Infertility, infertility treatment and psychomotor development: the Danish National Birth Cohort

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.

Frequency, morbidity and equity - the case for increased research on male fertility

Currently, most men with infertility cannot be given an aetiology, which reflects a lack of knowledge around gamete production and how it is affected by genetics and the environment. A failure to recognize the burden of male infertility and its potential as a biomarker for systemic illness exists. The absence of such knowledge results in patients generally being treated as a uniform group, for whom the strategy is to bypass the causality using medically assisted reproduction (MAR) techniques. In doing so, opportunities to prevent co-morbidity are missed and the burden of MAR is shifted to the woman. To advance understanding of men's reproductive health, longitudinal and multi-national centres for data and sample collection are essential. Such programmes must enable an integrated view of the consequences of genetics, epigenetics and environmental factors on fertility and offspring health. Definition and possible amelioration of the consequences of MAR for conceived children are needed. Inherent in this statement is the necessity to promote fertility restoration and/or use the least invasive MAR strategy available. To achieve this aim, protocols must be rigorously tested and the move towards personalized medicine encouraged. Equally, education of the public, governments and clinicians on the frequency and consequences of infertility is needed. Health options, including male contraceptives, must be expanded, and the opportunities encompassed in such investment understood. The pressing questions related to male reproductive health, spanning the spectrum of andrology are identified in the Expert Recommendation.

Assisted reproductive technology and neurodevelopmental outcomes in offspring: a prospective birth cohort study in East China

RESEARCH QUESTION

Is ART associated with adverse neurodevelopmental outcome in 12-month-old offspring compared with those conceived through natural conception?

DESIGN

In this prospective cohort study, 488 infertile women undergoing ART and 1397 women with natural conception were recruited and followed until their offspring were 12 months old. The primary outcome was the neurodevelopment in the offspring. The association between exposure to ART and Gesell developmental scale scores was investigated using multiple linear regression models after adjusting for confounders. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to verify the results.

RESULTS

In total, 18 (3.7%) and 40 (2.9%) children in the ART and natural conception groups, respectively, had been diagnosed with neurodevelopmental delay at 12 months of age. It was found that gross motor, adaptive behaviour, language and total development quotient scores were comparable between the groups. Following multivariate linear regression and IPTW, social behaviour development quotient scores were found to be slightly higher in the ART group than the natural conception group. Higher social behaviour development quotient scores in the ART group were also observed in the male and the singleton subgroups.

CONCLUSIONS

At 12 months, offspring born after ART appeared to have similar motor, language and adaptive behaviour skills, and total development quotient scores, to those born after natural conception. However, social behaviour development in 12-month-old infants was slightly higher in those conceived using ART than in naturally conceived offspring, especially in male or singleton infants. These findings may provide new information in evaluating the potential benefits and risks of ART.

The metabolic health of young men conceived using intracytoplasmic sperm injection

STUDY QUESTION

Is the metabolic health of men conceived using ICSI different to that of IVF and spontaneously conceived (SC) men?

SUMMARY ANSWER

ICSI-conceived men aged 18-24 years, compared with SC controls, showed differences in some metabolic parameters including higher resting diastolic blood pressure (BP) and homeostasis model assessment for insulin resistance (HOMA-IR) scores, although the metabolic parameters of ICSI- and IVF-conceived singleton men were more comparable.

WHAT IS KNOWN ALREADY

Some studies suggest that IVF-conceived offspring may have poorer cardiovascular and metabolic profiles than SC children. Few studies have examined the metabolic health of ICSI-conceived offspring.

STUDY DESIGN, SIZE, DURATION

This cohort study compared the metabolic health of ICSI-conceived men to IVF-conceived and SC controls who were derived from prior cohorts. Participants included 121 ICSI-conceived men (including 100 singletons), 74 IVF-conceived controls (all singletons) and 688 SC controls (including 662 singletons).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Resting systolic and diastolic BP (measured using an automated sphygmomanometer), height, weight, BMI, body surface area and fasting serum metabolic markers including fasting insulin, glucose, total cholesterol, high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol, triglycerides, highly sensitive C-reactive protein (hsCRP) and HOMA-IR were compared between groups. Data were analysed using multivariable linear regression adjusted for various covariates including age and education level.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjusting for covariates, compared to 688 SC controls, 121 ICSI-conceived men had higher diastolic BP (β 4.9, 95% CI 1.1-8.7), lower fasting glucose (β -0.7, 95% CI -0.9 to -0.5), higher fasting insulin (ratio 2.2, 95% CI 1.6-3.0), higher HOMA-IR (ratio 1.9, 95% CI 1.4-2.6), higher HDLC (β 0.2, 95% CI 0.07-0.3) and lower hsCRP (ratio 0.4, 95% CI 0.2-0.7) levels. Compared to 74 IVF-conceived singletons, only glucose differed in the ICSI-conceived singleton men (β -0.4, 95% CI -0.7 to -0.1). No differences were seen in the paternal infertility subgroups.

LIMITATIONS, REASONS FOR CAUTION

The recruitment rate of ICSI-conceived men in this study was low and potential for recruitment bias exists. The ICSI-conceived men, the IVF-conceived men and SC controls were from different cohorts with different birth years and different geographical locations. Assessment of study groups and controls was not contemporaneous, and the measurements differed for some outcomes (BP, insulin, glucose, lipids and hsCRP).

WIDER IMPLICATIONS OF THE FINDINGS

These observations require confirmation in a larger study with a focus on potential mechanisms. Further efforts to identify whether health differences are due to parental characteristics and/or factors related to the ICSI procedure are also necessary.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by an Australian National Health and Medical Research Council Partnership Grant (NHMRC APP1140706) and was partially funded by the Monash IVF Research and Education Foundation. S.R.C. was supported through an Australian Government Research Training Program Scholarship. R.J.H. is supported by an NHMRC project grant (634457), and J.H. and R.I.M. have been supported by the NHMRC as Senior and Principal Research Fellows respectively (J.H. fellowship number: 1021252; R.I.M. fellowship number: 1022327). L.R. is a minority shareholder and the Group Medical Director for Monash IVF Group, and reports personal fees from Monash IVF Group and Ferring Australia, honoraria from Ferring Australia and travel fees from Merck Serono and MSD and Guerbet; R.J.H. is the Medical Director of Fertility Specialists of Western Australia and has equity in Western IVF; R.I.M. is a consultant for and shareholder of Monash IVF Group and S.R.C. reports personal fees from Besins Healthcare and nonfinancial support from Merck outside of the submitted work. The remaining authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Parental fecundability and neurodevelopmental delays and difficulties in offspring

BACKGROUND

Impaired neurodevelopment is reported among children conceived by assisted reproductive technologies (ART). However, this might be explained by conditions underlying parental subfecundity, rather than the ART procedure.

METHODS

We examined associations of parental time-to-pregnancy (TTP) and conception by ART with neurodevelopmental traits up to 8 years of age, including motor and language skills, social delays and difficulties, and inattention-hyperactivity, among 92 142 singletons participating in the Norwegian Mother, Father and Child Cohort Study (MoBa). Mothers reported TTP and neurodevelopmental traits through questionnaires. Mean differences in standardized neurodevelopmental traits were estimated using linear regression, adjusting for maternal age, parity, educational level, body mass index and smoking, and paternal age.

RESULTS

A longer TTP was associated with decreased language skills and motor skills at 6, 18 and 36 months (P-values for trend ≤0.01), prosocial skills delay at 36 months (P-values for trend ≤0.001) and increased scores for inattention-hyperactivity traits at all ages up to 8 years (P-values for trend from 0.06 to 0.01). Effect sizes were small, ranging between 0.03 and 0.05 difference in the standardized neurodevelopmental scores. Estimates for ART were imprecise, but there were no differences between children conceived by ART and naturally conceived children of subfecund parents (TTP ≥12 months).

CONCLUSIONS

Longer parental TTP is modestly but robustly associated with offspring neurodevelopmental delays and difficulties, with no added impact of ART. Future studies should investigate the underlying causes of-or aspects related to-parental subfecundity which might explain the association with offspring neurodevelopmental delays and difficulties.

