudinal, assessor-blinded, prospective follow-up study of 169 out of 215 singletons (79%) born between March 2005 and December 2006 was performed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Singletons born following IVF or ICSI with OS (n = 57), born after modified natural cycle IVF/ICSI (MNC-IVF/ICSI; n = 46) and born after natural conception to subfertile couples (Sub-NC; n = 66), were assessed at 9 years. This study design, with two ART groups and a subfertile reference group, allows for disentangling the effects of OS and ART procedures on developmental outcome. Cognitive outcome was evaluated with the Wechsler abbreviated scale of intelligence and the NEPSY-II. Behaviour was assessed with the child behaviour checklist (CBCL) and teacher report form (TRF). Univariable analyses and multiple linear regression models were used.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no significant difference in intelligence quotient (IQ) scores between ART groups (mean IQ (95% CI): OS 114.8 (83.2-142.6); MNC 114.0 (90.2-140.8); Sub-NC 115.4 (87.9-141.2), P = 0.746). Multivariable analyses did not reveal a statistically significant association between ART group and total, verbal and performance IQ. CBCL and TRF scores did not differ significantly between ART groups (P = 0.090 and 0.507, respectively). Multivariable analyses did not demonstrate a statistically significant association between ART group and CBCL and TRF total, or internalising and externalising T-scores. No significant correlations between time to pregnancy (TTP)-a proxy for the severity of parental subfertility-and outcome measures were found (Spearman rho between -0.050 and 0.049, NS), which was confirmed with multivariable analyses.

LIMITATIONS, REASONS FOR CAUTION

The attrition rate of 21% may be considered as a limitation of the study; however, after a follow-up period of 9 years, this rate is generally considered acceptable, and there were no significant differences in background characteristics between children with and without follow-up, making an attrition-related selection bias less likely. Another limitation of the study is the relatively small sample size, which could contribute to selection bias, hamper generalizability to the ART population and lead to false negative findings as a result of underpowering. An a priori power analysis on total IQ indicated that the OS-IVF/ICSI and Sub-NC groups should contain 64 children, confirming that our study including 57 and 66 children, respectively, was slightly underpowered.

WIDER IMPLICATIONS OF THE FINDINGS

Our study indicated that OS and the in vitro laboratory procedures or the combination of both and TTP were not associated with cognitive and behavioural outcome at 9 years. These are reassuring results for both parents and clinicians involved in ART.

STUDY FUNDING/COMPETING INTEREST(S)

The study was financially supported by the University Medical Center Groningen (UMCG), two graduate schools of the UMCG (BCN and SHARE) and the Cornelia Stichting. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation or writing of the report. The authors have no conflicts of interest to declare.

Assessment of operant learning and memory in mice born through ICSI

STUDY QUESTION

Are there differences in operant learning and memory between mice born through ICSI and naturally conceived control (CTL) mice?

SUMMARY ANSWER

ICSI females exhibited deficits in the acquisition reward learning relative to CTL females, and ICSI males exhibited deficiencies in discrimination learning and memory relative to CTL males.

WHAT IS KNOWN ALREADY

Some human outcome studies have suggested that ICSI might be associated with an increased risk of certain cognitive disorders, but only one of two behavioral studies with ICSI mouse models have reported differences between ICSI and CTL females. No studies to date have investigated associative learning in ICSI mice.

STUDY DESIGN, SIZE, DURATION

Groups of 36 ICSI mice (18 male, 18 female) and 37 CTL mice (19 male, 18 female) aged 3-6 months were compared in a series of operant learning procedures that assessed acquisition of a new behavior, discrimination learning and memory. In total, 16 ICSI mice (9 male, 7 female) and 17 CTL mice (10 male, 7 female) received follow-up discrimination learning and memory assessments at 12 months of age (6 months after the end of initial training) to evaluate retention and reacquisition of learned performances.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Mice received daily operant learning sessions in experimental chambers in which all stimulus events and the recording of responses were automated. Food rewards were delivered for responding under different conditions of reinforcement, which varied by procedure. Subjects received a successive series of sessions of nose poke acquisition training, discrimination training and the delayed-non-matching-to-position memory procedure. Mixed repeated measures ANOVAs in which the between-subjects factor was group (ICSI vs CTL) and the within-subjects factor was repeated exposures to learning procedures (i.e. sessions) were used to analyze data.

