Growth of children conceived by IVF and ICSI up to 12years of age

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.

The Long-Term Outcome of Children Conceived Through Assisted Reproductive Technology

Assisted reproductive technology (ART) led to the birth of 60,381 infants in 2020 in Japan. This number is set to increase as the future interest in ART is anticipated to rise. Couples receiving ART are monitoring the outcomes of these treatments to see whether any differences exist between babies conceived naturally and those conceived via ART. This study investigated the relationship between the long-term outcome of children born from ART with a focus on physical and psychomotor developments. A large volume of data concerning each relationship with ART was collected from various observational studies. Several findings indicate that, over time, the physical characteristics of babies born by ART, and those born naturally are comparable. However, some reports indicate that, until they reach school age, there may be a small difference in growth. ART and naturally conceived children do not vary in academic achievement or attention deficit hyperactivity disorder. Taken together, it is difficult to conclude with certainty that ART is the source of these differences since they may arise from the child's genetic factors or their environment.

Culture conditions in the IVF laboratory: state of the ART and possible new directions

In the last four decades, the assisted reproductive technology (ART) field has witnessed advances, resulting in improving pregnancy rates and diminishing complications, in particular reduced incidence of multiple births. These improvements are secondary to advanced knowledge on embryonic physiology and metabolism, resulting in the ability to design new and improved culture conditions. Indeed, the incubator represents only a surrogate of the oviduct and uterus, and the culture conditions are only imitating the physiological environment of the female reproductive tract. In vivo, the embryo travels through a dynamic and changing environment from the oviduct to the uterus, while in vitro, the embryo is cultured in a static fashion. Importantly, while culture media play a critical role in optimising embryo development, a large host of additional factors are equally important. Additional potential variables, including but not limited to pH, temperature, osmolality, gas concentrations and light exposure need to be carefully controlled to prevent stress and permit optimal implantation potential. This manuscript will provide an overview of how different current culture conditions may affect oocyte and embryo viability with particular focus on human literature.

Anthropometric measurements of term singletons at 6 years of age born from fresh and frozen embryo transfer: A multicenter prospective study in Japan

Purpose

The purpose of this study is to compare anthropometric measurements between term singletons conceived via fresh embryo transfer (FreET) and frozen embryo transfer (FET) and those born via natural conception (NC) or fertility treatments milder than assisted reproductive technology (non-ART) at 6 years of age.

Methods

A total of 8149 children were enrolled, and questionnaires about anthropometric measures (weight, height, BMI) were addressed to parents, when the children were 1.5, 3, and 6 years of age. A total of 3299 term singletons were enrolled at birth: 533, 476, 916, and 1374 in the NC, non-ART, FreET, and FET groups, respectively.

Results

A total of 1635 term singletons (290, 176, 467, and 702 in the NC, non-ART, FreET, and FET groups respectively) were enrolled until 6 years of age (follow-up rate, approximately 50%). When non-ART group was used as control, the FreET children were 1.0 cm taller than the non-ART children at 6 years of age, after adjusting for confounding factors. However, no differences were observed in the anthropometric data among the non-ART, ART, and NC children at 6 years of age.

Conclusion

At 6 years of age, term singletons were taller in the FreET group than in the non-ART group, after adjusting for confounders.

Alteration of Genomic Imprinting after Assisted Reproductive Technologies and Long-Term Health

Assisted reproductive technologies (ART) are the treatment of choice for some infertile couples and even though these procedures are generally considered safe, children conceived by ART have shown higher reported risks of some perinatal and postnatal complications such as low birth weight, preterm birth, and childhood cancer. In addition, the frequency of some congenital imprinting disorders, like Beckwith-Wiedemann Syndrome and Silver-Russell Syndrome, is higher than expected in the general population after ART. Experimental evidence from animal studies suggests that ART can induce stress in the embryo and influence gene expression and DNA methylation. Human epigenome studies have generally revealed an enrichment of alterations in imprinted regions in children conceived by ART, but no global methylation alterations. ART procedures occur simultaneously with the establishment and maintenance of imprinting during embryonic development, so this may underlie the apparent sensitivity of imprinted regions to ART. The impact in adulthood of imprinting alterations that occurred during early embryonic development is still unclear, but some experimental evidence in mice showed higher risk to obesity and cardiovascular disease after the restriction of some imprinted genes in early embryonic development. This supports the hypothesis that imprinting alterations in early development might induce epigenetic programming of metabolism and affect long-term health. Given the growing use of ART, it is important to determine the impact of ART in genomic imprinting and long-term health.

Long-term growth in offspring of infertile parents: A 20-year follow-up study

INTRODUCTION

Long-term growth has been poorly investigated in boys and girls born to parents receiving fertility treatment. This study aimed to investigate the growth of children born following fertility treatment up to adulthood hypothesizing comparable growth in children born to parents receiving fertility treatment or to subfertile parents conceiving spontaneously to that in children spontaneously conceived by fertile parents.