Association between maternal infertility treatment and child neurodevelopment: findings from the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study in Miyagi and Iwate Prefectures, Japan

OBJECTIVES

This study aimed to examine the association between infertility treatment and neurodevelopment in children at 2 and 3.5 years of age.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

The study population consisted of mother-child pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study in Miyagi and Iwate Prefectures, Japan. Pregnant women were recruited in obstetric clinics or hospitals and their children were followed up by the questionnaire.

OUTCOME MEASURES

The children's neurodevelopmental outcomes were assessed at 2 and 3.5 years of age using the Ages and Stages Questionnaire, third edition (ASQ-3), which consists of questions on five developmental domains. We performed a multivariate logistic regression analysis of the association between infertility treatment (including ovulation induction (OI), artificial insemination with husband's sperm (AIH) and assisted reproductive technology (ART)) and the clinical range of ASQ-3.

RESULTS

Of 9655 mother-child pairs, 273 (2.8%) and 487 (5.0%) were conceived through OI/AIH and ART, respectively. The odds of having developmental delays at 2 years of age were higher in children conceived through OI/AIH (OR, 1.36; 95% CI 1.00 to 1.85) and ART (OR, 1.36; 95% CI 1.07 to 1.72) than in those conceived naturally. Additionally, OI/AIH and ART were significantly associated with communication (OR, 1.93; 95% CI 1.25 to 2.98) and gross motor (OR, 1.50; 95% CI 1.08 to 2.09) delays, respectively. There were no statistically significant differences in the odds of having developmental delays at 3.5 years of age in children conceived through OI/AIH (OR, 1.13; 95% CI 0.79 to 1.61) and ART (OR, 1.03; 95% CI 0.78 to 1.37).

CONCLUSION

In this study, we found a significant association between infertility treatment and children's neurodevelopment at 2 years of age, whereas no statistically significant differences were found at 3.5 years of age.

Embryo morphologic quality in relation to the metabolic and cognitive development of singletons conceived by in vitro fertilization and intracytoplasmic sperm injection: a matched cohort study

BACKGROUND

Embryos with higher morphologic quality grading may have a greater potential to achieve clinical pregnancy that leads to a live birth regardless of the type of cleavage-stage embryos or blastocysts. Few studies have investigated the impacts of embryo grading on the long-term health of the offspring.

OBJECTIVE

This pilot study aimed to examine the associations between embryo morphologic quality and the physical, metabolic, and cognitive development of singletons conceived by in vitro fertilization and intracytoplasmic sperm injection at preschool age.

STUDY DESIGN

This matched cohort study included singletons born to infertile couples who underwent fresh cleavage-stage embryo transfer cycles with good- or poor-quality embryos from 2014 to 2016 at the reproductive center of the Women's Hospital, School of Medicine, Zhejiang University. A total of 144 children, aged 4 to 6 years, participated in the follow-up assessment from 2020 to 2021, and the response rate of poor-quality embryo offspring was 39%. Singletons in the good-quality embryo group were matched with singletons in the poor-quality embryo group at a 2:1 ratio according to the fertilization method and the children's age (±1 year). We measured the offspring's height, weight, body mass index, blood pressure, thyroid hormone levels, and metabolic indicators. Neurodevelopmental assessments were performed using the Chinese version of the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition, and the Adaptive Behavior Assessment System, Second Edition. We also collected data from the medical records. A linear regression model was used to analyze the association between embryo morphologic quality and offspring health outcomes.

RESULTS

A total of 48 singletons conceived with poor-quality embryo transfer and 96 matched singletons conceived with good-quality embryo transfer were included in the final analysis. Age, sex, height, weight, body mass index, blood pressure, thyroid function, and metabolic indicators were comparable between the 2 groups. After adjustment for potential risk factors by linear regression model 1 and model 2, poor-quality embryo offspring exhibited a tendency toward higher free thyroxine levels than offspring of good-quality embryo transfers (beta, 0.22; 95% confidence interval, 0.09-0.90; beta, 0.22; 95% confidence interval, 0.09-0.91, respectively), but this difference was not clinically significant. Regarding neurodevelopmental assessments, there was no difference in the full-scale intelligence quotient based on the Wechsler Preschool and Primary Scale of Intelligence (109.96±12.42 vs 109.60±14.46; P=.88) or the general adaptive index based on the Adaptive Behavior Assessment System (108.26±11.70 vs 108.08±13.44; P=.94) between the 2 groups. The subindices of the 2 tests were also comparable. These findings remained after linear regression analysis.

CONCLUSION

At 4 to 6 years of age, singletons born from poor-quality embryo transfers have comparable metabolic and cognitive development as those born from good-quality embryo transfers using fresh cleavage-stage embryos. The results of this pilot study indicate that poor-quality embryos that can survive implantation and end in live birth are likely to have a developmental potential comparable to that of good-quality embryos.

Effect of medically assisted reproduction (MAR) and pregnancy planning on Bayley-III Screening Test subscales in preterm infants at 12 months of corrected age: a cross-sectional study

Background

The association between medically assisted reproduction and pregnancy planning on overall developmental outcomes of infants has been studied in relatively few studies. The availability of accurate tools for the early detection of developmental delays is a major issue. The purpose of this study is describing the average neurodevelopment of preterm infants and assessing the association between medically assisted reproduction, pregnancy planning and neurodevelopmental outcomes among Hungarian preterm infants.

Methods

Cross-sectional study of preterm infants with gestational age < 37 weeks (N = 171) who underwent developmental assessment using Bayley-III Screening Test (Bayley Scales of Infant and Toddler Development Screening Test – Third Edition) in five developmental domains (cognitive, receptive and expressive language, fine and gross motor) at 12 months of corrected age. We examined the developmental pattern of infants and the potential associations between medically assisted reproduction, pregnancy planning and Bayley-III Screening Test subscales. Information on the mode of conception and pregnancy planning was obtained through parental anamnesis.

Results

Concerning the risk for developmental delay, the language and motor subscales were the most affected. Examination of the mode of conception and developmental outcomes revealed higher neurodevelopmental skills in infants who were conceived through medically assisted reproduction. Significantly lower cognitive, receptive and expressive language skills were found to be associated with unplanned pregnancies. Multi-way analysis of variance was conducted in order to assess the impact of the mode of conception and pregnancy planning on subscales.

Conclusions

We cannot unambiguously conclude that MAR and pregnancy planning had a solely positive effect on the development of preterm infants at 12 months of corrected age, but our results are vital for the design and implementation of further research.

Neurological development in 36‐month‐old children conceived via assisted reproductive technology: The Japan Environment and Children's Study

Purpose

This study aimed to investigate neurodevelopment in children conceived via in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with several types of embryo transfers.

Methods

We analyzed data for 77 928 children and their mothers included in a Japanese birth cohort study. Among the included children, 4071 were conceived via IVF, while 1542 were conceived via ICSI. Neurodevelopmental delay at the age of 3 years was assessed using the Japanese version of the Ages and Stages Questionnaires, 3rd edition.

Results

In the crude model, the odds ratios for developmental delay in 1–4 domains were higher among children conceived via IVF, ICSI, and non‐ART (ovulatory induction or intrauterine insemination) than in spontaneously conceived children. After adjusting for parental background factors and the child's sex, there were no differences in the risk of developmental delay when comparing singletons conceived by IVF, ICSI, or non‐ART and those conceived spontaneously. Higher odds ratios for developmental delay in one domain were observed in singleton girls conceived via IVF when compared with those who were spontaneously conceived.

Conclusion

Most cases of developmental delay may be associated with multiple pregnancies and factors related to infertility, such as parental age, irrespective of the use of ART.

Reproductive function in men conceived with in vitro fertilization and intracytoplasmic sperm injection

OBJECTIVE

To determine the semen quality and reproductive hormones of men conceived by in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) compared with men conceived without assisted reproductive technology (ART).

DESIGN

Cohort study.

SETTING

IVF centers in Victoria and the Western Australian Raine Study.

PATIENT(S)

Men conceived with IVF/ICSI and men conceived without ART aged 18-25 years.

INTERVENTION(S)

Clinical review.

