Right ventricular dysfunction in children and adolescents conceived by assisted reproductive technologies

Subclinical cardiac impairments in fetuses conceived through assisted reproductive technology by speckle tracking echocardiography

OBJECTIVES

To evaluate the changes of cardiac morphology and function in fetuses conceived through assisted reproductive technologies (ART) by speckle tracking echocardiography.

METHODS

A retrospective study was conducted in 101 spontaneously conceived (SC) fetuses and 99 ART-conceived ones. Fetal echocardiography was performed, fetal cardiac morphology and function were analyzed using two-dimensional speckle tracking software, including global sphericity index (GSI), global longitudinal strain (GLS), fractional area change (FAC) of the left and right ventricles, as well as segmental sphericity index (SI), end-diastolic diameter (ED), and fractional shortening (FS) in 24 segments.

RESULTS

Compared to the SC fetuses, the ART-conceived fetuses exhibited decreased GSI (median [interquartile range], 1.22 [1.16-1.27] vs. 1.18 [1.11-1.24], p=0.007), decreased right ventricular GLS (24.9 [21.5-27.6] vs. 23.2 [20.4-26.8], p=0.026), and decreased right ventricular FAC (mean ± standard deviation, 39.7 ± 6.4 vs. 37.2 ± 7.1, p=0.003). Analysis of the 24 segments showed that ART-conceived fetuses had reduced SI in the apical segments of right ventricle and increased ED in several segments of the right ventricle.

CONCLUSIONS

Fetuses conceived through ART had a more spherical shape of the global heart and predominantly right-sided cardiac remodeling and systolic function impairment.

The effect of fertility treatment and socioeconomic status on neonatal and post-neonatal mortality in the United States

OBJECTIVE

To determine the association between fertility treatment, socioeconomic status (SES), and neonatal and post-neonatal mortality.

STUDY DESIGN

Retrospective cohort study of all births (19,350,344) and infant deaths from 2014-2018 in the United States. The exposure was mode of conception-spontaneous vs fertility treatment. The outcome was neonatal (<28d), and post-neonatal (28d-1y) mortality. Multivariable logistic models were stratified by SES.

RESULT

The fertility treatment group had statistically significantly higher odds of neonatal mortality (high SES OR 1.59; CI [1.5, 1.68], low SES OR 2.11; CI [1.79, 2.48]) and lower odds of post-neonatal mortality (high SES OR 0.87, CI [0.76, 0.996], low SES OR 0.6, CI [0.38, 0.95]). SES significantly modified the effect of ART/NIFT on neonatal and post-neonatal mortality.

CONCLUSIONS

Fertility treatment is associated with higher neonatal and lower post-neonatal mortality and SES modifies this effect. Socioeconomic policies and support for vulnerable families may help reduce rates of infant mortality.

Cardiovascular health of offspring conceived by assisted reproduction technology: a comprehensive review

Recently, the use of assisted reproductive technology (ART) has rapidly increased. As a result, an increasing number of people are concerned about the safety of offspring produced through ART. Moreover, emerging evidence suggests an increased risk of cardiovascular disease (CVD) in offspring conceived using ART. In this review, we discuss the epigenetic mechanisms involved in altered DNA methylation, histone modification, and microRNA expression, as well as imprinting disorders. We also summarize studies on cardiovascular changes and other risk factors for cardiovascular disease, such as adverse intrauterine environments, perinatal complications, and altered metabolism following assisted reproductive technology (ART). Finally, we emphasize the epigenetic mechanisms underlying the increased risk of CVD in offspring conceived through ART, which could contribute to the early diagnosis and prevention of CVD in the ART population.

Investigating the Association of Assisted Reproduction Techniques and Adverse Perinatal Outcomes

BACKGROUND

Infertility affects about 80 million individuals worldwide and 10-15% of couples at reproductive age will seek medical assistance. There is increasing evidence that pregnancies after Assisted Reproduction Techniques (ART) are associated with pre-term birth, low birthweight, congenital defects, and increased mortality rates. The aim of this review is to assess all the published literature and provide an updated review on the effect of assisted conception and perinatal and neonatal outcomes.

METHODS

Comprehensive research on Pubmed/Medline, Scopus, and Google scholar electronic databases was conducted from July 2023 up to September 2023, using the terms assisted reproductive techniques, ART, in vitro fertilization, IVF, intracytoplasmic sperm injection, ICSI, preterm birth, PTB, low birth weight, LBW, chromosomal defects, congenital defects, and hypospadias. In total, 87 full text articles were retrieved and after a careful evaluation, 31 studies were selected for data extraction.

RESULTS

Our review demonstrated a higher risk of congenital and chromosomal defects, and a higher incidence of male genital tract defects and heart defects in ART pregnancies. Regarding pre-term birth, our results were contradictory.

CONCLUSIONS

Although assisted reproduction techniques are associated with increased risks, they are safe regarding perinatal outcomes and couples should not be discouraged from utilizing them. Our results aim to alert clinicians to these specific outcomes and offer more personalized care and counseling to infertile couples and their children.

Subfertility versus ART: unraveling the origins of fetal cardiac programming

STUDY QUESTION

Do spontaneously conceived (SC) fetuses from subfertile couples show the same signs of cardiac remodeling as those observed after IVF treatments?