MATERIAL AND METHODS

In this historical long-term follow-up study the study population consisted of 4151 singletons born at term in the Aarhus Birth Cohort between 1990 and 1992. Parental lifestyle and sociodemographic characteristics together with multiple measurements of weight and height were collected up to 20 years of age (6.1% of children contributed with at least one measurement for height or weight at age 20 years). The main outcome was difference in z-score for height (m) and weight (kg) between children conceived spontaneously (reference) and children conceived following fertility treatment, children conceived spontaneously by subfertile parents, or unplanned. Results were adjusted for pre-pregnancy maternal and paternal body mass index, maternal educational level, smoking during pregnancy, maternal age, and parity.

RESULTS

Singletons conceived following fertility treatment (n = 164; 4.0%) or by subfertile parents (n = 271; 6.5%) had comparable magnitude of weight estimates to children conceived spontaneously (difference in z-score per year 0.0148 [95% CI 0.0026-0.0270] and 0.0069 [95% CI -0.0028 to 0.0165], respectively). Height estimates were also comparable between groups of children conceived following fertility treatment or by subfertile parents (difference in z-score per year 0.0022 [95% CI -0.0075 to 0.0119]) compared with children conceived spontaneously (difference in z-score per year -0.0026 (95% CI -0.0103 to 0.0052). From the beginning of adolescence, we found lower weight for children born to subfertile parents and to parents receiving fertility treatment compared with spontaneously conceived children.

CONCLUSIONS

The main finding was equal long-term growth for children born at term by parents who received fertility treatment or parents waiting more than 12 months to conceive compared with spontaneously conceived children.

Health and fertility of ICSI-conceived young men: study protocol

STUDY QUESTIONS

What are the long-term health and reproductive outcomes for young men conceived using ICSI whose fathers had spermatogenic failure (STF)? Are there epigenetic consequences of ICSI conception?

WHAT IS KNOWN ALREADY

Currently, little is known about the health of ICSI-conceived adults, and in particular the health and reproductive potential of ICSI-conceived men whose fathers had STF. Only one group to date has assessed semen parameters and reproductive hormones in ICSI-conceived men and suggested higher rates of impaired semen quality compared to spontaneously conceived (SC) peers. Metabolic parameters in this same cohort of men were mostly comparable. No study has yet evaluated other aspects of adult health.

STUDY DESIGN SIZE DURATION

This cohort study aims to evaluate the general health and development (aim 1), fertility and metabolic parameters (aim 2) and epigenetic signatures (aim 3) of ICSI-conceived sons whose fathers had STF (ICSI study group). There are three age-matched control groups: ICSI-conceived sons whose fathers had obstructive azoospermia (OAZ) and who will be recruited in this study, as well as IVF sons and SC sons, recruited from other studies. Of 1112 ICSI parents including fathers with STF and OAZ, 78% (n = 867) of mothers and 74% (n = 823) of fathers were traced and contacted. Recruitment of ICSI sons started in March 2017 and will finish in July 2020. Based on preliminary participation rates, we estimate the following sample size will be achieved for the ICSI study group: mothers n = 275, fathers n = 225, sons n = 115. Per aim, the sample sizes of OAZ-ICSI (estimated), IVF and SC controls are: Aim 1-OAZ-ICSI: 28 (maternal surveys)/12 (son surveys), IVF: 352 (maternal surveys)/244 (son surveys), SC: 428 (maternal surveys)/255 (son surveys); Aim 2-OAZ-ICSI: 12, IVF: 72 (metabolic data), SC: 391 (metabolic data)/365 (reproductive data); Aim 3-OAZ-ICSI: 12, IVF: 71, SC: 292.

PARTICIPANTS/MATERIALS SETTING METHODS

Eligible parents are those who underwent ICSI at one of two major infertility treatment centres in Victoria, Australia and gave birth to one or more males between January 1994 and January 2000. Eligible sons are those aged 18 years or older, whose fathers had STF or OAZ, and whose parents allow researchers to approach sons. IVF and SC controls are age-matched men derived from previous studies, some from the same source population. Participating ICSI parents and sons complete a questionnaire, the latter also undergoing a clinical assessment. Outcome measures include validated survey questions, physical examination (testicular volumes, BMI and resting blood pressure), reproductive hormones (testosterone, sex hormone-binding globulin, FSH, LH), serum metabolic parameters (fasting glucose, insulin, lipid profile, highly sensitive C-reactive protein) and semen analysis. For epigenetic and future genetic analyses, ICSI sons provide specimens of blood, saliva, sperm and seminal fluid while their parents provide a saliva sample. The primary outcomes of interest are the number of mother-reported hospitalisations of the son; son-reported quality of life; prevalence of moderate-severe oligozoospermia (sperm concentration <5 million/ml) and DNA methylation profile. For each outcome, differences between the ICSI study group and each control group will be investigated using multivariable linear and logistic regression for continuous and binary outcomes, respectively. Results will be presented as adjusted odds ratios and 95% CIs.

STUDY FUNDING/COMPETING INTERESTS

This study is 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. 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, 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 a shareholder of Monash IVF Group and S.R.C. reports personal fees from Besins Healthcare and non-financial support from Merck outside of the submitted work. The remaining authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

TRIAL REGISTRATION DATE

Not applicable.

DATE OF FIRST PATIENT’S ENROLMENT

Not applicable.

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 INTEREST(S)

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

Small head circumference at birth: an 8-year retrospective cohort study in China

OBJECTIVE

Head circumference is considered a reliable assessment of the volume of the underlying brain. We sought to identify risk factors (maternal factors or antenatal antecedents) for microcephaly and to assess the effects of microcephaly on neonatal outcomes.