MAIN RESULTS AND THE ROLE OF CHANCE

In comparisons between all mice (i.e. males and females combined), CTL mice exhibited superior performance relative to ICSI in response acquisition (P = 0.03), discrimination (P = 0.001) and memory (P = 0.007). Sex-specific comparisons between the groups yielded evidence of sexual dimorphism. ICSI females exhibited a deficit in acquisition learning relative to CTL females (P < 0.001), but there was not a significant difference between CTL and ICSI males. In the discrimination and memory tasks, ICSI males exhibited deficits relative to CTL males (P = 0.002 and P = 0.02, respectively) but the differences between females in these tasks were not significant. There was no difference in discrimination or memory retention/re-acquisition assessments conducted with mice at 12 months of age. ICSI males and females weighed significantly more than CTL counterparts at all points during the experiment.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The study was not blinded. All learning assessments utilized food reward; other assessments of operant, Pavlovian and nonassociative learning are needed to fully characterize learning in ICSI mice and speculate regarding the implications for cognitive function in humans conceived via ICSI.

WIDER IMPLICATIONS OF THE FINDINGS

Studying learning and memory processes in mouse models have the potential to shed light on ICSI outcomes at the level of cognitive function. Future research should use multiple learning paradigms, assess both males and females, and investigate the effects of variables related to the ICSI procedure. Studying cognitive function in ICSI is an interdisciplinary endeavor and requires co-ordination between researchers at the genetic and psychological levels of analysis.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported, in part, by grants from the NIH (P30GM110767, HD071736 and HD085506 to W.Y.), the Templeton Foundation (61174 to W.Y.) and a New Scholarly Endeavor Grant from the University of Nevada, Reno Office of Research and Innovation (to M.L., Y.W., H.Z., L.H. and W.Y.). The authors declare no competing interests.

Fathers of children conceived using ART have higher cognitive ability scores than fathers of naturally conceived children

STUDY QUESTION

Does paternal cognitive ability differ for children conceived with and without assisted reproductive technology (ART)?

SUMMARY ANSWER

Young fathers of ART conceived children tend to score cognitively below their same-age natural conception (NC) counterparts and older (above 35) fathers of ART conceived children tend to score above.

WHAT IS KNOWN ALREADY

Cognitive ability is a genetically and socially transmitted trait, and If ART and NC children have parents with different levels of this trait, then this would in itself predict systematic differences in child cognitive outcomes. Research comparing cognitive outcomes of children with different modes of conception finds conflicting results, and studies may be influenced by selection and confounding.

STUDY DESIGN, SIZE, DURATION

This is a population-based study based on Norwegian data, combining information from the Medical Birth Registry (births through 2012), military conscription tests (birth cohorts 1955–1977) and the population registry. These data allow us to compare the cognitive ability scores of men registered as the father of an ART-conceived child to the cognitive abilities of other fathers and to average scores in the paternal birth cohorts.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

The population level study included 18 566 births after ART (5810 after ICSI, 12 756 after IVF), and 1 048 138 NC births. It included all Norwegian men who received a cognitive ability score after attending military conscription between 1973 and 1995. This constituted 614 827 men (89.4% of the male birth cohorts involved). An additional 77 650 unscored males were included in sensitivity analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

Paternal cognitive level was assessed using intelligence quotients (IQ) converted from stanine scores on a three-part cognitive ability test with items measuring numeracy, vocabulary and abstract thought (Raven-like matrices). ART fathers averaged 1.95 IQ points above the average of their own birth cohort (P-value &lt; 0.0005) and 1.83 IQ points above NC fathers in their own birth cohort (P &lt; 0.0005). Comparisons of the IQ of ART fathers to those of NC fathers of similar age and whose children were born in the same year, however, found average scores to be more similar (point estimate 0.24, P = 0.023). These low average differences were found to differ substantially by age of fatherhood, with young ART fathers scoring below their NC counterparts and older ART fathers scoring above their NC counterparts.

LIMITATIONS, REASONS FOR CAUTION

We do not have information on maternal cognition. We also lack information on unsuccessful infertility treatments that did not result in a live birth.