SUMMARY ANSWER

As opposed to fetuses from IVF, SC fetuses from subfertile couples do not show cardiac remodeling and present a similar cardiac structure and function to those of SC fetuses from fertile couples.

WHAT IS KNOWN ALREADY

Subjects conceived by IVF present signs of cardiac remodeling and suboptimal function in utero and during childhood, including larger atria, more globular and thicker ventricles, reduced longitudinal motion, and impaired relaxation as compared to SC individuals from fertile couples. There are no previous publications investigating the independent cardiac programming effects of infertility in SC fetuses from subfertile couples (with time-to-pregnancy (TTP) over 12 months).

STUDY DESIGN, SIZE, DURATION

A prospective cohort study of 289 singleton pregnancies exposed and not exposed to subfertility recruited from 2019 to 2021, including 96 SC pregnancies from fertile couples (TTP under 12 months), 97 SC from subfertile couples (TTP over 12 months), and 96 from IVF after fresh embryo transfer. Fetal echocardiography was performed in all pregnancies. Epidemiological data and perinatal outcomes were collected in all pregnancies. The overall attrition rate was 15.7%.

PARTICIPANTS/MATERIALS, SETTING, METHODS

SC from subfertile couples and IVF pregnancies were identified as eligible at pregnancy diagnosis, and eligible SC pregnancies from fertile couples who attended our maternal-fetal unit were invited to participate at third trimester, being matched to the other groups by maternal age. Fetal echocardiography was performed at 29-34 weeks of pregnancy to assess cardiac structure and function, and results were adjusted by parental age, maternal smoking status, child's birth order, birthweight centile, gestational age, and estimated fetal weight at scan.

MAIN RESULTS AND THE ROLE OF CHANCE

Parental age, ethnicity, BMI, and smoking exposure, median gestational age and estimated fetal weight were similar in all study groups. There were no significant differences in infertility duration or etiology between the subfertile and the IVF populations (TTP: subfertile median 35 months (interquartile range 20-48) versus IVF: 47 (25-61); P-value = 0.051). While both fertile and subfertile SC groups presented similar fetal cardiac results, IVF fetuses showed larger atria (right atria-to-heart ratio: IVF mean 18.9% (SD 3.4) versus subfertile 17.8% (3.5) versus fertile 17.6% (3.3); adjusted P-value < 0.001), more globular ventricles (right ventricular sphericity index: IVF 1.56 (0.25) versus subfertile 1.72 (0.26) versus fertile 1.72 (0.26); <0.001), and thicker myocardial walls (relative wall thickness: IVF 0.86 (0.22) versus subfertile 0.64 (0.13) versus fertile 0.64 (0.18); <0.001). Whereas SC fetuses from fertile and subfertile couples had preserved cardiac function, IVF fetuses showed signs of suboptimal systolic and diastolic function, with reduced tricuspid ring displacement (IVF 7.26 mm (1.07) versus subfertile 8.04 mm (1.18) versus fertile 7.89 mm (1.51); <0.001) and increased left myocardial performance index (IVF 0.49 (0.08) versus subfertile 0.45 (0.09) versus fertile 0.45 (0.10); <0.001). A sub-analysis including only unexplained infertility cases in subfertile SC and IVF groups showed similar results.

LIMITATIONS, REASONS FOR CAUTION

The fetal cardiac changes reported here are subclinical, and most of the cardiovascular parameters were within normal ranges. Although echocardiographic changes are recognized as potential cardiovascular risk factors, their association with long-term cardiovascular disease remains to be demonstrated.

WIDER IMPLICATIONS OF THE FINDINGS

Subfertility per se does not seem to be associated to fetal cardiac remodeling, which has been previously described in IVF fetuses. Future studies are warranted to further investigate other factors related to the observed fetal cardiac changes associated with ART.

STUDY FUNDING/COMPETING INTEREST(S)

This project has been partially funded with support from the Erasmus + Programme of the European Union (Framework Agreement number: 2013-0040). This publication reflects the views only of the author, and the Commission cannot be held responsible for any use, which may be made of the information contained therein. Additionally, the research leading to these results has received funding from 'la Caixa' Foundation under grant agreement LCF/PR/GN18/10310003, the Instituto de Salud Carlos III (PI15/00130, PI16/00861, PI17/00675, PI18/00073, INT21/00027)-co-funded by the European Union, Cerebra Foundation for the Brain Injured Child (Carmarthen, Wales, UK) and AGAUR 2017 SGR grant no 1531. The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Assessment of myocardial function in infants conceived by assisted reproductive technologies using deformation imaging over the first year of age: A cohort study

BACKGROUND AND AIM

There is emerging evidence of cardiovascular remodeling and functional impairment in individuals conceived via Assisted Reproductive Technologies (ART). The aim of this study was to serially assess myocardial function and pulmonary hemodynamic measurements in infants conceived via ART over the first year of age and to compare them to a cohort of spontaneously conceived controls.

METHODS

This was a prospective, observational study. Echocardiography was performed at Day 2, 6 months and 1 year of age. Biventricular function was assessed by deformation analysis. Pulmonary artery acceleration time (PAAT) and left ventricular (LV) eccentricity index (LVEI) provided surrogate measures of pulmonary vascular resistance (PVR).