DESIGN

Retrospective cohort study.

SETTING

Data for all births in 2009-2017 were obtained from the Guangzhou Maternal-Fetal Care Database.

PARTICIPANTS

All singleton liveborn infants between 33 and 42 weeks' gestation (n=45 663) were categorised using the Intergrowth-21st standard for microcephaly.

MAIN OUTCOME MEASURES

Prevalence of mild, absolute and relative microcephaly at birth. We estimated associations of (1) maternal characteristics including Cantonese origin, parity, exposure to teratogens, TORCH infections (ie, Toxoplasma gondii, rubella virus, cytomegalovirus, herpes simplex virus), in vitro fertilisation conception, pre-eclampsia and maternal congenital anomalies with risk of each category of microcephaly, and (2) microcephaly with risk of in-hospital mortality and severe morbidity.

RESULTS

A total of 2709 infants had a head circumference z-score >2 SD, resulting in an overall prevalence of microcephaly of 59.3 per 1000 infants, consisting of mild (54.1 per 1000), absolute (2.8 per 1000) and relative microcephaly (2.4 per 1000). In multiple logistic regression, absolute microcephaly was associated with in utero exposure to teratogens (OR 4.2, 95% CI 2.0 to 8.8) and TORCH agents (OR 3.2, 95% CI 1.1 to 9.5). Mild microcephaly was associated with Cantonese descent (OR) 1.5, 95% CI 1.3 to 1.7) and primiparity (OR 1.7, 95% CI 1.5 to 2.0). Absolute microcephaly was associated with a significantly higher odds of neonatal seizure (OR 8.7, 95% CI 1.1 to 69.1). Mild microcephaly was not associated with adverse neonatal outcomes overall.

CONCLUSIONS

Cantonese origin, exposure to teratogens, pre-eclampsia and TORCH infection may be risk factors for microcephaly. The high prevalence of relative microcephaly and associated poor outcomes suggests that high-risk women merit closer clinical management and follow-up to maximise fetal head development during pregnancy.

The growth of assisted reproductive treatment-conceived children from birth to 5 years: a national cohort study

BACKGROUND

Birth weight and early child growth are important predictors of long-term cardiometabolic disease risk, in line with the Developmental Origins of Health and Disease hypothesis. As human assisted reproductive technologies (ARTs) occur during the sensitive periconceptional window of development, it has recently become a matter of urgency to investigate risk in ART-conceived children.

METHODS

We have conducted the first large-scale, national cohort study of early growth in ART children from birth to school age, linking the register of ART, held by the UK's Human Fertilisation and Embryology Authority, to Scottish maternity and child health databases.

RESULTS

In this study of 5200 ART and 20,800 naturally conceived (NC) control children, linear regression analysis revealed the birthweight of babies born from fresh embryo transfer cycles is 93.7 g [95% CI (76.6, 110.6)g] less than NC controls, whereas babies born from frozen embryo transfer (FET) cycles are 57.5 g [95% CI (30.7, 86.5)g] heavier. Fresh ART babies grew faster from birth (by 7.2 g/week) but remained lighter (by 171 g), at 6-8 weeks, than NC babies and 133 g smaller than FET babies; FET and NC babies were similar. Length and occipital-frontal circumference followed the same pattern. By school entry (4-7 years), weight, length and BMI in boys and girls conceived by fresh ART and FET were similar to those in NC children.

CONCLUSIONS

ART babies born from fresh embryo transfer grow more slowly in utero and in the first few weeks of life, but then show postnatal catch up growth by school age, compared to NC and FET babies. As low birth weight and postnatal catch-up are independent risk factors for cardiometabolic disease over the life-course, we suggest that further studies in this area are now warranted.

Childhood growth of singletons conceived following in vitro fertilisation or intracytoplasmic sperm injection: a systematic review and meta-analysis

BACKGROUND

Assisted reproductive techniques are associated with an increased risk of adverse pregnancy outcomes, including low birthweight and intrauterine growth restriction. Yet, the long-term follow-up on the growth of these children is limited.

OBJECTIVE

To systematically review the literature on post-neonatal height and weight among children conceived following in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment, compared with that of children born after spontaneous conception.

SEARCH STRATEGY

A systematic computerised literature search using the online databases PubMed, Embase, and Scopus.

SELECTION CRITERIA

Cohort or case-control studies with an exposed group of singletons conceived following IVF or ICSI along with a control group of spontaneously conceived singletons.

DATA COLLECTION AND ANALYSIS

Studies were reviewed by at least two authors. Meta-analyses were conducted using Cochrane Review Manager. The quality of the studies was assessed with the Newcastle-Ottawa Scale.

MAIN RESULTS

Twenty studies were included, with 13 of these eligible for meta-analyses. The meta-analyses compared 3972 children born after IVF/ICSI with 11 012 spontaneously conceived children and revealed no statistically significant difference in child weight [mean difference (MD) in weight of -160 g; 95% confidence interval (95% CI) -360, 3]. When stratifying by age of child at follow-up, we found a significant lower weight in children aged 0-4 years conceived following IVF/ICSI treatment (MD -180 g; 95% CI -320, -4), but this was no longer significant in children from 5 years of age (MD -160 g; 95% CI -580, 260). The pooled analysis revealed no statistically significant difference in childhood height.