WIDER IMPLICATIONS OF THE FINDINGS

Paternal cognitive ability of ART children differs from that of NC children, and this difference varies systematically with paternal age at child birth. Selection effects into ART may help explain differences between ART and NC children and need to be adequately controlled for when assessing causal effects of ART treatment on child outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

This research has also been supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 262700 (Centre for Fertility and Health). It has also been supported by the Research Council of Norway’s Project 236992 (Egalitarianism under pressure? New perspectives on inequality and social cohesion). There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A

Third grade academic achievement among children conceived with the use of in vitro fertilization: a population-based study in Texas

OBJECTIVE

To evaluate if there are differences in standardized testing results at the end of third grade between children conceived with the use of in vitro fertilization (IVF) and those conceived spontaneously.

DESIGN

Retrospective population-based cohort.

SETTING

Texas public school system.

PATIENT(S)

Singleton and twin children 8-9 years of age who took the third-grade public school standardized testing in Texas from 2012 to 2018.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Standardized testing in reading and mathematics.

RESULT(S)

After exclusions, there were 6,970 IVF and 12,690 non-IVF children with reading scores and 6,973 IVF and 12,729 non-IVF children with mathematics scores. IVF children scored significantly higher in reading (singletons: 1,543 ± 2 vs. 1,525 ± 1; twins: 1,534 ± 2 vs. 1,504 ± 5 [mean ± SE]), and mathematics (singletons: 1,566 ± 2 vs. 1,550 ± 1; twins: 1,557 ± 2 vs. 1,529 ± 5). Children of mothers ≥30 years of age scored consistently higher than children of mothers 18-29 years of age. The differences were of similar magnitude between IVF and control children for older ages, but not significant for IVF. Within the IVF group, there were no significant differences between children born from fresh versus froze-thawed embryos.

CONCLUSION(S)

Children of ages 8-9 years who were conceived with the use of IVF performed as well on third-grade reading and math assessments as their counterparts who were conceived spontaneously. We also found consistent racial and ethnic differences, gender differences, and beneficial effects of older maternal age. Because we were not able to adjust adequately for socioeconomic status and other confounding factors, which may explain some of the observed differences, we conclude that there is no negative effect of IVF conception on academic achievement in third grade.

Long-term health of children conceived after assisted reproductive technology

The aim of this narrative review is to summarize the present knowledge on long-term outcome of children born after assisted reproductive technologies (ART). The main outcomes covered are neurodevelopment including cerebral palsy, cognitive development, attention deficit hyperactivity disorder and autism spectrum disease, growth, cardiovascular function, diabetes type 1, asthma, malignancies, and reproductive health. Results have mainly been obtained from systematic reviews/meta-analyses and large registry studies. It has been shown that children born after ART, when restricted to singletons, have a similar outcome for many health conditions as their spontaneously conceived peers. For some outcomes, particularly cardiovascular function and diabetes, studies show some higher risk for ART singletons or subgroup of ART singletons. The fast introduction of new ART techniques emphasizes the importance of continuous surveillance of children born after ART.

In Vitro Fertilization Technology and Child Health

BACKGROUND

Just under 3% of children in Germany, and approximately 6% of children in some other countries, such as Denmark, are now being conceived with the aid of in vitro fertilization (IVF) technology. Alongside the increased risk of organ malformation, there is now evidence for functional abnormalities due to epigenetic modifications.

METHODS

This review is based on pertinent publications retrieved by a literature search on currently known associations of IVF therapy with malformations and functional abnormalities. The potential implications for the treatment of infertility are discussed.

RESULTS

The risk of congenital malformations is approximately one-third higher in children conceived with the aid of IVF technology than in other children; specifically, there is an odds ratio (OR) of 1.29 (95% confidence interval, [1.03; 1.60]) for cardiac malformations, and there is a relative risk (RR) of 1.35 ([1.12; 1.64]) for musculo- skeletal malformations and 1.58 ([1.28; 1.94]) for genitourinary malformations. The risks of preterm birth and low birth weight are, respectively, 1.7 and 1.5 times higher in IVF singleton pregnancies than in non-IVF pregnancies. Cardiovascular changes are the main type of functional disturbance. Some of the risks associated with IVF have decreased in recent years. An association has been revealed between cardiovascular abnormalities and epigenetic modifications; the causes are thought to include not only maternal and paternal factors, but also the IVF techniques that are used. A modification of IVF therapies might lower the risks, but might also lower the success rate.