RESULTS

Fifty infants conceived via ART were compared to 50 spontaneously conceived controls. There were no differences in baseline infant demographics between the two groups. At 1 year of age right ventricular (RV) basal and RV mid cavity diameters were higher in the ART group. PAATi was lower and LVEI higher in the ART group at 6 months and 1 year. In the ART group, LV global longitudinal strain, LV systolic strain rate, LV early diastolic strain rate and RV free wall strain were lower on Day 2, 6 months, and 1 year of age in comparison to the control group (all p < .05). Within the ART group, on linear regression, maternal age, the type of ART treatment or egg characteristics did not influence PAAT or deformation measurements.

CONCLUSION

Our findings suggest that greater cardiovascular surveillance of ART conceived infants may be warranted.

Cardiac remodeling from the fetus to adulthood

Prenatal cardiac remodeling refers to in utero changes in the fetal heart that occur as a response to an adverse intrauterine environment. In this article, we will review the main mechanisms leading to cardiac remodeling and dysfunction, summarizing and describing the major pathological conditions that have been reported to be related to this in utero plastic adaptive process. We will also recap the current evidence regarding the persistence of fetal cardiac remodeling and dysfunction, both in infancy and later in adult life. Moreover, we will discuss primary, secondary, and tertiary preventive measures and future clinical and research aspects.

Left ventricular systolic function in subjects conceived through assisted reproductive technologies

Background

Over the past decades, assisted reproductive technologies (ART) have gained remarkable influence in the treatment of infertility and account for more than 2 % of births in European countries nowadays. Accumulating evidence suggests ART to cause cardiovascular alterations, including left ventricular (LV) dysfunctions, within its offspring. The aim of this study was to assess LV systolic function in subjects conceived through ART in comparison to spontaneously conceived peers.

Methods

For the assessment of LV morphology and LV function, M-Mode echocardiography, pulsed wave Doppler and two-dimensional speckle tracking echocardiography (2DSTE) were applied. LV ejection fraction (EF) and fractional shortening (FS) were assessed in M-Mode and calculated by Teichholz formula. EF was additionally assessed semiautomatically through 2DSTE.

Results

In total, 64 ART subjects and 83 spontaneously conceived controls with no significant differences in age (12.52 ± 5.64 years vs. 13.20 ± 5.95 years, p = 0.486) and sex were included in the analysis. In the ART cohort, significantly lower values were observed for M-Mode assessed EF (63.63 ± 5.17 % vs. 65.35 ± 5.10 %, p = 0.046) and FS (34.26 ± 3.87 % vs. 35.60 ± 3.84 %, p = 0.038). However, after the adjustment for birth weight percentile and gestational age, M-Mode assessed EF and FS displayed no significant differences between both groups. LV morphology and remaining systolic function parameters, such as mitral annular plane systolic excursion, aortic velocity time integral, global peak longitudinal strain and 2DSTE measured EF, were comparable between both groups.

Conclusion

This study suggests a lower LV systolic function in ART subjects, visualized by significantly lower values for M-Mode assessed EF and FS, compared to spontaneously conceived peers. The clinical relevance of these findings has to be investigated as the above-mentioned parameters were in normal reference range. In addition, LV systolic function parameters evaluated by other echocardiographic imaging modalities were comparable between both groups. Therefore, further studies will be required to evaluate the influence of ART on LV systolic function and cardiovascular morbidity in the future.

Left Ventricular Diastolic Function in Subjects Conceived through Assisted Reproductive Technologies

Subjects conceived through assisted reproductive technologies (ART) potentially suffer from impaired left ventricular (LV) function due to premature vascular aging. This study aimed to evaluate whether subtle differences in LV diastolic function can be observed echocardiographically between young ART subjects and their spontaneously conceived peers. The echocardiographic assessment included the measurement of LV dimensions, mitral inflow velocities, and myocardial velocity at early diastole (E', cm/s) at the LV wall and the interventricular septum (IVS). An average from E/E'LV and E/E'IVS (E/E'AVG) was derived. In total, 66 ART subjects and 83 controls (12.85 ± 5.80 years vs. 13.25 ± 5.89 years, p = 0.677) were included. The ART subjects demonstrated a significantly lower E'LV (19.29 ± 3.29 cm/s vs. 20.67 ± 3.78 cm/s, p = 0.020) compared to their spontaneously conceived peers. Study participants of ≥ 10 years of age displayed a significantly higher E/E'AVG (6.50 ± 0.97 vs. 6.05 ± 0.99, p = 0.035) within the ART cohort. The results of this study demonstrate a significantly lower LV diastolic function in the ART subjects. However, no significant changes in LV diastolic function were observed between the two groups when the results were adjusted for age, birth weight percentile, and gestational age. Those ART subjects born preterm might have an elevated risk of developing LV diastolic alterations and could therefore profit from close echocardiographic monitoring.

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.