CONCLUSIONS

In vitro fertilisation/ICSI was not associated with long-term weight and height.

TWEETABLE ABSTRACT

Children born following IVF/ICSI do not have impaired long-term weight or height compared with spontaneously conceived children.

Intracytoplasmic sperm injection: state of the art in humans

Among infertile couples, 25% involve both male and female factors, while male factor alone accounts for another 25% due to oligo-, astheno-, teratozoospermia, a combination of the three, or even a complete absence of sperm cells in the ejaculate and can lead to a poor prognosis even with the help of assisted reproductive technology (ART). Intracytoplasmic sperm injection (ICSI) has been with us now for a quarter of a century and in spite of the controversy generated since its inception, it remains in the forefront of the techniques utilized in ART. The development of ICSI in 1992 has drastically decreased the impact of male factor, resulting in millions of pregnancies worldwide for couples who, without ICSI, would have had little chance of having their own biological child. This review focuses on the state of the art of ICSI regarding utility of bioassays that evaluate male factor infertility beyond the standard semen analysis and describes the current application and advances in regard to ICSI, particularly the genetic and epigenetic characteristics of spermatozoa and their impact on reproductive outcome.

In Vitro fertilization and adverse obstetric and perinatal outcomes

Most IVF-conceived children are healthy, but IVF has also been associated with adverse obstetric and perinatal outcomes as well as congenital anomalies. There is also literature suggesting an association between IVF and neurodevelopmental disorders as well as potentially long-term metabolic outcomes. The main driver for adverse outcomes is the higher risk of multiple gestations in IVF, but as the field moves toward single embryo transfer, the rate of multiple gestations is decreasing. Studies have shown that singleton IVF pregnancies still have a higher incidence of adverse outcomes compared to unassisted singleton pregnancies. Infertility itself may be an independent risk factor. Animal models suggest that epigenetic changes in genes involved in growth and development are altered in IVF during the hormonal stimulation and embryo culture. Further animal research and prospective human data are needed to elucidate the mechanisms by which IVF may contribute to adverse outcomes and to decrease risks.

The health outcomes of human offspring conceived by assisted reproductive technologies (ART)

Concerns have been raised about the health and development of children conceived by assisted reproductive technologies (ART) since 1978. Controversially, ART has been linked with adverse obstetric and perinatal outcomes, an increased risk of birth defects, cancers, and growth and development disorders. Emerging evidence suggests that ART treatment may also predispose individuals to an increased risk of chronic ageing related diseases such as obesity, type 2 diabetes and cardiovascular disease. This review will summarize the available evidence on the short-term and long-term health outcomes of ART singletons, as multiple pregnancies after multiple embryos transfer, are associated with low birth weight and preterm delivery, which can separately increase risk of adverse postnatal outcomes, and impact long-term health. We will also examine the potential factors that may contribute to these health risks, and discuss underlying mechanisms, including epigenetic changes that may occur during the preimplantation period and reprogram development in utero, and adult health, later in life. Lastly, this review will consider the future directions with the view to optimize the long-term health of ART children.

Health and functioning of adolescents conceived by assisted reproductive technology

OBJECTIVE

To evaluate the general health, mental health, and cognitive ability of assisted reproductive technology (ART)-conceived adolescents.

DESIGN

A nested case-control study within a historic cohort.

SETTING

Not applicable.

PATIENT(S)

A total of 253 ART-conceived adolescents born between 1982 and 1993 and 253 matched references according to birth year, gender, and the high-school they attended.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Medical and psychiatric diagnoses, and cognitive ability recorded at the military preinduction screening (ages 16-17 years) and doctor's appointments throughout the military service.

RESULT(S)

No differences were detected in general and mental health of ART adolescents or cognitive ability, compared with the reference group. Similar results were obtained after stratification for gender and singleton births. The ART adolescents had fewer cases of discharge from military service due to health reasons (4% vs. 8.3%). Follow-up during the military service revealed that male ART adolescents had significantly more doctor's appointments compared with the reference group (23.80 ± 15.59 vs. 19.95 ± 13.79).

CONCLUSION(S)

Our preliminary results provide reassurance that in the long-run health and functioning of ART-conceived adolescents is not compromised. Further studies with larger cohorts are needed to confirm these results.

Infertility treatment and children's longitudinal growth between birth and 3 years of age

STUDY QUESTION

Does early childhood growth from birth through to 3 years of age differ by mode of conception?

SUMMARY ANSWER

Findings suggest early childhood growth was comparable for children irrespective of infertility treatment, but twins conceived with ovulation induction with or without intrauterine insemination (OI/IUI) were slightly smaller than twins conceived without treatment.

WHAT IS KNOWN ALREADY

Although studies have found that babies conceived with infertility treatment are born lighter and earlier than infants conceived without treatment, little research especially for non-assisted reproductive technology (ART) treatments has focused on their continued growth during early childhood.