CONCLUSION

For the well-being of the children to be conceived, IVF therapy should hat cannot be treated by any other means, as the precise causes of the risks of IVF to child health are unclear.

Increased blood pressure and impaired endothelial function after accelerated growth in IVF/ICSI children

STUDY QUESTION

What is the effect of growth velocity (height and weight) in early infancy on metabolic end-points and endothelial function in children born after ART?

SUMMARY ANSWER

Neonatal, infant and childhood growth is positively related to blood pressure in 9-year-old IVF/ICSI offspring, while growth in childhood was negatively associated with endothelial function.

WHAT IS KNOWN ALREADY

Offspring of pregnancies conceived after ART are at risk for later cardiometabolic risk factors. It is well established that early growth is related to numerous later cardiometabolic risk factors such as high blood pressure. This concept is known as the Developmental Origin of Health and Disease theory.

STUDY DESIGN SIZE DURATION

The relation between early growth and later cardiometabolic risk profile was studied in the MEDIUM-KIDS study, a prospective observational cohort study in children born after an IVF/ICSI treatment. In 131 children (48.1% males) at the average age of 9.4 years, cardiometabolic outcomes were assessed and growth data from birth until age 9 years were collected from child welfare centers.

PARTICIPANTS/MATERIALS SETTINGS METHODS

The following cardiometabolic outcomes were assessed: blood pressure, skinfolds, lipid spectrum, hair cortisone and glucose and insulin levels. Data on maximum skin perfusion after transdermal delivery of acetylcholine as a measure of endothelial function were collected.Growth charts were obtained electronically from child welfare centers, which offer free consultations and vaccinations to all Dutch children. At these centers, height and weight are recorded at predefined ages. Growth was defined as z-score difference in weight between two time points. Multivariable linear regression analysis was used to model the relation between growth and cardiometabolic outcomes. The following growth windows were -studied simultaneously in each model: 0-1 month, 1-3 months, 3-6 months, 6-11 months, 11-24 months and 2-6 years. The model was adjusted for height growth in all intervals except for 0-1 month.

MAIN RESULTS AND THE ROLE OF CHANCE

In multivariable linear regression analyses, multiple growth windows were positively associated with blood pressure, for example growth from 2-6 years was significantly related to systolic blood pressure: B = 4.13, P = 0.005. Maximum skin perfusion after acetylcholine was negatively associated with height-adjusted weight gain from 2 to 6 years: B = -0.09 (log scale), P = 0.03. Several growth windows (weight 1-3 months, 3-6 months, 6-11 months, 11-24 months, 2-6 years) were positively linked with total adiposity. Lipids, glucose tolerance indices and cortisone were not related to growth.

LIMITATIONS REASONS FOR CAUTION

This study is of modest size and of observational nature, and we did not include a control group. Therefore, we cannot assess whether the observed associations are causal. It is also not possible to analyze if our observations are specific for, or exacerbated in, the ART population. Ideally, a control group of naturally conceived siblings of IVF/ICSI children should simultaneously be studied to address this limitation and to assess the impact of the ART procedure without the influence of parental (subfertility) characteristics.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this study contribute to our understanding of the reported increased risk for hypertension in ART offspring. We speculate that early, accelerated growth may be involved in the reported increased risk for hypertension in ART offspring, with endothelial dysfunction as a possible underlying mechanism. However, additional research into the mechanisms involved is required.

STUDY FUNDING/COMPETING INTERESTS

The study was financially supported by the March of Dimes, grant number #6-FY13-153. The sponsor of the study had no role in study design, data collection, data analysis, data interpretation or writing of the paper. The authors have no conflict of interest to declare.

TRIAL REGISTRATION NUMBER

NTR4220.