MAIN OUTCOME MEASURE(S)

The primary outcome was the prevalence of severe oligozoospermia (sperm concentration, <5 million/mL). The secondary outcomes were total sperm count, total and progressive motility, total motile count, normal morphology, and serum testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

RESULTS

There was no difference in the prevalence of severe oligozoospermia between 120 men conceived with IVF/ICSI and 356 men conceived without ART (9% vs. 5.3%). Men conceived with IVF/ICSI had similar sperm concentration, total sperm count, and total motile count but lower mean total (55.3% vs. 60.6%) and progressive (44.7% vs. 53.9%) sperm motility with higher mean normal morphology (8.5% vs. 5.4%). Differences in progressive motility (ß, -9.9; 95% confidence interval [CI], -16.7 - -3.0), normal morphology (ß, 4.3; 95% CI, 3.0-5.7), and proportion with abnormal morphology (adjusted odds ratios, 0.1; 95% CI, 0.04-0.5) remained significant after adjusting for confounders. Men conceived with IVF/ICSI had lower mean FSH (3.3 IU/L) and LH (3.9 IU/L) levels and higher mean testosterone levels (19.1 nmol/L) than controls (4.2 IU/L, 11.0 IU/L, and 16.8 nmol/L).

CONCLUSION

This study of men conceived with IVF/ICSI found similar sperm output to men conceived without ART. Overall, the results are reassuring.

The Principle of "Damage Exclusion" as a Benchmark in Catholic Discussions of Homologous Artificial Insemination

The Catholic perspective rejects assisted human reproduction techniques, but the morality of artificial insemination (AI) is open for discussion. This article aims to analyze the morality of AI from a new angle, namely whether these interventions exclude all possibility of damaging the human embryo and the offspring's health. The scientific evidence about the children's health who are born through AI allows us to affirm that the procedures do not comply with the principle of damage exclusion: AI does not exclude all possibility of damaging the embryo and impacting the health and exposure to disease of the offspring born through these techniques.

Parent perspective on childhood development after assisted reproductive technology: A national survey

Context:

There is limited understanding about parent perspectives of newborn development after assisted reproductive technology (ART). The use of ART is known to increase the risk of premature delivery and low birth weight. Both of these factors are associated with developmental delay. To our knowledge, no study has investigated how parents perceive their child's development after use of ART.

Aims:

To investigate how the parent perspective of childhood development after ART use compares to the parent perspective of spontaneously conceived children.

Settings and Design:

This is a digital survey collecting data on parent perspective of newborn development after ART and spontaneous conception.

Subjects and Methods:

Invitation to participate was sent via E-mail to users of a (Ovia Health's) mobile parenting application (Ovia Parenting). Surveys were collected from August 30, 2018, to September 12, 2018, and a total of 1881 surveys were collected.

Statistical Analysis Used:

Analysis was performed with Chi-square cross-tabulations and ANOVA.

Results:

Overall, 13,600 (12%) of users who were delivered the E-mail engaged with the content. Of those users, 2739 (20%) initiated the survey and 1881 (69%) completed the survey and were included in the analyses. When comparing spontaneous conception to ART, parents reported similar developmental milestones at most ages. A significant difference existed at 12 months where those who had used ART were more likely to report their child met all milestones. This difference did not persist for subsequent ages.

Conclusions:

From the parent perspective, children conceived using ART methods should be expected to meet the same age-based developmental milestones as their spontaneously conceived peers.

Association between peri-conceptional bisphenol A exposure in women and men and time to pregnancy-The HOPE study

BACKGROUND

Bisphenol A (BPA) is a non-persistent endocrine-disrupting chemical with nearly ubiquitous, involuntary exposure. Previous studies have shown that BPA causes reproductive dysfunction in animal models, but there are limited data regarding the effects of BPA exposure on time to pregnancy (TTP) in humans.

OBJECTIVE

To evaluate whether peri-conceptional BPA exposure of women and men is associated with couples' TTP.

METHODS

A total of 164 heterosexual couples (164 women; 163 men) who have available BPA information as well as time to pregnancy from the Home Observation of Peri-conceptional Exposures (HOPE) Study were included and were followed up to 12 months. Women collected first-morning urine samples starting at the beginning of the fertile window and continued until the onset of menses or 18 days after the estimated day of ovulation (EDO+18 days). The time to pregnancy (TTP) after the enrolment was self-reported and used for the analysis. Discrete-time Cox proportional hazards models were performed to generate fecundability odds ratio (FOR) between BPA and TTP after adjusting for education and age, accounting for right censoring and prior number of cycles trying to conceive.

RESULTS

Among 164 couples, 125 couples became pregnant during the study. There was no association between TTP and peri-conceptional BPA exposure for both men (FOR 1.02, 95% CI 0.72, 1.47) and women (FOR 1.07, 95% CI 0.75, 1.53) after adjusting for education and age.

CONCLUSIONS

No association was found between peri-conceptional BPA exposure and fecundability in this preconception cohort of relatively young, healthy pregnancy planners.

Epigenetically regulated imprinted gene expression associated with IVF and infertility: possible influence of prenatal stress and depression

PURPOSE

Despite the growing body of research implying an impact of in vitro fertilization (IVF) on imprinted genes and epigenetics, few studies have examined the effects of underlying subfertility or prenatal stress on epigenetics, particularly in terms of their role in determining infant birthweights. Both subfertility and prenatal stressors have been found to impact epigenetics and may be confounding the effect of IVF on epigenetics and imprinted genes. Like IVF, both of these exposures-infertility and prenatal stressors-have been associated with lower infant birthweights. The placenta, and specifically epigenetically regulated placental imprinted genes, provides an ideal but understudied mechanism for evaluating the relationship between underlying genetics, environmental exposures, and birthweight.

METHODS AND RESULTS

In this review, we discuss the impacts of IVF and infertility on birthweight, epigenetic mechanisms and genomic imprinting, and the role of these mechanisms in the IVF population and discuss the role and importance of the placenta in infant development. We then highlight recent work on the relationships between infertility, IVF, and prenatal stressors in terms of placental imprinting.

CONCLUSIONS

In combination, the studies discussed, as well as two recent projects of our own on placental imprinted gene expression, suggest that lower birthweights in IVF infants are secondary to a combination of exposures including the infertility and prenatal stress that couples undergoing IVF are experiencing. The work highlighted herein emphasizes the need for appropriate control populations that take infertility into account and also for consideration of prenatal psychosocial stressors as confounders and causes of variation in IVF infant outcomes.

Association of four imprinting disorders and ART

Background

Human-assisted reproductive technologies (ART) are a widely accepted treatment for infertile couples. At the same time, many studies have suggested the correlation between ART and increased incidences of normally rare imprinting disorders such as Beckwith-Wiedemann syndrome (BWS), Angelman syndrome (AS), Prader-Willi syndrome (PWS), and Silver-Russell syndrome (SRS). Major methylation dynamics take place during cell development and the preimplantation stages of embryonic development. ART may prevent the proper erasure, establishment, and maintenance of DNA methylation. However, the causes and ART risk factors for these disorders are not well understood.

Results

A nationwide epidemiological study in Japan in 2015 in which 2777 pediatrics departments were contacted and a total of 931 patients with imprinting disorders including 117 BWS, 227 AS, 520 PWS, and 67 SRS patients, were recruited. We found 4.46- and 8.91-fold increased frequencies of BWS and SRS associated with ART, respectively. Most of these patients were conceived via in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), and showed aberrant imprinted DNA methylation. We also found that ART-conceived SRS (ART-SRS) patients had incomplete and more widespread DNA methylation variations than spontaneously conceived SRS patients, especially in sperm-specific methylated regions using reduced representation bisulfite sequencing to compare DNA methylomes. In addition, we found that the ART patients with one of three imprinting disorders, PWS, AS, and SRS, displayed additional minor phenotypes and lack of the phenotypes. The frequency of ART-conceived Prader-Willi syndrome (ART-PWS) was 3.44-fold higher than anticipated. When maternal age was 37 years or less, the rate of DNA methylation errors in ART-PWS patients was significantly increased compared with spontaneously conceived PWS patients.