STUDY DESIGN, SIZE, DURATION

Upstate KIDS recruited infants born (2008-2010) to resident upstate New York mothers. Infants were sampled based on birth certificate indication of infertility treatment; specifically, for every singleton conceived by infertility treatment, three singletons without infertility treatment were recruited and matched on region of birth. All multiple births irrespective of treatment were also recruited. Children were prospectively followed, returning questionnaires every 4-6 months until 3 years of age. In total, 3905 singletons, 1129 sets of multiples (96% of whom were twins) enrolled into the study. Analyses included 3440 (88%) singletons (969 conceived with treatment; specifically, 433 with ART and 535 with OI/IUI) and 991 (88%) sets of multiples (439 conceived with treatment; specifically 233 with ART and 206 with OI/IUI) with growth data available.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Mothers reported infertility treatment use at baseline and children's height and weight from pediatric visits. Self-reported use of ART was previously verified by linkage with the US Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) database. Mixed linear models with cubic splines accounting for age and age-gender interactions were used to estimate mean differences in growth from birth to 3 years by infertility treatment status and adjusting for maternal age, race, education, private insurance, smoking status during pregnancy, maternal pre-pregnancy and paternal body mass indices (BMI).

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with singletons conceived without treatment (n = 2471), singletons conceived by infertility treatment (433 by assisted reproductive technologies (ART), 535 by OI/IUI and 1 unknown specific type) did not differ in growth. Compared with twins not conceived with treatment (n = 1076), twins conceived with OI/IUI (n = 368) weighed slightly less over follow-up (122 g). They were also proportionally smaller for their length (-0.17 weight-for-length z-score units). No differences in mean size over the 3 years were observed for twins conceived by ART, though some evidence of rapid weight gain from birth to 4 months (adjusted OR 1.08; 95% CI: 1.00-1.16) suggestive of catch up growth was observed.

LIMITATIONS, REASONS FOR CAUTION

Participants from upstate New York may not be representative of US infants. Although accounted for in statistical analysis, attrition during follow-up may have limited power to detect small differences.

WIDER IMPLICATIONS OF THE FINDINGS

This study is the first to prospectively track the growth of children conceived with and without infertility treatment in the USA, including a substantial number of twins. Our findings are similar to what was previously observed in the ART literature outside of the states.

STUDY FUNDING/COMPETING INTERESTS

Supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD; contracts #HHSN275201200005C, #HHSN267200700019C). Authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

The paternal genome and the health of the assisted reproductive technology child

As a number of children born by assisted reproductive technology (ART) are increasing each year across the developed world, the health of such offspring is a matter of public concern. Does the integrity of the paternal genome impact on offspring health? In societal terms, as birth rates fall, and the Western population become unsustainable, do the benefits outweigh the costs of creating and providing for this ART conceived subpopulation? There are little data to date to answer these questions. The long-term health of such children has largely been ignored, and success measured only by early (prebirth) outcomes such as embryo quality or pregnancy. However, there are powerful paradigms such as ageing and smoking that give vital clues as to the potential impact of unhealthy spermatozoa on disease risk, mental and physical health, fertility and mortality of these offspring.

IVF culture media: past, present and future

BACKGROUND

The advances in the world of IVF during the last decades have been rapid and impressive and culture media play a major role in this success. Until the 1980s fertility centers made their media in house. Nowadays, there are numerous commercially available culture media that contain various components including nutrients, vitamins and growth factors. This review goes through the past, present and future of IVF culture media and explores their composition and quality assessment.

METHODS

A computerized search was performed in PubMed regarding IVF culture media including results from 1929 until March 2014. Information was gathered from the websites of companies who market culture media, advertising material, instructions for use and certificates of analysis. The regulation regarding IVF media mainly in the European Union (EU) but also in non-European countries was explored.

RESULTS

The keyword 'IVF culture media' gave 923 results in PubMed and 'embryo culture media' 12 068 results dating from 1912 until March 2014, depicting the increased scientific activity in this field. The commercialization of IVF culture media has increased the standards bringing a great variety of options into clinical practice. However, it has led to reduced transparency and comparisons of brand names that do not facilitate the scientific dialogue. Furthermore, there is some evidence suggesting that suboptimal culture conditions could cause long-term reprogramming in the embryo as the periconception period is particularly susceptible to epigenetic alterations. IVF media are now classified as class III medical devices and only CE (Conformité Européene)-marked media should be used in the EU.

CONCLUSION

The CE marking of IVF culture media is a significant development in the field. However, the quality and efficiency of culture media should be monitored closely. Well-designed randomized controlled trials, large epidemiological studies and full transparency should be the next steps. Reliable, standardized models assessing multiple end-points and post-implantation development should replace the mouse embryo assay. Structured long-term follow-up of children conceived by assisted reproduction technologies and traceability are of paramount importance.

Safety of intracytoplasmic sperm injection

Early follow-up studies of IVF children showed that the frequency of birth anomalies resembled those arising with natural conception. More detailed analyses confirmed these findings, reinforcing the concept of the preimplantation period as teratologically "safe." The use of intracytoplasmic sperm injection (ICSI) to achieve fertilization introduced another variable.ICSI's safety has often been criticized because the fertilizing spermatozoon neither binds to the zona pellucida nor fuses with oolemma. Bypassing these physiologic steps together with the arbitrary selection of the spermatozoon has been reason for concern. Thus far, ICSI offspring undergoing adolescence and beyond has provided sufficient information to reassure these qualms. In fact, the health of the offspring generated through ICSI, once taken into consideration the gestational order, the age and the genetic makeup of the couples are generally reassuring.