High Dosages of Equine Chorionic Gonadotropin Exert Adverse Effects on the Developmental Competence of IVF-Derived Mouse Embryos and Cause Oxidative Stress-Induced Aneuploidy

Gonadotropins play vital roles in the regulation of female reproductive ability and fertility. Our study aimed to determine the effects of superovulation induced by increasing doses of equine chorionic gonadotropin [eCG; also referred to as pregnant mare serum gonadotropin (PMSG)] on the developmental competence of mouse embryos and on aneuploidy formation during in vitro fertilization (IVF). eCG dose-dependently enhanced the oocyte yield from each mouse. Administration of 15 IU eCG significantly reduced the fertilization rate and the formation of four-cell embryos and blastocysts and increased the risk of chromosome aneuploidy. The IVF-derived blastocysts in the 15 IU eCG treatment group had the fewest total cells, inner cell mass (ICM) cells and trophectoderm (TE) cells. Moreover, more blastocysts and fewer apoptotic cells were observed in the 0, 5, and 10 IU eCG treatment groups than in the 15 IU eCG treatment group. We also investigated reactive oxygen species (ROS) levels and variations in several variables: mitochondrial membrane potential (MMP); active mitochondria; mitochondrial superoxide production; adenosine triphosphate (ATP) content; spindle structures; chromosome karyotypes; microfilament distribution; and the expression of Aurora B [an important component of the chromosomal passenger complex (CPC)], the spindle assembly checkpoint (SAC) protein mitotic arrest deficient 2 like 1 (MAD2L1), and the DNA damage response (DDR) protein γH2AX. Injection of 15 IU eCG increased ROS levels, rapidly reduced MMP, increased active mitochondria numbers and mitochondrial superoxide production, reduced ATP content, increased abnormal spindle formation rates, and induced abnormalities in chromosome number and microfilament distribution, suggesting that a high dose of eCG might alter developmental competence and exert negative effects on IVF-obtained mouse embryos. Additionally, the appearance of γH2AX and the significantly increased expression of Aurora B and MAD2L1 suggested that administration of relatively high doses of eCG caused Aurora B-mediated SAC activation triggered by ROS-induced DNA damage in early mouse IVF-derived embryos for self-correction of aneuploidy formation. These findings improve our understanding of the application of gonadotropins and provide a theoretical basis for gonadotropin treatment.

The effects of intrauterine insemination and single embryo transfer or modified natural cycle in vitro fertilization on offspring's health-Follow-up of a randomized clinical trial

OBJECTIVE

Does ovarian hyperstimulation and/or the in vitro procedure of assisted reproduction affect neurodevelopmental and physical health of the offspring?

STUDY DESIGN

Infertile couples were randomly allocated to intrauterine insemination with controlled ovarian hyperstimulation (IUI-COH), modified natural cycle in vitro fertilization (IVF-MNC) or single embryo transfer IVF (IVF-SET). We compared neurodevelopmental and physical health in childhood (4-7 years). We used age-appropriate questionnaires to assess behavioral problems (Child Behavior Check List (CBCL)) and executive functioning (Behavior Rating Inventory of Executive Function (BRIEF)). We measured body mass index Z-score, waist- and hip-circumference, body fat percentage, blood pressure Z-scores, pulse wave velocity, glucose, insulin, insulin resistance, total cholesterol, high- and low-density lipoprotein cholesterol, triglycerides, and high sensitivity c-reactive protein. We compared groups by analysis of variance.

RESULTS

We examined 191 (57%) of the 333 children born in the study at a mean age of 5.5 years (range 4.0-7.6 years). We found no statistically significant differences between randomization groups in children's neurodevelopmental or physical health indices (all p-values > 0.05). Comparing the outcomes between actual method of conception, including a naturally conceived group, also did not show statistically significant differences.

CONCLUSIONS

Although this follow-up study was not powered on childhood outcomes and limited power due to attrition may have hampered detection of subtle effects, we found no indications of differences in neurodevelopmental and physical health between ovarian hyperstimulation and/or the in vitro procedure of assisted reproduction. Future trials should be powered on child outcomes, and aim to optimize follow-up rates to provide answers that are more definitive.