Conclusions

We reconfirmed the association between ART and imprinting disorders. In addition, we found unique methylation patterns in ART-SRS patients, therefore, concluded that the imprinting disorders related to ART might tend to take place just after fertilization at a time when the epigenome is most vulnerable and might be affected by the techniques of manipulation used for IVF or ICSI and the culture medium of the fertilized egg.

Electronic supplementary material

The online version of this article (10.1186/s13148-019-0623-3) contains supplementary material, which is available to authorized users.

IVF procedures are not, but subfertility is associated with neurological condition of 9-year-old offspring

In vitro fertilization (IVF) is not associated with neurological abnormalities in offspring's early childhood. Yet, it is unclear whether this is also true for school age. Neither do we know the role of parental subfertility in offspring's neurological development. The present study examined neurological condition at 9 years of 57 singletons born after controlled ovarian hyperstimulation IVF (COH-IVF), 46 singletons born after modified natural cycle IVF (MNC-IVF) and 66 singletons born to subfertile parents after natural conception (Sub-NC). To assess the effect of subfertility, the groups were pooled to form a subfertile group, and compared with a prospectively followed fertile reference group (n = 282). The sensitive Minor Neurological Dysfunction (MND) examination was used, resulting in the detailed Neurological Optimality Score (NOS) and the prevalence of the clinically relevant complex MND. Neurological condition of the three subfertile groups did not differ significantly: median NOS was 53 in each subfertile group and the prevalence of complex MND in the three subfertile groups was 30%, 37% and 36%, respectively. However, the NOS was lower and the prevalence of complex MND higher in children born to subfertile couples than in children of fertile couples (adjusted mean difference [95% CI]: -4.48 [-5.53 to -3.42]) and adjusted OR [95% CI]: 5.13 [2.60-10.16], respectively). We conclude that ovarian hyperstimulation, in vitro procedures, and the combination of both were not associated with a less favourable neurological outcome of 9-year-old singletons. However, the presence of parental subfertility was associated with less favourable neurological outcome of offspring at 9 years follow up.

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.

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

STUDY QUESTION

Does fertility treatment influence cognitive ability in school aged children, and does the impact vary with the type of treatment?

SUMMARY ANSWER

The available high-quality evidence indicates that specific treatments may give rise to different effects on cognitive development, with certain treatments, including ICSI, associated with cognitive impairment.

WHAT IS KNOWN ALREADY

Previous reviews of the literature concerning cognitive outcomes among children conceived with medical assistance have concluded that study findings are generally 'reassuring', but limited attention has been paid to the quality of this research. In addition, no review has separately assessed the range of treatment modalities available, which vary in invasiveness, and thus, potentially, in their effects on developmental outcomes.

STUDY DESIGN, SIZE, DURATION

A systematic review was undertaken. We searched PubMed, PsycINFO and the Educational Resources Information Centre database to identify English-language studies published up until 21 November 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Two authors independently reviewed identified articles, extracted data and assessed study quality. Studies were eligible if they assessed cognitive development from age 4 years or more, among children conceived with fertility treatment compared with either children conceived naturally or children born from a different type of fertility treatment. Where available, data were extracted and reported separately according to the various components of treatment (e.g. mode of fertilization, embryo freezing, etc.). Risk of bias was assessed using the Newcastle-Ottawa Scale, with a score ≥7/9 indicative of high quality.

MAIN RESULTS AND THE ROLE OF CHANCE

The search identified 861 articles, of which 35 were included. Of these, seven were rated high quality. Most studies (n = 22) were subject to selection bias, due to the exclusion of children at increased risk of cognitive impairment. Among high-quality studies, there was no difference in cognitive outcomes among children conceived with conventional IVF and those conceived naturally. Findings among high-quality studies of children conceived with ICSI were inconsistent: when compared with children conceived naturally, one study reported lower intelligence quotient (IQ; 5-7 points, on average) among ICSI children whereas the remaining two high-quality studies reported no difference between groups. Furthermore, among the three high-quality studies comparing children conceived with ICSI compared with conventional IVF, one reported a significant increase in the risk of mental retardation, one reported a small difference in IQ (3 points lower, on average) and one no difference at all. There were scant studies examining exposure to embryo freezing, or less invasive treatments such as ovulation induction without IVF/ICSI.

LIMITATION, REASONS FOR CAUTION

Most existing studies had methodological limitations including selection bias and/or failure to address confounding by family background. In addition, a meta-analysis could not be performed due to heterogeneity in the assessment of cognitive outcomes. These factors impeded our ability to synthesize the evidence and draw reliable conclusions.

WIDER IMPLICATIONS OF THE FINDINGS

The conflicting findings among studies of children conceived with ICSI require clarification, in light of the increasing use of this technique for reasons other than male-factor infertility. Further population-based studies are needed that utilize contemporary data to examine specific aspects of treatment and combinations of techniques (e.g. ICSI with frozen embryo cycles). Importantly, studies should include the complete group of children exposed to treatment.

STUDY FUNDING/COMPETING INTEREST(S)

A.R.R. is supported by a Career Development Fellowship from the National Health and Medical Research Council of Australia. L.J.M. is funded by a fellowship from the Heart Foundation of Australia. The authors declare there are no competing interests.

TRIAL REGISTRATION NUMBER

Not applicable.

Neurodevelopmental Outcomes After Assisted Reproductive Technologies

OBJECTIVE

To compare children's cognitive, motor, and language development at 2 years of age after assisted reproductive technologies (ARTs) relative to natural conception.

METHODS

The 3D-Study (2010-2012) is a prospective cohort study, which sought to improve the understanding among perinatal events, obstetric outcomes, and child development. A total of 2,366 pregnant women were recruited, of whom 278 conceived with ART: ovarian stimulation, intrauterine sperm insemination, in vitro fertilization, intracytoplasmic sperm injection, or in vitro maturation. Natural conception was defined as the unassisted establishment of pregnancy. Cognitive, motor, and language neurodevelopmental outcomes were compared between ART and natural conception groups at 24 months using the Bayley Scales of Infant and Toddler Development, 3rd edition, and the MacArthur-Bates Communicative Development Inventories. Adjusted linear regression models evaluated the effect of ART on neurodevelopmental outcomes using natural conception as a reference.

RESULTS

A total of 175 children in the ART group (62.9%) and 1,345 children in the natural conception group (64.4%) underwent neurodevelopmental assessment at 24 months postpartum. After adjusting for relevant confounders, children born after ART showed no difference in Bayley scales' cognitive scores (B1 [standard error]=-1.60 [0.9], 95% confidence interval [CI] -3.36 to 0.16), composite motor scores (B1 [standard error]=-1.33 [1.0], 95% CI -3.29 to 0.63), or MacArthur-Bates language scores (B1 [standard error]=-0.28 [2.1], 95% CI -4.39 to 3.83). No difference was observed when independent ART techniques were compared nor when comparing in vivo (ovarian stimulation or intrauterine insemination) or in vitro (in vitro fertilization, intracytoplasmic sperm injection, or in vitro maturation) techniques (P>.05).

CONCLUSION

Children born after ART had similar cognitive, motor, and language development as children born after natural conception at 2 years of age. These findings may be useful in the clinical counseling of patients undergoing ART.

Reduced Intellectual Ability in Offspring of Ovarian Hyperstimulation Syndrome: A Cohort Study

Background

Ovarian hyperstimulation syndrome (OHSS), a complication of ovarian stimulation, has various adverse effects on both pregnant women and their offspring. However, whether OHSS will affect intellectual ability in offspring is still unknown.

Methods

We recruited 86 Chinese children born to OHSS women and 172 children conceived with non-OHSS In Vitro Fertilization (IVF) in this cohort study. Their intellectual ability was assessed according to the Revised Chinese Version of the Wechsler Intelligence Scale for Children (C-WISC). Verbal Intelligence Quotient (VIQ), Performance Intelligence Quotient (PIQ), and Full Intelligence Quotient (FIQ) were calculated. The investigation was registered in Chinese Clinical Trial Registry (ChiCTR-SOC-16009555).