The Consequences of Assisted Reproduction Technologies on the Offspring Health Throughout Life: A Placental Contribution

The use of assisted reproductive technologies (ART) worldwide has led to the conception and birth of over eight million babies since being implemented in 1978. ART use is currently on the rise, given growing infertility and the increase in conception age among men and women in industrialized countries. Though obstetric and perinatal outcomes have improved over the years, pregnancies achieved by ART still bear increased risks for the mother and the unborn child. Moreover, given that the first generation of ART offspring is now only reaching their forties, the long-term effects of ART are currently unknown. This is important, as there is a wealth of data showing that life-long health can be predetermined by poor conditions during intrauterine development, including irregularities in the structure and functioning of the placenta. In the current review, we aim to summarize the latest available findings examining the effects of ART on the cardiometabolic, cognitive/neurodevelopmental, and behavioral outcomes in the perinatal period, childhood and adolescence/adulthood; and to examine placental intrinsic factors that may contribute to the developmental outcomes of ART offspring. Altogether, the latest knowledge about life outcomes beyond adolescence for those conceived by ART appears to suggest a better long-term outcome than previously predicted. There are also changes in placenta structure and functional capacity with ART. However, more work in this area is critically required, since the potential consequences of ART may still emerge as the offspring gets older. In addition, knowledge of the placenta may help to foresee and mitigate any adverse outcomes in the offspring.

Epigenetic Risks of Medically Assisted Reproduction

Since the birth of Louise Joy Brown, the first baby conceived via in vitro fertilization, more than 9 million children have been born worldwide using assisted reproductive technologies (ART). In vivo fertilization takes place in the maternal oviduct, where the unique physiological conditions guarantee the healthy development of the embryo. During early embryogenesis, a major wave of epigenetic reprogramming takes place that is crucial for the correct development of the embryo. Epigenetic reprogramming is susceptible to environmental changes and non-physiological conditions such as those applied during in vitro culture, including shift in pH and temperature, oxygen tension, controlled ovarian stimulation, intracytoplasmic sperm injection, as well as preimplantation embryo manipulations for genetic testing. In the last decade, concerns were raised of a possible link between ART and increased incidence of imprinting disorders, as well as epigenetic alterations in the germ cells of infertile parents that are transmitted to the offspring following ART. The aim of this review was to present evidence from the literature regarding epigenetic errors linked to assisted reproduction treatments and their consequences on the conceived children. Furthermore, we provide an overview of disease risk associated with epigenetic or imprinting alterations in children born via ART.

The association between assisted reproductive technology and cardiac remodeling in fetuses and early infants: a prospective cohort study

BACKGROUND

Limited data exist regarding the potential impact of assisted reproductive technology (ART) on cardiac remodeling. In particular, whether different ART techniques are related to different cardiac alterations remains unclear. We aimed to evaluate cardiac changes in fetuses and infants arising from ART and fetal cardiac alterations in fetuses conceived by specific ART procedures.

METHODS

This prospective and observational cohort study recruited 111 fetuses conceived by ART and 106 spontaneously conceived controls between December 2017 and April 2019. Echocardiography was performed between 28⁺⁰ and 32⁺⁶ weeks-of-gestation and at 0-2 and 6 months after birth.

RESULTS

A total of 88 ART fetuses and 85 controls were included in the final analysis. Compared to controls, ART fetuses demonstrated a globular enlarged left ventricle (LV) (LV sphericity index of mid-section, 2.29 ± 0.34 vs. 2.45 ± 0.39, P = 0.006; LV area, 262.33 ± 45.96 mm² vs. 244.25 ± 47.13 mm², P = 0.002), a larger right ventricle (RV) (RV area, 236.10 ± 38.63 mm² vs. 221.14 ± 42.60 mm², P = 0.003) and reduced LV systolic deformation (LV global longitudinal strain (GLS), -19.56% ± 1.90% vs. -20.65% ± 1.88%, P = 0.013; LV GLS rate S, -3.32 ± 0.36 s^-1 vs. -3.58 ± 0.39 s^-1, P = 0.023). There were no significant differences between the ART and control groups at postnatal follow-ups. Furthermore, we found fetal cardiac morphometry and function were comparable between different ART procedures. Compared to controls, the fetuses derived from various ART procedures all exhibited impairments in the LV GLS and the LV GLS rate S.

CONCLUSIONS

Our analysis demonstrated that subclinical cardiac remodeling and dysfunction were evident in ART fetuses, although these alterations did not persist in early infancy. In addition, various ART procedures may cause the same unfavorable changes in the fetal heart.

TRIAL REGISTRATION

This trial was registered at the Chinese Clinical Trial Registry ( www.chictr.org.cn ) ( ChiCTR1900021672 ) on March 4, 2019, retrospectively registered.

Melatonin supplementation in the culture medium rescues impaired glucose metabolism in IVF mice offspring

Increasing evidence suggests that in vitro fertilization (IVF) may be associated with an increased risk of developing obesity and metabolic diseases later in life in the offspring. Notably, the addition of melatonin to culture medium may improve embryo development and prevent cardiovascular dysfunction in IVF adult mice. This study aimed to determine if melatonin supplementation in the culture medium can reverse impaired glucose metabolism in IVF mice offspring and the underlying mechanisms. Blastocysts used for transfer were generated by natural mating (control group) or IVF with or without melatonin (10^-6  M) supplementation (mIVF and IVF group, respectively) in clinical-grade culture media. Here, we first report that IVF decreased hepatic expression of Fbxl7, which was associated with impaired glucose metabolism in mice offspring. Melatonin addition reversed the phenotype by up-regulating the expression of hepatic Fbxl7. In vitro experiments showed that Fbxl7 enhanced the insulin signaling pathway by degrading RhoA through ubiquitination and was up-regulated by transcription factor Foxa2. Specific knockout of Fbxl7 in the liver of adult mice, through tail intravenous injection of recombinant adeno-associated virus, impaired glucose tolerance, while overexpression of hepatic Fbxl7 significantly improved glucose tolerance in adult IVF mice. Thus, the data suggest that Fbxl7 plays an important role in maintaining glucose metabolism of mice, and melatonin supplementation in the culture medium may rescue the long-term risk of metabolic diseases in IVF offspring.