Epigenetics and Neurological Disorders in ART

About 1–4% of children are currently generated by Assisted Reproductive Technologies (ART) in developed countries. These babies show only a slightly increased risk of neonatal malformations. However, follow-up studies have suggested a higher susceptibility to multifactorial, adult onset disorders like obesity, diabetes and cardiovascular diseases in ART offspring. It has been suggested that these conditions could be the consequence of epigenetic, alterations, due to artificial manipulations of gametes and embryos potentially able to alter epigenetic stability during zygote reprogramming. In the last years, epigenetic alterations have been invoked as a possible cause of increased risk of neurological disorders, but at present the link between epigenetic modifications and long-term effects in terms of neurological diseases in ART children remains unclear, due to the short follow up limiting retrospective studies. In this review, we summarize the current knowledge about neurological disorders promoted by epigenetics alterations in ART. Based on data currently available, it is possible to conclude that little, if any, evidence of an increased risk of neurological disorders in ART conceived children is provided. Most important, the large majority of reports appears to be limited to epidemiological studies, not providing any experimental evidence about epigenetic modifications responsible for an increased risk.

Periconceptional environment and the developmental origins of disease

The concept emerging from Professor David Barker’s seminal research on the developmental origins of later-life disease has progressed in many directions since it was first published. One critical question being when during gestation might environment alter the developmental programme with such enduring consequences. Here, we review the growing consensus from clinical and animal research that the period around conception, embracing gamete maturation and early embryogenesis might be the most vulnerable period. We focus on four types of environmental exposure shown to modify periconceptional reproduction and offspring development and health: maternal overnutrition and obesity; maternal undernutrition; paternal diet and health; and assisted reproductive technology. These conditions may act through diverse epigenetic, cellular and physiological mechanisms to alter gene expression and cellular signalling and function in the conceptus affecting offspring growth and metabolism leading to increased risk for cardiometabolic and neurological disease in later life.

Intellectual Disability in Children Conceived Using Assisted Reproductive Technology

OBJECTIVES

To examine whether children conceived using assisted reproductive technology (ART) have a higher risk of intellectual disability (ID) compared with non-ART-conceived children and describe known causes of ID in these groups.

METHODS

We linked ID and ART data from population-based registers in Western Australia. Our cohort included live births from 1994 to 2002 (n = 210 627) with at least 8 years of follow-up. The prevalence of ID was compared between ART- and non-ART-conceived children, and risk of ID was estimated using Poisson regression with robust SEs. We also stratified by plurality and gestation at delivery.

RESULTS

Children conceived using ART had a small increased risk of ID (risk ratio 1.58; 95% confidence interval 1.19-2.11) even when analyses were restricted to singleton births (risk ratio 1.56; 95% confidence interval 1.10-2.21). The risk of ID was more than doubled for those born very preterm, for severe ID, and after intracytoplasmic sperm injection (ICSI) treatments. Children conceived using ICSI had a greater risk of ID than those conceived using in vitro fertilization and were more likely to have a known genetic cause for ID (27.6% vs 12.9% in vitro fertilization and 11.9% non-ART).

CONCLUSIONS

The risk of ID was increased in children born after ART in Western Australia from 1994 to 2002. More recent cohorts should be examined to assess the impact of important changes in ART clinical practice. Our results are particularly pertinent because multiple embryo transfers are routinely performed in many countries, increasing the risk of preterm birth, and ICSI use rates are high.

Academic performance in adolescents aged 15-16 years born after frozen embryo transfer compared with fresh embryo transfer: a nationwide registry-based cohort study

OBJECTIVE

To assess academic performance in singletons aged 15-16 years conceived after frozen embryo transfer (FET) compared with singletons born after fresh embryo transfer (ET) in Danish cohorts born from 1995 to 2001.

DESIGN

Danish national registry-based cohort study.

SETTING

Danish national registries.

POPULATION

All 6495 singletons conceived after assisted reproductive technology (ART) treatment in Denmark from 1995 to 2001 [FET (n) = 423; fresh ET (n) = 6072].

METHODS

Mean test scores on a national standardised and international comparable grading-scale. Comparisons of test score were first made in univariate analysis (Model 1) and secondly in a multivariate linear model (Model 2) adjusting for relevant reproductive and socio-demographic covariates such as the occupational and educational level of the parents. Sensitivity analyses on FET-IVF (in vitro fertilisation) versus fresh ET-IVF and FET-ICSI (intracytoplasmic sperm injection) versus fresh ET-ICSI were made. Linear mixed models were used to account for the correlation in test scores of siblings for continuous outcome.