Findings

OHSS offspring scored less on C-WISC (mean (standard deviation [SD]): (VIQ = 92.7 (14.7), PIQ = 108.9 (13.1), FIQ = 100.6 (13.4)) compared with non-OHSS IVF offspring (VIQ = 100.1 (13.2), PIQ = 113.7 (10.8), FIQ = 107.4 (11.5)). The prevalence of low IQ (< 80) children was 4.7 times higher in OHSS offspring compared with non-OHSS offspring. Maternal estradiol level on hCG administration day was negatively associated with FIQ in offspring.

Interpretation

OHSS offspring displayed reduced intellectual ability. Prenatal estradiol exposure might be involved in underlying mechanism.

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Young children born to OHSS women displayed the lower IQ than non-OHSS IVF children.

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Maternal serum estradiol level on hCG administration day was negatively correlated with IQ of offspring.

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The prevalence of low IQ(<80) children was 4.7 times higher in OHSS offspring.

Ovarian hyperstimulation syndrome (OHSS) is a complication of assisted reproductive technologies. We discovered that children of OHSS mothers displayed reduced intelligence quotient (IQ). This reduction might be associated with higher estradiol level during early pregnancy. Clinician should use ovarian stimulation therapy wisely to avoid OHSS.

Use of Intracytoplasmic Sperm Injection and Birth Outcomes in Women Conceiving through In Vitro Fertilization

BACKGROUND

Despite questionable evidence of benefits over conventional in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) use has markedly increased in recent decades among couples without male factor infertility. We assessed the frequency of ICSI use and its effect on birth outcomes.

METHODS

A retrospective cohort study was conducted in 141 030 women conceiving through IVF using 2006-2010 data from the Society for Assisted Reproductive Technology (SART).

RESULTS

Between 2006 and 2010, overall ICSI use in women conceiving through IVF increased from 68.9% to 73.1%. This increase was greater among women without male factor infertility (53.0-59.2%) than in women with male factor infertility (92.0-93.4%). Women conceiving through IVF with and without ICSI had similar rates of multiple pregnancy, preterm delivery, stillbirth, and neonatal death. However, ICSI pregnancies were associated with an increased risk of birth defects over conventional IVF (3.0% for ICSI vs. 2.5% for conventional IVF; adjusted odds ratio (OR) 1.2, 95% confidence interval (CI) 1.2, 1.3). These increases were observed in both women conceiving through ICSI with male factor infertility (3.2% vs. 2.5%; OR 1.4, 95% CI 1.3, 1.5) and without male factor infertility (2.7% vs. 2.5%; OR 1.1, 95% CI 1.1, 1.2).

CONCLUSIONS

Higher rates of birth defects were observed among women conceiving through ICSI. Since approximately half of all ICSI procedures are performed in couples without male factor infertility, ICSI may be overused in practice.

Childhood psychopathology in children of women with eating disorders

OBJECTIVE

We aimed to investigate the effect of maternal eating disorders (ED) on childhood psychopathology, early delays in cognitive, motor and language development, mother and child relationship, and child temperament in a community-based cohort: the Danish National Birth Cohort (DNBC).

METHOD

Data were obtained prospectively on 48 403 children at 18 months and 46 156 children at 7 years. Data on cognitive, motor and language development, temperament and attachment were obtained at 18 months; data on child psychopathology were obtained at 7 years of age, using the Strengths and Difficulties Questionnaire (SDQ). Children of mothers with lifetime diagnosis of anorexia nervosa (AN, n = 931), lifetime diagnosis of bulimia nervosa (BN, n = 906) and both (AN & BN = 360) were compared to children of mothers without an ED (n = 46 206).

RESULTS

Girls of women with lifetime AN had higher odds of having emotional problems, and girls of women with lifetime BN of having conduct problems compared with children of healthy women. Boys of women with lifetime AN had higher odds of total, emotional and conduct problems; boys of women with lifetime BN had higher odds of total, conduct, hyperactivity and peer difficulties compared to children of women without an ED. Boys of women with lifetime AN and BN had higher odds of total, emotional and peer problems compared to children of healthy women.

CONCLUSION

Maternal ED is associated with childhood psychopathology in both boys and girls. Boys seemed at higher risk for psychopathology in this sample. Associations between emotional disorders across genders in children of mothers with lifetime AN, and hyperactivity and peer difficulties in boys of mothers with lifetime BN confirm and extend previous findings and point to possible shared risk between ED and other psychopathology.

Predictive value of general movements' quality in low-risk infants for minor neurological dysfunction and behavioural problems at preschool age

BACKGROUND

General movement (GM) assessment is a well-established tool to predict cerebral palsy in high-risk infants. Little is known on the predictive value of GM assessment in low-risk populations.

AIMS

To assess the predictive value of GM quality in early infancy for the development of the clinically relevant form of minor neurological dysfunction (complex MND) and behavioral problems at preschool age.

STUDY DESIGN

Prospective cohort study.

SUBJECTS

A total of 216 members of the prospective Groningen Assisted Reproductive Techniques (ART) cohort study were included in this study. ART did not affect neurodevelopmental outcome of these relatively low-risk infants born to subfertile parents.

OUTCOME MEASURES

GM quality was determined at 2 weeks and 3 months. At 18 months and 4 years, the Hempel neurological examination was used to assess MND. At 4 years, parents completed the Child Behavior Checklist; this resulted in the total problem score (TPS), internalizing problem score (IPS), and externalizing problem score (EPS). Predictive values of definitely (DA) and mildly (MA) abnormal GMs were calculated.

RESULTS

DA GMs at 2 weeks were associated with complex MND at 18 months and atypical TPS and IPS at 4 years (all p<0.05). Sensitivity and positive predictive value of DA GMs at 2 weeks were rather low (13%-60%); specificity and negative predictive value were excellent (92%-99%). DA GMs at 3 months occurred too infrequently to calculate prediction. MA GMs were not associated with outcome.

CONCLUSIONS

GM quality as a single predictor for complex MND and behavioral problems at preschool age has limited clinical value in children at low risk for developmental disorders.

Congenital anomalies in offspring of subfertile couples: a registry-based study in the northern Netherlands

OBJECTIVE

To study whether specific congenital anomalies occur more often with a history of subfertility and/or the use of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

DESIGN

Case-only analyses.

SETTING

Not applicable.

PATIENT(S)

We included live births, stillbirths, and terminated pregnancies with congenital anomalies without a known cause that had a birth year between 1997 and 2010 (n = 4,525). A total of 4,185 malformed cases were born to fertile couples and 340 to subfertile couples, of whom 139 had conceived after IVF/ICSI and 201 had conceived naturally after >12 months.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The contribution, expressed in odds ratios (ORs), of a history of subfertility and IVF/ICSI to each specific type of congenital anomaly, imprinting disorder, and syndromal disorder.

RESULT(S)

We found subfertility to be associated with an increase in abdominal wall defects (adjusted OR [aOR] 2.43, 95% CI 1.05-5.62), penoscrotal hypospadia (aOR 9.83, 95% CI 3.58-27.04), right ventricular outflow tract obstruction (aOR 1.77, 95% CI 1.06-2.97), and methylation defects causing imprinting disorders (aOR 13.49, 95% CI 2.93-62.06). In vitro fertilization/ICSI was associated with an increased risk of polydactyly (OR 4.83, 95% CI 1.39-16.77) and more specifically polydactyly of the hands (OR 5.02, 95% CI 1.43-17.65).

CONCLUSION(S)

In our registry-based study, parental subfertility was associated with an increase in abdominal wall defects, penoscrotal hypospadia, right ventricular outflow tract obstruction, and methylation defects causing imprinting disorders. In vitro fertilization/ICSI was associated with an increase in polydactyly, mainly of the hands.

Developmental milestones in children born post-term in the Danish National Birth Cohort: a main research article

OBJECTIVE

To examine the timing of reaching developmental milestones in children born post-term.

DESIGN

Cohort study.

SETTING

The Danish National Birth Cohort: children born between 1997 and 2003.

POPULATION

Data were obtained from a cohort of 92 892 pregnancies participating in the first pregnancy interview. All singletons born in gestational weeks 39-45 were identified. The study was then restricted to children who participated in an interview at the age of approximately 18 months and had information on at least one developmental milestone. We excluded children of mothers with chronic diseases from the final analysis. The remaining study population constituted of 43 915 singletons (27 503 born at term; 16 412 born post-term).