Long-term follow-up of children conceived through assisted reproductive technology

Children conceived via assisted reproductive technologies (ART) are nowadays a substantial proportion of the population. It is important to follow up these children and evaluate whether they have elevated health risks compared to naturally conceived (NC) children. In recent years there has been a lot of work in this field. This review will summarize what is known about the health of ART-conceived children, encompassing neonatal outcomes, birth defects, growth and gonadal developments, physical health, neurological and neurodevelopmental outcomes, psychosocial developments, risk for cancer, and epigenetic abnormalities. Most of the children conceived after ART are normal. However, there is increasing evidence that ART-conceived children are at higher risk of poor perinatal outcome, birth defects, and epigenetic disorders, and the mechanism(s) leading to these changes have not been elucidated. Continuous follow-up of children after ART is of great importance as they progress through adolescence into adulthood, and new ART techniques are constantly being introduced.

Phenotypic differences in children conceived from fresh and thawed embryos in in vitro fertilization compared with naturally conceived children

OBJECTIVE

To determine whether anthropometric and biochemical features differ in in vitro fertilization (IVF) children conceived via fresh (IVFF) or thawed (IVFT) embryo transfer compared with naturally conceived controls.

DESIGN

A cross-sectional controlled study.

SETTING

University clinical research unit.

PATIENT(S)

Healthy prepubertal children (3.5-11.0 years), singletons, born at term (>37 weeks), who were either naturally conceived (controls; n = 94) or IVF children conceived via the transfer of a fresh (IVFF; n = 72) or thawed (IVFT; n = 43) embryo.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Assessments of anthropometry (adjusted for parental variables), dual-energy X-ray absorptiometry-derived body composition, fasting plasma growth factors, lipids, and parameters of glucose regulation.

RESULT(S)

The IVFF but not the IVFT children weighed less at birth than the control children. The IVFF children were taller than both the controls and IVFT children. Sex-specific analyses showed height differences among girls, with IVFF girls being taller than their control and IVFT counterparts. Taller stature in IVFF children was associated with increased insulin-like growth factor I (IGF-I) concentrations compared with controls, whereas the IVFT children displayed increased IGF-II and decreased insulin-like growth factor binding protein 3 (IGFBP-3) concentrations compared with the controls. More favorable lipid profiles were also evident in IVFF but not IVFT children compared with the control children.

CONCLUSION(S)

These preliminary findings highlight that the transfer of a fresh versus a thawed IVF embryo affects height, plasma growth factor, and lipid profiles in childhood. Therefore, embryo derivation should be considered when assessing physical and biochemical phenotype of IVF children.

The longer-term health outcomes for children born as a result of IVF treatment: Part I--General health outcomes

BACKGROUND Several million children have been born from in vitro fertilization (IVF) treatment, but limited data exist regarding their health and development beyond the first year of life. It has been alleged that IVF may lead to long-term adverse consequences, in addition to the documented worse perinatal outcome and increased risk of congenital abnormalities in children born resulting from IVF treatment. METHODS A search strategy restricted to studies relating to the medical condition of children of at least 1 year of age born as a result of IVF treatment was performed to include case series, data linkage and prospective studies published 1 January 2000-1 April 2012. RESULTS Limited long-term follow-up data suggest that there is potentially an increase in the incidence of raised blood pressure, elevated fasting glucose, increase in total body fat composition, advancement of bone age and potentially subclinical thyroid disorder in the IVF offspring. Whether these potential associations are related to the IVF treatment per se, the adverse obstetric outcomes associated with IVF treatment or are related to the genetic origin of the children is yet to be determined. CONCLUSIONS This review provides evidence to suggest that the short-term health outcome for children born from IVF treatment is positive. However, it is expected that the cardiovascular and metabolic risk factors found in childhood and tracking into adulthood could be worse in later life, and may be responsible for chronic cardiometabolic disease. These observations need to be addressed by further studies.

Is ICSI Risky?

As assisted reproductive technology (ART) methods become the mainstream of infertility treatment, it has become even more critical to reassess its safety. Following the results of a study published by the Robinson Institute in the New England Journal of Medicine, the risk of ART, especially intracytoplasmic sperm injection (ICSI), has never been so closely scrutinized. This paper traces the origins and development of ICSI, assesses the risks documented in the literature, and finally interprets the implications of the study for couples contemplating therapy. We support the need for continued vigilance towards ICSI and the importance in investigating male-factor infertility as a prequel to its use.