MAIN OUTCOME MEASURES

Mean overall test score and test score in Danish, mathematics, English, and physics/chemistry.

RESULTS

Crude and adjusted mean test scores were similar for adolescents conceived after FET compared with fresh ET. The crude mean difference was +0.11 (95% CI -0.11; 0.34), and the adjusted mean difference was +0.12 (95% CI -0.09; 0.34).

CONCLUSIONS

Adolescents conceived after FET had similar academic performance at 15-16 of years of age compared with children conceived after fresh ET.

TWEETABLE ABSTRACT

Using frozen embryos in fertility treatment does not affect school performance in Danish adolescents aged 15-16 years.

No effect of IVF culture medium on cognitive development of 9-year-old children

STUDY QUESTION

Do embryo culture media used during an IVF/ICSI treatment have an effect on cognitive development of singleton IVF children at 9 years of age?

SUMMARY ANSWER

Cognitive development of children born after culture in two different embryo culture media is comparable.

WHAT IS KNOWN ALREADY

Previously, we have shown that the culture medium used in an IVF/ICSI treatment affects birthweight and weight at 2 years of age after alternating assignment to embryo culture in either K-SCICM (Cook) or G1™ Version 3 (Vitrolife). Children with low birthweight are known to have an increased risk for learning disabilities. Data on cognitive development in general of children born after ART are still conflicting, and the only study reporting on the effects of culture medium on cognitive development shows significant differences in cognitive development between two culture medium groups.

STUDY DESIGN SIZE DURATION

In this observational cohort follow-up study (MEDIUM-KIDS), parents of all singletons from our abovementioned study were approached after the ninth birthday of their child to participate in an additional follow-up study. Of the 294 eligible children included in the original study, 119 children (70 Vitrolife and 49 Cook) participated in the current study.

PARTICIPANTS/MATERIALS SETTING METHODS

All follow-up measurements were performed between March 2014 and December 2016. CITO (Dutch Central Institute for Test Development) developed the Dutch pupil monitoring system, which involves nationwide independent, standardized, academic achievement score tests to monitor the child's school performance twice a year at fixed time points from third grade onward. The tests include language skills (vocabulary and orthography), mathematics and reading capability and comprehension. Results from the tests performed between third and sixth grades, expressed as ability scores, were obtained from the school. To investigate school performance development over the years, we used a mixed effects multilevel model. The least complex model with the best fit was selected to analyze whether culture medium affects cognitive development in our cohort. The study had enough power to detect a difference in ability score that reflects at least one performance category between the two groups.

MAIN RESULTS AND THE ROLE OF CHANCE

No differences were seen in baseline characteristics between participants and non-participants (both parental and children characteristics). For all domains, the random intercept model was used. All analyses showed comparable results for the two culture medium groups. No significant differences were observed for any of the cognitive development domains, even after correction for potential confounders. Parental level of education was higher in the IVF group (45%) if compared to the national average level of education (35%), which most likely explains the higher CITO scores for the IVF children if compared to the National ability scores.

LIMITATIONS REASONS FOR CAUTION

A limitation of the study was its pseudo-randomized design and the relatively low participation rate of 40.5%. This and the number of missing data prevent us from drawing robust causal conclusions. However, as this is the first and therewith oldest cohort of children where culture medium was allocated alternatingly and used in a blinded setting, in the same period, with all other conditions identical this study gives up until now the best available evidence.

WIDER IMPLICATIONS OF THE FINDINGS

Our study analyzes the effects of culture medium on school performance of children born after IVF/ICSI in a prospective cohort study. Although further research on long-term academic skills and also on behavior is essential, our results are reassuring and should make parents of children born after IVF/ICSI feel comfortable with their children's cognitive development.

STUDY FUNDING/COMPETING INTERESTS

The study was financially supported by the March of Dimes (Grant no. #6-FY13-153). The sponsor of the study had no role in study design, data collection, data analysis, data interpretation or writing of the report. The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

NTR4220.