METHODS

Logistic regression was used to calculate odds ratios of late achievement of these developmental milestones, adjusted for potential confounding factors.

MAIN OUTCOME MEASURES

Achieving developmental milestones at the time of interview or at a certain age.

RESULTS

More children born post-term achieved the assessed developmental milestones compared with children born at term (39-40 weeks). A test for trend for gestational ages 39, 40, and 41 weeks also showed a positive trend at achieving developmental milestones with gestational age at birth in nine out of 14 milestone items.

CONCLUSIONS

Children born post-term appear to reach the main developmental milestones at an earlier age than children born at term. The association could also result from bias related to a longer time between conception and interviewing, misclassification of end points, or selection bias.

Epigenetic status in the offspring of spontaneous and assisted conception

STUDY QUESTION

Is DNA methylation in buccal cell DNA from children born following IVF (in vitro fertilization) and ICSI (intra-cytoplasmic sperm injection) different from that of spontaneously conceived children?

SUMMARY ANSWER

DNA methylation in the imprinted gene, small nuclear ribonucleoprotein polypeptide N (SNRPN), was higher in children conceived by ICSI and in those born to women with the longest duration of infertility regardless of the method of conception.

WHAT IS KNOWN ALREADY

Fertility treatment is associated with a small but significant increase in the risk of a range of adverse obstetric outcomes, birth defects and longer term sequelae, but the biological basis for this is unknown. A growing evidence base suggests that epigenetics may play a role in subfertility and the link between fertility and health.

STUDY DESIGN, SIZE, DURATION

In this retrospective cohort study of children born between 2002 and 2008, we measured DNA methylation in paternally expressed gene 3 (PEG3), insulin-like growth factor II (IGF2), SNRPN, long interspersed nuclear element 1 (LINE1) and the insulin gene (INS) in buccal cell DNA from children born following IVF (n = 49) and ICSI (n = 20) and compared them with a matched spontaneous conception group (n = 86).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were identified from the Aberdeen Maternity and Neonatal Databank and IVF and ICSI pregnancies were matched to spontaneous conception pregnancies on year of birth and maternal age at delivery. Only singleton pregnancies following fresh embryo transfer were included. DNA methylation was determined by pyrosequencing. Regression with adjustment for covariates was used to determine the effect of infertility on offspring DNA methylation.

MAIN RESULTS AND THE ROLE OF CHANCE

SNRPN methylation in the offspring was linked to fertility treatment in the parents. This effect was specific to children conceived using ICSI and was apparent in the comparison of ICSI versus spontaneous conception (1.03%; 95% CI 0.10, 1.97; P = 0.031), ICSI versus standard IVF (1.13%; 95% CI 0.04, 2.23; P = 0.043) and ICSI versus standard IVF and spontaneous conception (1.05; 95% CI 0.15, 1.94; P = 0.023). In all comparisons, the use of ICSI was associated with a higher level of SNRPN methylation in the offspring. A higher level of SNRPN methylation in the offspring was also associated with a longer duration of infertility in the parents. This was observed in all cases of infertility (0.18% per year of infertility; 95% CI 0.02, 0.33; P = 0.026) and after excluding ICSI cases (0.21% per year of infertility; 95% CI 0.04, 0.37; P = 0.017). There was a significant increase in the level of LINE1 methylation with age between birth and 7 years (0.77% per year; 95% CI 0.49, 1.05; P < 0.001). Methylation in the INS gene decreased significantly over the same period (-0.46% per year; 95% CI -0.89, -0.03; P = 0.035). There was no evidence from this cross-sectional data that methylation within the imprinted genes changed over the first 7 years of life.

LIMITATIONS, REASONS FOR CAUTION

The ICSI sample size was limited but the groups were carefully selected and well matched and the SNRPN findings were consistent across different outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this study provide support for a role for epigenetics, and imprinting in particular, in fertility. The specific changes point to possible long-term consequences of fertility treatment for the health and fertility of future generations.

STUDY FUNDING/COMPETING INTEREST(S)

The authors report no conflict of interest in relation to this work. Funding was provided by the University of Aberdeen and the Scottish Government.

TRIAL REGISTRATION NUMBER

Not applicable.

Psychosocial job strain and risk of congenital malformations in offspring--a Danish National cohort study

OBJECTIVE

To investigate if maternal exposure to psychosocial job strain at work (high demands and low control) measured by questionnaire early in pregnancy (median week 15) is associated with malformations in the offspring.

DESIGN

Population-based cohort study.

SETTING

The Danish National Birth Cohort.

POPULATION

A cohort of 60,386 singleton children with full information on mother's occupational status, exposure to psychosocial job strain and all covariates during pregnancy.

METHODS

Logistic regression analysis was used to calculate the odds of congenital malformations as a function of job strain with adjustment for maternal age, body mass index, parity, smoking, alcohol use, manual versus nonmanual work, maternal serious disease and gestational age at interview.

MAIN OUTCOME MEASURES

Circulatory malformation, musculoskeletal malformation or any malformation.

RESULTS

Logistic regression analyses, both crude and adjusted, indicated no associations between working under high strain and giving birth to a child with circulatory malformation (adjusted odds ratio [OR] 1.04, 95% confidence interval [95% CI] 0.75-1.44), musculoskeletal malformation (aOR 0.88, 95% CI 0.71-1.10) or any malformation (aOR 0.99, 95% CI 0.85-1.15). Supplementary analyses including restriction to first-borns and a stratified analysis with respect to manual and nonmanual work did not change the results.

CONCLUSIONS

Association between exposure to high job strain during pregnancy and elevated risk of circulatory, muscle and any malformations is not supported by this study.

Increased time to pregnancy is associated with suboptimal neurological condition of 2-year-olds

OBJECTIVE

To evaluate whether time to pregnancy (TTP) is associated with neurological condition of 2-year-old children born to subfertile parents.

DESIGN

Data collected in a prospective, assessor-blinded follow-up study were used for cross-sectional analyses.

PATIENTS

Participants were the singletons of the Groningen assisted reproductive technique cohort study: all children were born to subfertile couples (n=209). The active waiting TTP of the couples obtained from fertility charts was recorded in years and months, and was converted to decimal years.

MAIN OUTCOME MEASURE

The presence of minor neurological dysfunction (MND), assessed with the Hempel examination.

RESULTS

MND was present in 16 (7.7%) children. TTP of children with MND (median 4.1, range 1.6-13.2) was significantly longer than that of children without MND (median 2.8, range 0.1-13.3; Mann-Whitney U test p=0.014). Logistic regression analysis on the contribution of TTP to MND resulted in a crude OR of 1.27 (95% CI 1.06 to 1.54). After correction for gestational age, parental age and parental level of education, the association remained statistically significant: OR=1.30 (95% CI 1.05 to 1.61).

CONCLUSIONS

Increased TTP was associated with suboptimal neurological development in 2-year-old children. This suggests that subfertility and its determinants are involved in the genesis of neurodevelopmental problems.

Movement variation in infants born following IVF/ICSI with and without ovarian hyperstimulation

BACKGROUND

The effect of in vitro fertilisation (IVF) on neurodevelopment is not fully understood. Probably, IVF does not affect traditional measures of neurodevelopment in infancy. Recently, an instrument, the Infant Motor Profile (IMP), was developed that evaluates the quality of motor behaviour. It includes the evaluation of movement variation (i.e. movement repertoire size), a parameter reflecting the integrity of cortical connectivity.

AIM

To evaluate the effect of ovarian hyperstimulation and the in vitro procedure on movement variation during infancy.

STUDY DESIGN

Prospective cohort study.

SUBJECTS

Singletons born following IVF or intracytoplasmic sperm injection (ICSI) with conventional controlled ovarian hyperstimulation (COH-IVF/ICSI, n=68), in a modified natural cycle (MNC-IVF/ICSI, n=57) and natural conception born to subfertile couples (Sub-NC, n=90).