Assessment of Cardiovascular Health of Children Ages 6 to 10 Years Conceived by Assisted Reproductive Technology

IMPORTANCE

Assisted reproductive technology (ART) has been widely used for treatment of infertility and has brought millions of births worldwide. The health of offspring conceived by ART has been of much concern, and adverse cardiovascular health outcomes have been reported by previous studies.

OBJECTIVE

To assess the cardiovascular health of children conceived by ART.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted among participants recruited from November 2017 to February 2019. Participants were 382 children conceived by ART who were selected from a single reproductive center and 382 children who were naturally conceived, randomly selected from a primary school, and matched by sex, age, and maternal age at the child's birth (2 years older or younger). Data were analyzed from March 2019 through December 2019.

EXPOSURES

Conception by ART.

MAIN OUTCOMES AND MEASURES

Blood pressure was measured, and echocardiography was performed to determine left ventricular structural and functional parameters. Adjusted relative wall thickness (aRWT) was found for age, with high RWT defined as an aRWT of 0.375 or more.

RESULTS

Among 764 children aged 6 to 10 years, 382 children were conceived by ART (mean [SD] age, 7.20 [1.21] years; 201 [52.6%] boys) and 382 children were naturally conceived (mean [SD] age, 7.20 [1.21] years; 201 [52.6%] boys). Children conceived by ART had statistically significantly increased mean (SD) height (130.2 [9.5] cm vs 128.5 [8.1] cm; P = .007) and body mass index (17.6 [3.6] vs 17.1 [2.7]; P = .03). Those conceived by ART, compared with children in the matched control group, had statistically significantly increased blood pressure (mean [SD] systolic blood pressure, 105.5 [6.9] mm Hg vs 103.5 [8.4] mm Hg; adjusted P < .001; mean [SD] diastolic blood pressure, 67.2 [5.6] mm Hg vs 62.2 [6.3] mm Hg ; adjusted P < .001), left ventricular systolic dysfunction (mean [SD] left ventricular ejection fraction, 64.61% [3.20%] vs 66.70% [3.89%]; adjusted P < .001), and diastolic dysfunction (mean [SD] early/late mitral/tricuspid diastolic velocities ratio, 1.66 [0.28] vs 2.21 [0.36]; adjusted P < .001). They also had statistically significantly increased parameters of left ventricular structure, including mean (SD) left ventricular mass index (31.97 [5.04] g/m2.7 vs 28.28 [3.54] g/m2.7; adjusted P < .001) and RWT (3.30 [0.41] mm vs 2.98 [0.14] mm; adjusted P < .001). Additionally, children conceived by ART had statistically significantly increased prevalence of left ventricular hypertrophy (9 children [2.4%] vs 2 children [0.5%]; P = .03), high RWT (61 children [16.0%] vs 0 children; P < .001), and left ventricle remodeling patterns, including concentric remodeling (60 children [15.7%] vs 0 children), eccentric hypertrophy (8 children [2.1%] vs 2 children [0.5%]), and concentric hypertrophy (1 child [0.3%] vs 0 children) (P for left ventricle remodeling < .001).

CONCLUSIONS AND RELEVANCE

This study found that children conceived by ART had increased blood pressure and unfavorable changes in left ventricular structure and function compared with children who were naturally conceived. These findings suggest that further studies are needed to investigate the potential mechanisms and long-term outcomes associated with these differences.

Outcomes of Very Preterm Infants Conceived with Assisted Reproductive Technologies

OBJECTIVE

To compare mortality and early respiratory outcomes of very preterm infants conceived via assisted reproductive technology (ART) vs spontaneously.

STUDY DESIGN

We identified inborn infants (July 2014-July 2019) with gestational age <32 weeks (n = 439); 54 cases were ART conceived. Spontaneously conceived controls (n = 103) were matched by multiple gestation status and gestational age. Primary outcome was 1-year mortality. Secondary outcomes were receipt of respiratory support and supplemental oxygen at 7 and 28 days and 36 weeks of postmenstrual age. We evaluated the association between conception method and outcomes by logistic regression, with adjustment for sociodemographic status.

RESULTS

Women who conceived via ART had increased rates of prepregnancy and gestational diabetes, and no differences in rates of hypertensive disorders. Infant 1-year mortality was not different by mode of conception (ART 11.8% vs spontaneous 7.1%, P = .49). Infants conceived by ART were less likely to receive respiratory support or supplemental oxygen at all time points, but this relationship only reached significance for receipt of oxygen at 28 days (ART 20.8% vs spontaneous 39.0%, P = .03); this remained true after adjustment for race/ethnicity and socioeconomic index.