Comparison of Growth Parameters of 5-year-old Singleton Children Born in Assisted Versus Natural Conception

Introduction: At present, about 1% of newborns are delivered through assisted reproductive technologies (ART) worldwide. This study aimed to evaluate and compare the growth parameters of children born in assisted and natural conception at 5 years of age. Materials and Methods: In a cross-sectional case control study, weight, height and head circumference of 5-year old children were assessed. The case group consisted of term, singleton babies who were products of ART in the Center for Infertility of Shahid Sadoughi University, Yazd, Iran in 2005. The control group consisted of term, first child, singleton and spontaneously conceived 5-year-old children who were referred for vaccination to primary health care center of Shahid Akbari in 2010. Results: Fifty-eight girls (47.5%) and 64 boys (52.5%) “with equal numbers in each of the 2 groups” were evaluated. Sex distribution, mean ages of fathers and mothers were not statistically significant different in both groups. Children born after ART tend to have lower birth weight, smaller birth head circumference and lower weight at 5 years of age. Having low birth weight (<2500 g), being underweight and having short stature at the age of 5 were more common in babies born through ART. Conclusion: Growth retardation is more prevalent in babies born through ART. Thus, growth assessment, parents’ knowledge about child physical development, and timely and accurate follow-up of these children are necessary for early detection of any growth disorders. Key words: ART, Growth, Height, Natural Conception, Weight

Cardiometabolic health of children conceived by assisted reproductive technologies

The cardiometabolic health of children conceived by assisted reproductive technologies (ART) compared with children conceived without medical assistance is unclear. Although the majority of published studies evaluating height, weight, and body mass index have not found differences by method of conception, some studies have indicated differences in adiposity by more direct measures such as skinfolds and dual X-ray absorptiometry. Far fewer studies have investigated other cardiometabolic characteristics, such as blood pressure and measures of lipid and glucose metabolism. Of these studies, some indications of increased blood pressure and recent findings of vascular dysfunction among children conceived by ART compared with children conceived without ART warrant further investigation. Epigenetic differences may be the global mechanism at work, resulting from different aspects of ART treatment, such as ovarian stimulation, in vitro culture, and manipulation of sperm, among other considerations. Fetal growth and placental development may serve as mediators of these effects. Future studies should consider recruiting sufficient numbers of ART and non-ART conceived multiples and collect information on indicators of cardiometabolic health in the parents. Despite some advantages of sibling cohorts in developmental origins research, its feasibility and utility for investigating health of children conceived by ART remains debatable.

Maternal fecundity and asthma among offspring-is the risk programmed preconceptionally? Retrospective observational study

OBJECTIVE

To evaluate the association between maternal fecundity factors and time to pregnancy and risk of asthma in offspring.

DESIGN

Retrospective observational hospital-based birth cohort study.

SETTING

A university-based obstetrics and gynecology department.

PATIENT(S)

A total of 40,914 women, who delivered between 1989 and 2007, were linked with the register for asthma reimbursement (n = 2,577) for their offspring. Fecundity factors were recorded during pregnancy. Logistic regression analyses were used.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Asthma among offspring.

RESULT(S)

The risk of asthma was significantly increased if the mother had any infertility problems (adjusted odds ratio [adjusted OR] 1.39, 95% confidence interval [CI] 1.19-1.63), medical infertility treatment (aOR 1.43, 95% CI 1.13-1.80), or any infertility treatment (aOR 1.50, 95% CI 1.26-1.79). The risk of asthma among offspring was also higher among mothers who had more than two miscarriages (aOR 1.25, 95% CI 1.04-1.51) and time to pregnancy over 3 months (aOR 1.25, 95% CI 1.07-1.45).

CONCLUSION(S)

These findings suggest that maternal subfertility exposes offspring to an increased risk of asthma.

CLINICAL TRIAL REGISTRATION NUMBER

The study is registered in Kuopio University Hospital register (TUTKI): ID 5302448.

Development and current applications of assisted fertilization

Since the very early establishment of in vitro insemination, it became clear that one of the limiting steps is the achievement of fertilization. Among the different assisted fertilization methods, intracytoplasmic sperm injection emerged as the ultimate technique to allow fertilization with ejaculated, epididymal, and testicular spermatozoa. This work describes the early steps that brought forth the development of intracytoplasmic sperm injection and its role in assisted reproductive techniques. The current methods to select the preferential male gamete will be elucidated and the concerns related to the offspring of severe male factor couples will be discussed.

Outcomes for offspring of men having ICSI for male factor infertility

Since the introduction of intracytoplasmic sperm injection (ICSI) using single sperm isolated from testicular tissue in men with obstructive and non-obstructive azoospermia, or using ejaculated sperm in those with poor semen quality, there have been concerns that this might have adverse effects on the offspring compared to conventional in vitro fertilisation (IVF) and natural conceptions. ICSI is done for reasons other than male factor infertility, and on the whole has not been shown to have any more negative effects than those seen with IVF. There have however, been very few studies of ICSI with a focus on, or large enough numbers to examine, the specific outcomes associated with male factor infertility. From the limited information available in relation to the source of the sperm and aetiology of infertility in the presence of ICSI, there appears to be no increased risk of congenital malformations. There is, however, a small increase in both de novo and inherited chromosome abnormalities. In terms of growth and neurodevelopment, there are very few studies, and so far, no adverse outcomes have been found in young children whose fathers have a sperm defect. The origin of the sperm used in ICSI does not have a major influence on the early life outcomes for the offspring, but transgenerational and epigenetic effects remain unknown. When the male factor infertility is known or thought to be due to a Y-chromosome deletion, this information should be given to the young male offspring at a time that will ensure his own reproductive health and plans are optimized.

Are ICSI adolescents at risk for increased adiposity?