OUTCOME MEASURES

Children were assessed with the IMP at 4, 10 and 18 months, resulting in a total IMP score and five domain scores: variation, variability, symmetry, fluency and performance. Primary outcome was the domain score variation.

RESULTS

A significant effect of study group was observed for the variation score up until 18 months of age (p=0.039). COH-IVF/ICSI children had a significantly lower mean variation score than MNC-IVF/ICSI children (mean difference [95% confidence interval] -1.010 [-1.766; -0.254]). Mean variation scores of COH-IVF/ICSI and Sub-NC children were similar; the same held true for the comparison between MNC-IVF/ICSI and Sub-NC. Total IMP scores and other domain scores of the three groups were similar.

CONCLUSION

The present study did not demonstrate a clear effect of ovarian hyperstimulation and the in vitro procedure on movement variation throughout infancy.

Assisted reproduction and child neurodevelopmental outcomes: a systematic review

OBJECTIVE

To systematically review the existing literature on neurodevelopmental outcomes in children born after medically assisted reproduction compared with those of children born after spontaneous conception.

DESIGN

Systematic review.

SETTING

Not applicable.

PATIENT(S)

Children born after medically assisted reproduction vs. reference groups of spontaneously conceived children.

INTERVENTION(S)

Data were reviewed from worldwide published articles, without restrictions as to publication year or language. A total of 80 studies included between 31 and 2,446,044 children.

MAIN OUTCOME MEASURE(S)

Child neurodevelopmental outcomes categorized as cognitive, behavioral, emotional or psychomotor development, or diagnoses of mental disorders.

RESULT(S)

For infants, studies on psychomotor development showed no deficits, but few investigated cognitive or behavioral development. Studies on toddlers generally reported normal cognitive, behavioral, socio-emotional, and psychomotor development. For children in middle childhood, development seems comparable in children born after assisted reproduction and controls, although fewer studies have been conducted with follow-up to this age. Very few studies have assessed neurodevelopmental outcomes among teens, and the results are inconclusive. Studies investigating the risk of diagnoses of mental disorders are generally large, with long follow-up, but the results are inconsistent.

CONCLUSION(S)

It may tentatively be concluded that the neurodevelopment of children born after fertility treatment is overall comparable to that in children born after spontaneous conception.

Assisted reproductive technologies and children's neurodevelopmental outcomes

Initial reports suggested that children conceived with assisted reproductive technologies (ART) may be at increased risk for a spectrum of developmental disabilities. Evolving evidence suggests that some of the early risks may have been overstated when not taking plurality of birth or gestational age at delivery into consideration, as both are independent risk factors for neurodevelopmental disabilities arising from alterations in structure and function or limitations in activities. Continued research is needed to overcome lingering data gaps in light of the equivocal literature for many neurodevelopmental disabilities relative to ART, increasing utilization of services, and changes in the clinical management of infecund couples such as the adoption of natural cycles or in vitro maturation treatment options. Population-based cohorts with longitudinal assessment of the multifaceted nature of neurodevelopment across critical and sensitive windows is paramount for the development of empirically based guidance for clinical and population health.

Low birth weight: is it related to assisted reproductive technology or underlying infertility?

Since 1978, we have witnessed a successful evolution of assisted reproductive technology (ART), with improvement of the pregnancy rates and a growing demand. However, in recent years, there has been increasing concern regarding its safety due to the potential health impact on its infants. The raise of the developmental origins of adult disease has positioned low birth weight (LBW) as a significant health issue. Although multiple studies have associated ART with LBW, the etiology of this association remains largely unknown. We review the potential association between different components of ART and infertility with LBW, while acknowledging the limitations of interpretation of the existing literature.

The longer-term health outcomes for children born as a result of IVF treatment. Part II--Mental health and development outcomes

BACKGROUND Limited data exist with regard to longer-term mental health and psychological functioning of children born from IVF treatment. With the known adverse perinatal outcome for children born from IVF treatment, it would be expected that there is a negative impact upon their mental development. METHODS A search strategy restricted to studies relating to the medical condition of children of at least 1 year of age, born from IVF treatment was performed to include case series, data linkage and prospective studies published from 1 January 2000 to 1 April 2012. RESULTS Limited long-term follow-up data suggest that there is an increase in the incidence of cerebral palsy and neurodevelopmental delay related to the confounders of prematurity and low birthweight. Previous reports of associations with autism and attention-deficit disorder are believed to be related to maternal and obstetric factors. There exists a potential increase in the prevalence of early adulthood clinical depression and binge drinking in the offspring of IVF, with the reassuring data of no changes with respect to cognitive development, school performance, social functioning and behaviour. Whether these potential associations are related to the IVF treatment, the adverse obstetric outcomes associated with IVF treatment, the genetic or subsequent environmental influences on the children is yet to be determined. CONCLUSIONS In general, the longer-term mental and emotional health outcome for children born from IVF treatment is reassuring, and is very similar to that of naturally conceived children; however, further studies are required to explore any association with depression, and its causality in more detail.

Prelinguistic behavior of infants of assisted reproductive techniques

OBJECTIVE

The aim of this study is assessment of effects of different assisted reproductive techniques (ART) like in vitro fertilization (IVF) and intra cytoplasmic sperm injection (ICSI) on prelinguistic behavior of infants conceived by these techniques.

METHODS

In this descriptive, cross sectional study, prelinguistic behavior of 151 full term ART infants of Royan Institute have been assessed in Children's Health and Development Research Center of Tehran from August 2007 until August 2009. Questionnaires were completed by parents at 9 months old. The questionnaire was standard according to Early Language Milestone Scale-2 (ELM-2). Data were analyzed by SPSS version 16 and using chi-square test.

FINDINGS

Twenty-two (14.5%) of infants were conceived by IVF and 129 (85.4%) by ICSI. Number of infants with delay in reduplicated babbling in ICSI method was more than in IVF. There was only a significant difference in echolalia delay in the two sexes. Echolalia was delayed more in boys. Delay of reduplicated babbling was more in infants of younger mothers. There was no relation between speech and language defect of parents and infants.

CONCLUSION

This study showed that prelingustic behavior of ART infants are affected by kind of ART method, infant sex, and mother's age at the time of pregnancy.

Why do singletons conceived after assisted reproduction technology have adverse perinatal outcome? Systematic review and meta-analysis

BACKGROUND

Assisted reproduction technology (ART) is used worldwide, at increasing rates, and data show that some adverse outcomes occur more frequently than following spontaneous conception (SC). Possible explanatory factors for the well-known adverse perinatal outcome in ART singletons were evaluated.

METHODS

PubMed and Cochrane databases from 1982 to 2012 were searched. Studies using donor or frozen oocytes were excluded, as well as those with no control group or including <100 children. The main outcome measure was preterm birth (PTB defined as delivery <37 weeks of gestation), and a random effects model was used for meta-analyses of PTB. Other outcomes were very PTB, low-birthweight (LBW), very LBW, small for gestational age and perinatal mortality.

RESULTS

The search returned 1255 articles and 65 of these met the inclusion criteria. The following were identified as predictors for PTB in singletons: SC in couples with time to pregnancy (TTP) > 1 year versus SC singletons in couples with TTP ≤ 1 year [adjusted odds ratio (AOR) 1.35, 95% confidence interval (CI) 1.22, 1.50]; IVF/ICSI versus SC singletons from subfertile couples (TTP > 1 year; AOR 1.55, 95% CI 1.30, 1.85); conception after ovulation induction and/or intrauterine insemination versus SC singletons where TTP ≤ 1 year (AOR 1.45, 95% CI 1.21, 1.74); IVF/ICSI singletons versus their non-ART singleton siblings (AOR 1.27, 95% CI 1.08, 1.49). The risk of PTB in singletons with a 'vanishing co-twin' versus from a single gestation was AOR of 1.73 (95% CI 1.54, 1.94) in the narrative data. ICSI versus IVF (AOR 0.80, 95% CI 0.69-0.93), and frozen embryo transfer versus fresh embryo transfer (AOR 0.85, 95% CI 0.76, 0.94) were associated with a lower risk of PTB.