CONCLUSIONS

When controlling for gestational age and multiple gestation status, very preterm infants conceived following ART had similar outcomes as those conceived spontaneously.

Cardiac remodeling in fetuses conceived by ARTs: fresh versus frozen embryo transfer

STUDY QUESTION

Do fetuses from frozen embryo transfer (FET) present signs of cardiac remodeling and suboptimal function similar to those observed in fetuses from fresh embryo transfer (ET)?

SUMMARY ANSWER

Fetuses from both fresh ET and FET present signs of fetal cardiac remodeling and suboptimal function, with more pronounced changes after fresh ET as compared to FET.

WHAT IS KNOWN ALREADY

Our group and others have previously demonstrated that fetuses and children conceived by ARTs present cardiac remodeling and suboptimal function. These fetuses show dilated atria, more globular and thicker ventricles, reduced longitudinal motion, and impaired relaxation. Cardiac changes were already present in utero and persisted after birth. Most of the ART fetuses included in previous publications were from fresh ET. However, singletons from FET have different perinatal outcomes compared to those from fresh ET. There are no previous studies comparing cardiac morphology and function between fetuses following fresh and FET.

STUDY DESIGN, SIZE, DURATION

This is a prospective cohort study of 300 singleton pregnancies recruited from 2017 to 2020, including 100 spontaneously conceived (SC) pregnancies, 100 fetuses conceived by IVF with FET, and 100 fetuses conceived by IVF with fresh ET. Fetal structural and functional echocardiography was performed in all pregnancies.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Pregnancies conceived by IVF were recruited from a single assisted reproduction center, ensuring homogeneity in IVF stimulation protocols, endometrial preparation for FET, laboratory procedures, and embryo culture conditions. SC pregnancies from fertile couples were selected from the general population and matched to IVF pregnancies by maternal age. Epidemiological and perinatal outcomes were collected in all cases. Fetal echocardiography was performed at 28-33 weeks of pregnancy to assess cardiac structure and function in all pregnancies. All echocardiographic comparisons were adjusted by maternal age, nulliparity, birthweight centile, preeclampsia, and prematurity.

MAIN RESULTS AND THE ROLE OF CHANCE

Parental age, ethnicity, body mass index and smoking were similar among the study groups. Median gestational age at echocardiography and estimated fetal weight were similar in all study groups. Both fresh ET and FET groups showed similar fetal echocardiographic changes, with more pronounced features in the fresh ET as compared to FET pregnancies. Fetuses conceived by IVF showed larger atria (right atria-to-heart ratio: fresh ET mean 18.1% (SD 3.2) vs FET 18.0% (3.9) vs SC 17.3% (3.2); linear tendency P-value <0.001), more globular ventricles (right ventricular sphericity index: fresh ET 1.62 (0.29) vs FET 1.61 (0.25) vs SC 1.68 (0.26); <0.001) and thicker myocardial walls (relative wall thickness: fresh ET 0.79 (0.21) vs FET 0.74 (0.22) vs SC 0.65 (0.25); <0.001) as compared to SC pregnancies. Both fresh ET and FET groups also had signs of suboptimal systolic and diastolic function, with reduced tricuspid annular systolic peak velocity (fresh ET 7.17 cm/s (1.22) vs FET 7.41 cm/s (1.19) vs SC 7.58 cm/s (1.32); <0.001) and increased left myocardial performance index (fresh ET 0.53 (0.08) vs FET 0.53 (0.08) vs SC 0.50 (0.09); <0.001) as compared to SC pregnancies.

LIMITATIONS, REASONS FOR CAUTION

The cardiac changes reported here are subclinical, with most cardiovascular indexes lying within normal ranges. Although echocardiographic changes are recognized as potential cardiovascular risk factors, their association with the long-term cardiovascular disease remains to be proven. The observed milder fetal cardiac features in FET fetuses cannot condition the choice of this technique and must be considered together with the global perinatal results related to these gestations.

WIDER IMPLICATIONS OF THE FINDINGS

The identification of cardiac remodeling in fetuses conceived by IVF with fresh ET and FET represents an opportunity for early detection. Future studies are warranted to study the potential long-term consequences of these findings.

STUDY FUNDING/COMPETING INTEREST(S)

This project has been partially funded with support from the Erasmus + Programme of the European Union (Framework Agreement number: 2013-0040). This publication reflects the views only of the author, and the Commission cannot be held responsible for any use, which may be made of the information contained therein. Additionally, the research leading to these results has received funding from 'la Caixa' Foundation under grant agreement LCF/PR/GN18/10310003, the Instituto de Salud Carlos III (PI15/00130, PI17/00675, PI18/00073) integrated into the Plan Nacional de I + D+I and cofinanced by ISCIII-Subdirección General de Evaluación and Fondo Europeo de Desarrollo Regional (FEDER) 'Una manera de hacer Europa', Cerebra Foundation for the Brain Injured Child (Carmarthen, Wales, UK) and AGAUR 2017 SGR grant n° 1531. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

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.

The association between in vitro fertilization and intracytoplasmic sperm injection treatment and the risk of congenital heart defects

OBJECTIVE

Assisted reproductive technology (ART), an effective treatment modality for infertility, is associated with a higher prevalence of congenital anomalies such as congenital heart defects (CHDs). The present study aimed to evaluate data linking CHDs in infants to pregnancies resulting from in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI).