BACKGROUND

Puberty is a critical period for the development of cardio-metabolic disturbances, including a more central body fat distribution. It is still unclear if IVF and more specifically ICSI, can permanently and detrimentally affect body fat accumulation in the human offspring. Therefore, adiposity and body fat distribution in 14-year-old adolescents born after ICSI were investigated.

METHODS

Body composition data, including anthropometry (weight, height and BMI), skinfold thicknesses (peripheral: triceps and biceps skinfolds; central: supra-iliacal and subscapular skinfolds; total: sum of the four skinfolds) and circumferences (waist, mid-upper arm) were compared between 217 ICSI singletons (116 boys, 101 girls) and 223 singletons (115 boys, 108 girls) born after spontaneous conception (SC). ICSI teenagers were part of a previously published ICSI cohort followed since birth; SC controls were recruited from schools in the surroundings.

RESULTS

Among all boys, no differences in body composition measurements were found between the ICSI and SC group, taking into account confounding variables. In boys with more advanced pubertal stages, a significantly higher sum of peripheral skinfolds was found in the ICSI group compared with the SC group (difference 3.5 mm, 95% confidence interval 0.3-6.6). In girls, peripheral adiposity assessed by skinfolds and mid-upper arm circumference, and central adiposity assessed by skinfolds and waist circumference as well as total adiposity assessed by BMI, the sum of four skinfold thicknesses and skinfold-derived body fat percentage were significantly higher in the ICSI group compared with the SC group, taking into account confounding variables (all P< 0.05). Neither parental nor early life factors could explain the differences.

CONCLUSIONS

We found that pubertal ICSI girls were more prone to central, peripheral and total adiposity compared with their SC counterparts. ICSI adolescents with advanced pubertal stages showed more peripheral adiposity. Continued monitoring of body fat patterns in adolescents born after fertility treatment is mandatory in order to assess their risk for developing obesity and its related adverse health effects in adulthood.

Childhood outcomes of assisted reproductive technology

There is a large population of children conceived via assisted reproductive technology (ART), which continues to increase worldwide, without a clear understanding of associated long-term outcomes. ART children are more likely to be the result of multiple pregnancies, and thus to be born prematurely or low birthweight. There is growing evidence that ART children are phenotypically and biochemically different from naturally conceived children, but the mechanism(s) leading to these changes have not been elucidated. There is a possible increased risk of rare imprinted gene disorders in these children. However, it remains unclear whether more subtle changes in DNA methylation occur commonly, leading to differences in gene expression and phenotype in ART children. Although an increased risk of cancer among ART children has been reported, the role of ART in the development of cancer has not been demonstrated. Further research and ongoing surveillance of ART children is essential to better understand the possible effects of ART on the long-term health of this population.

Clinical management of male infertility in assisted reproduction: ICSI and beyond

The advent of in vitro fertilization and its augmentation with intracytoplasmic sperm injection (ICSI) has allowed a large number of couples suffering from moderate to severe male infertility, and also presenting with female pathologies, to achieve their reproductive dreams. Notwithstanding the existence of fundamental questions about the pathophysiological mechanisms leading to sperm dysfunction, and still unanswered concerns about health risks following ICSI, it appears that overall ICSI is safe and here to stay. Although on one hand ICSI possibly hampered advances of the knowledge in some areas of gamete biology and interaction, on the other it definitely gave impulse to studies designed to unveil the sperm contributions during and beyond fertilization, including the normalcy of the DNA/chromatin as well as molecular mechanisms of genetic/epigenetic control and nuclear organization status. In all, almost entering the fourth decade of assisted reproductive technologies, we should continue monitoring the safety of the technique and long-term development of offspring, whereas at the same time prioritizing areas of research addressing these fundamental questions.

[Procedure used to follow-up a cohort of IVF children. Interests and limits of tools performed to longitudinal follow up for a monocentric cohort]

BACKGROUND

Follow-up of in vitro fertilization (IVF) children is recommended by the French health authorities. Follow-up procedures were set-up in a medically assisted reproduction unit at the Saint-Joseph Hospital in Marseille. The objective was to ensure effective follow-up. In this context, it is important to determinate weather the designated tools are appropriate for evaluating the desired developmental outcomes. This study was designed to describe the surveillance tool and to demonstrate its usefulness and limitations.

METHODS

The procedure was initiated in 2004. All existing data for every livebirth child were collected, including data concerning all IVF attempts, medical reports of pregnancy, and child health records. Parents were asked to complete questionnaires and provide their child's personal health records since birth. The quality of the data was evaluated using prenatal and postnatal analysis. The longitudinal anthropometric data of the health records were used to describe the percentiles of weights and heights from birth to 6 years in this population at age-specific reference intervals.

RESULTS

The follow-up concerned 2081 children born since 1995 with a response rate of 68,9%. A brief descriptive analysis was performed for the cohort and for a group of 1053 children aged five years and older, 225 representative personal health records were used to estimate quintiles for anthropometric data.

CONCLUSION

The procedure adopted for the follow-up of in vitro fertilization children meets the established qualitative health requirements. This method provides many benefits with no risk for the children. Data collection from personal health records enabled an exploitation of growth data by including the calculation of anthropometric percentiles in this IVF population. This report presents the first set of IVF child growth standards used as health indicator and health trend measurement.