CONCLUSIONS

Subfertility is a major risk factor for adverse perinatal outcome in ART singletons, however, even in the same mother an ART singleton has a poorer outcome than the non-ART sibling; hence, factors related to the hormone stimulation and/or IVF methods per se also may play a part. Further research is required into mechanisms of epigenetic modification in human embryos and the effects of cryopreservation on this, whether milder ovarian stimulation regimens can improve embryo quality and endometrial conditions, and whether longer culture times for embryos has a negative influence on the perinatal outcome.

Age of achievement of gross motor milestones in infancy and adiposity at age 3 years

Early life physical activity may help prevent obesity but is difficult to measure. The purpose of this study was to examine associations of age of achievement of gross motor milestones in infancy with adiposity at age 3 years. Seven forty one mother/infant dyads participated in a longitudinal study in Massachusetts. Exposures were age of attainment of 4 gross motor milestones-rolling over, sitting up, crawling, and walking. Outcomes were 3-year sum of subscapular and triceps skinfold thickness (SS + TR) for overall adiposity, their ratio (SS:TR) for central adiposity, and body mass index (BMI) z-score. We used linear regression models adjusted for confounders to examine motor milestone achievement and later adiposity. Rolling over (0.04, 95% CI: 0.008, 0.07) and sitting up (0.02, 95% CI: 0.001, 0.05) at ≥ 6 months were associated with increased SS:TR compared with attainment before 6 months. Walking at ≥ 15 months was associated with 0.98 mm higher SS + TR (95% CI: 0.05, 1.91) compared with walking before 12 months. Age at crawling was not associated with the outcomes. None of the milestones were associated with BMI z-score. Age of motor milestone achievement was only a modest predictor of adiposity. Later rolling over and sitting up were associated with greater central adiposity, and later age at walking was associated with greater overall adiposity at age 3 years. Although we controlled for birth weight and 6-month weight-for-length in our models, more detailed assessment of early adiposity prior to achievement of motor milestones is needed to help determine causality.

Assessing pre-implantation embryo development in mice provides a rationale for understanding potential adverse effects of ART and PGD procedures

Although the molecular events controlling human pre-implantation development remain unclear, mechanisms have been identified by analyzing these stages in mice. Through this approach, considerable insight has been gained into the events that operate to determine the first two cell fate decisions, occurring from zygote formation to the blastocyst prior to implantation. These mechanisms are related to cell polarization, cell division, cell-cell contact, and cell spatial position. Two developmental stages are essential for these processes to proceed adequately. Firstly, the second polar body must anchor to the external membrane during the first mitotic divisions of the embryo as its position is strongly biased to determine the plane of polarity. This in turn has important influence on the fate of the early blastomeres. Secondly, in the transition from the 8- to 16-cell stage, the cells that will form the inner cell mass are determined. Moreover, analyses performed on human oocytes and embryos have identified similar processes to those reported in mice and thus are evolutionarily conserved. Therefore, the understanding of mice pre-implantation embryo development provides a rationale to interpret current results of potential long-term adverse outcomes of Assisted Reproductive Technologies and Pre-implantation Genetic Diagnosis (PGD).

Comparison of the pregnancy outcomes of subfertile women after infertility treatment and in naturally conceived pregnancies

BACKGROUND

Adverse obstetric outcomes in pregnancies achieved through assisted reproductive technology (ART) could either be due to the technology or to the underlying subfertility or to both. To address this issue, we compared the pregnancy outcomes of singletons conceived naturally after a long time to pregnancy (TTP) with those of ART pregnancies.

METHODS

We analysed an existing birth database. Altogether 428 ART pregnancies were compared with 928 spontaneously conceived pregnancies with TTP of 2 years or more, during the period 1989-2007 at Kuopio University Hospital, Finland. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for pregnancy outcomes.

RESULTS

Between treated and untreated subfertile women no significant differences were found in the rates of Caesarean sections (OR 1.21, 95% CI 0.89-1.64), preterm births (OR 1.28, 95% CI 0.81-2.03), small for gestational age (SGA) birthweight (OR 0.95, 95% CI 0.65-1.39), need of neonatal intensive care (OR 1.28, 95% CI 0.88-1.88) or low Apgar scores (OR 1.19, 95% CI 0.47-3.04). However, compared with pregnancies of women with TTP 0-6 months, ART pregnancies had significantly increased risks of preterm or very preterm birth, low birthweight and need of neonatal intensive care.

CONCLUSIONS

The risks of preterm birth, SGA, need for neonatal intensive care and low Apgar scores were not significantly different between subfertile women who conceived spontaneously and those who conceived through ART indicating that maternal factors relating to subfertility and not only infertility treatment are associated with adverse pregnancy outcomes.

Effect of pregnancy planning and fertility treatment on cognitive outcomes in children at ages 3 and 5: longitudinal cohort study

OBJECTIVE

To investigate how pregnancy planning, time to conception, and infertility treatment influence cognitive development at ages 3 and 5.

DESIGN

Prospective population based cohort study.

SETTING

Millennium Cohort Study in the United Kingdom.

PARTICIPANTS

18,818 children recruited at 9 months and followed up at 3 and 5 years. 11,790 singletons with available data on pregnancy, cognitive outcomes, and confounders were included in analyses at age 3 and 12,136 at age 5. Exposure measures Mothers reported whether the pregnancy was planned, and their feelings when first pregnant; those in whom the pregnancy was planned provided time to conception, and details of any assisted reproductive technologies. The population was divided into "unplanned" (unplanned and unhappy), "mistimed" (unplanned but happy), "planned" (planned, time to conception <12 months), "subfertile" (planned, time to conception ≥ 12 months), "induced ovulation" (received clomiphene citrate), and "assisted reproduction" (in vitro fertilisation or intracytoplasmic sperm injection). The "planned" group was the comparison group in all analyses.

OUTCOME MEASURES

Three components of the British Ability Scales (BAS II). Naming vocabulary assessed verbal ability at age 3; this test was repeated at age 5 with the picture similarities and pattern construction subscales, which measure non-verbal and spatial abilities.

RESULTS

In unadjusted analyses, the scores on all scales in children from unplanned pregnancies were significantly lower than in those from planned pregnancies-for example, the difference in mean verbal ability score at age 3 was -4.8 (95% confidence interval -6.0 to -3.7; P<0.05), equivalent to an average delay of four months. After adjustment for sociodemographic factors these differences were attenuated: -0.3 (-1.3 to 0.7), equivalent to no delay. Children born after assisted reproduction performed consistently better in verbal ability tests (3.8 (-0.2 to 7.9) at age 3 and 3.5 (0.2 to 6.8) at age 5), which suggests that on average these children are three to four months ahead; this difference did not completely disappear with adjustment for confounders. Children born after infertility treatment had lower mean scores in non-verbal tests (-1.2 (-4.1 to 1.6) after assisted reproduction and -1.5 (-3.5 to 0.4) after induced ovulation) and in spatial ability tests (-2.7 (-6.9 to 1.6) after assisted reproduction), though the differences were not significant.

CONCLUSIONS

Pregnancy planning, subfertility, or assisted reproduction do not adversely affect children's cognitive development at age 3 or 5. The differences observed in the unadjusted analyses are almost entirely explained by marked inequalities in socioeconomic circumstances between the groups.

Time-to-pregnancy and risk of schizophrenia

Schizophrenia has been linked to advanced paternal age, but the explanation is unknown. We questioned whether the incidence of schizophrenia would be related to male reproductive capacity, as reflected in the time taken to conceive. We measured the incidence of schizophrenia in relation to time to conception in a sub-group of 12,269 in the Jerusalem cohort whose mothers, interviewed post-partum, reported that the pregnancy had been intended. Compared with those conceived in less than 3 months, the unadjusted relative risks (RR) of schizophrenia associated with conception-waits of 3-5, 6-11 and 12+ months were 1.10 (95% confidence interval, 0.62-1.94), 1.41 (0.79-2.52) and 1.88 (1.05-3.37) with p for trend=0.035. This trend was attenuated somewhat by adjusting for paternal age, and was observed more strongly in offspring of fathers aged 30+ (p=.010). These findings suggest that factors associated with fecundability, either male or female, may contribute to the risk of schizophrenia.