METHODS

In this study, we conducted a systematic literature search on CHDs in infants following IVF/ICSI in Google Scholar, Embase, Scopus, MEDLINE, and PubMed databases from inception to February 2020. The search strategy used combinations of search keywords that included assisted reproductive technology/ART, in vitro fertilization/IVF, intracytoplasmic sperm injection/ICSI, birth defect, congenital malformation, and congenital heart defects.

RESULTS

Fifty-six studies fulfilled the inclusion criteria and were selected in the current systematic review, which assessed the association between ART and the risk of CHDs.

CONCLUSION

Children conceived by IVF/ICSI manifested an increased risk of CHDs compared with spontaneously conceived children. Further studies are needed to assess the long-term cardiovascular safety of these techniques, which is important for the counseling of patients before the use of ART.

DNA methylation profile of liver of mice conceived by in vitro fertilization

Offspring generated by in vitro fertilization (IVF) are believed to be healthy but display a possible predisposition to chronic diseases, like hypertension and glucose intolerance. Since epigenetic changes are believed to underlie such phenotype, this study aimed at describing global DNA methylation changes in the liver of adult mice generated by natural mating (FB group) or by IVF. Embryos were generated by IVF or natural mating. At 30 weeks of age, mice were sacrificed. The liver was removed, and global DNA methylation was assessed using whole-genome bisulfite sequencing (WGBS). Genomic Regions for Enrichment Analysis Tool (GREAT) and G:Profilerβ were used to identify differentially methylated regions (DMRs) and for functional enrichment analysis. Overrepresented gene ontology terms were summarized with REVIGO, while canonical pathways (CPs) were identified with Ingenuity® Pathway Analysis. Overall, 2692 DMRs (4.91%) were different between the groups. The majority of DMRs (84.92%) were hypomethylated in the IVF group. Surprisingly, only 0.16% of CpG islands were differentially methylated and only a few DMRs were located on known gene promoters (n = 283) or enhancers (n = 190). Notably, the long-interspersed element (LINE), short-interspersed element (SINE), and long terminal repeat (LTR1) transposable elements showed reduced methylation (P < 0.05) in IVF livers. Cellular metabolic process, hepatic fibrosis, and insulin receptor signaling were some of the principal biological processes and CPs modified by IVF. In summary, IVF modifies the DNA methylation signature in the adult liver, resulting in hypomethylation of genes involved in metabolism and gene transcription regulation. These findings may shed light on the mechanisms underlying the developmental origin of health and disease.

The duration of embryo culture after mouse IVF differentially affects cardiovascular and metabolic health in male offspring

STUDY QUESTION

Do the long-term health outcomes following IVF differ depending upon the duration of embryo culture before transfer?

SUMMARY ANSWER

Using a mouse model, we demonstrate that in male but not female offspring, adverse cardiovascular (CV) health was more likely with prolonged culture to the blastocyst stage, but metabolic dysfunction was more likely if embryo transfer (ET) occurred at the early cleavage stage.

WHAT IS KNOWN ALREADY

ART associate with increased risk of adverse CV and metabolic health in offspring, and these findings have been confirmed in animal models in the absence of parental infertility issues. It is unclear which specific ART treatments may cause these risks. There is increasing use of blastocyst, versus cleavage-stage, transfer in clinical ART which does not appear to impair perinatal health of children born, but the longer-term health implications are unknown.

STUDY DESIGN, SIZE, DURATION

Five mouse groups were generated comprising: (i) natural mating (NM)—naturally mated, non-superovulated and undisturbed gestation; (ii) IV-ET-2Cell—in-vivo derived two-cell embryos collected from superovulated mothers, with immediate ET to recipients; (iii) IVF-ET-2Cell—IVF generated embryos, from oocytes from superovulated mothers, cultured to the two-cell stage before ET to recipients; (iv) IV-ET-BL—in-vivo derived blastocysts collected from superovulated mothers, with immediate ET to recipients; (v) IVF-ET-BL—IVF generated embryos, from oocytes from superovulated mothers, cultured to the blastocyst stage before ET to recipients. Both male and female offspring were analysed for growth, CV and metabolic markers of health. There were 8–13 litters generated for each group for analyses; postnatal data were analysed by multilevel random effects regression to take account of between-mother and within-mother variation and litter size.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

C57/BL6 female mice (3–4 weeks old) were used for oocyte production; CBA males for sperm with human tubal fluid medium were used for IVF. Embryos were transferred (ET) to MF1 pseudo-pregnant recipients at the two-cell stage or cultured in synthetic oviductal medium enriched with potassium medium to the blastocyst stage before ET. Control in-vivo embryos from C57BL6 × CBA matings were collected and immediately transferred at the two-cell or blastocyst stage. Postnatal assays included growth rate up to 27 weeks; systolic blood pressure (SBP) at 9, 15 and 21 weeks; lung and serum angiotensin-converting enzyme (ACE) activity at time of cull (27 weeks); glucose tolerance test (GTT; 27 weeks); basal glucose and insulin levels (27 weeks); and lipid accumulation in liver cryosections using Oil Red O imaging (27 weeks).

MAIN RESULTS AND THE ROLE OF CHANCE

Blastocysts formed by IVF developed at a slower rate and comprised fewer cells that in-vivo generated blastocysts without culture (P < 0.05). Postnatal growth rate was increased in all four experimental treatments compared with NM group (P < 0.05). SBP, serum and lung ACE and heart/body weight were higher in IVF-ET-BL versus IVF-ET-2Cell males (P < 0.05) and higher than in other treatment groups, with SBP and lung ACE positively correlated (P < 0.05). Glucose handling (GTT AUC) was poorer and basal insulin levels were higher in IVF-ET-2Cell males than in IVF-ET-BL (P < 0.05) with the glucose:insulin ratio more negatively correlated with body weight in IVF-ET-2Cell males than in other groups. Liver/body weight and liver lipid droplet diameter and density in IVF-ET-2Cell males were higher than in IVF-ET-BL males (P < 0.05). IVF groups had poorer health characteristics than their in-vivo control groups, indicating that outcomes were not caused specifically by background techniques (superovulation, ET). No consistent health effects from duration of culture were identified in female offspring.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Results from experimental animal models cannot be extrapolated to humans. Nevertheless, they are valuable to develop conceptual models, in this case, in the absence of confounding parental infertility, in assessing the safety of ART manipulations.

WIDER IMPLICATIONS OF THE FINDINGS

The study indicates that longer duration of embryo culture after IVF up to blastocyst before ET leads to increased dysfunction of CV health in males compared with IVF and shorter cleavage-stage ET. However, the metabolic health of male offspring was poorer after shorter versus longer culture duration. This distinction indicates that the origin of CV and metabolic health phenotypes after ART may be different. The poorer metabolic health of males after cleavage-stage ET coincides with embryonic genome activation occurring at the time of ET.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported through the European Union FP7-CP-FP Epihealth programme (278418) and FP7-PEOPLE-2012-ITN EpiHealthNet programme (317146) to T.P.F., the Biotechnology and Biological Sciences Research Council (BBSRC) (BB/F007450/1) to T.P.F., and the Saudi government, University of Jeddah and King Abdulaziz University to A.A. The authors have no conflicts of interest to declare.

Placental diseases associated with assisted reproductive technology

The placenta develops from the outer trophoblastic layer following the differentiation of the fertilized ovum and is therefore more susceptible to epigenetic regulatory changes caused by environmental interventions and influences during assisted reproductive technology. Furthermore, the placenta regulates the development of the fetal heart, brain, kidneys, bones, and other tissues and organs [1]. Placental dysplasia leads to poor perinatal outcomes as well as long-term health risks later in life, including neurodevelopmental disorders, tumors, and adult metabolic syndrome [2,3]. In view of the decisive role of the placenta during intrauterine fetal development, Graham J. Burton, an expert in placentology from the University of Cambridge, formally proposed the theory of "placenta-derived chronic diseases" in 2018 based on embryonic-derived diseases [4]. In this review, we summarized the changes in placental morphology and structure, growth dynamics, imprinted and non-imprinted genes, and other aspects attributable to assisted reproduction technology. Our review provides a theoretical basis for further research on placental changes caused by assisted reproductive technology that are most strongly associated with an increased risk of neonatal long-term diseases.

Pulmonary Hypertension in Acute and Chronic High Altitude Maladaptation Disorders

Alveolar hypoxia is the most prominent feature of high altitude environment with well-known consequences for the cardio-pulmonary system, including development of pulmonary hypertension. Pulmonary hypertension due to an exaggerated hypoxic pulmonary vasoconstriction contributes to high altitude pulmonary edema (HAPE), a life-threatening disorder, occurring at high altitudes in non-acclimatized healthy individuals. Despite a strong physiologic rationale for using vasodilators for prevention and treatment of HAPE, no systematic studies of their efficacy have been conducted to date. Calcium-channel blockers are currently recommended for drug prophylaxis in high-risk individuals with a clear history of recurrent HAPE based on the extensive clinical experience with nifedipine in HAPE prevention in susceptible individuals. Chronic exposure to hypoxia induces pulmonary vascular remodeling and development of pulmonary hypertension, which places an increased pressure load on the right ventricle leading to right heart failure. Further, pulmonary hypertension along with excessive erythrocytosis may complicate chronic mountain sickness, another high altitude maladaptation disorder. Importantly, other causes than hypoxia may potentially underlie and/or contribute to pulmonary hypertension at high altitude, such as chronic heart and lung diseases, thrombotic or embolic diseases. Extensive clinical experience with drugs in patients with pulmonary arterial hypertension suggests their potential for treatment of high altitude pulmonary hypertension. Small studies have demonstrated their efficacy in reducing pulmonary artery pressure in high altitude residents. However, no drugs have been approved to date for the therapy of chronic high altitude pulmonary hypertension. This work provides a literature review on the role of pulmonary hypertension in the pathogenesis of acute and chronic high altitude maladaptation disorders and summarizes current knowledge regarding potential treatment options.

Reducing time to pregnancy and facilitating the birth of healthy children through functional analysis of embryo physiology†

An ever-increasing number of couples rely on assisted reproductive technologies (ART) in order to conceive a child. Although advances in embryo culture have led to increases in the success rates of clinical ART, it often takes more than one treatment cycle to conceive a child. Ensuring patients conceive as soon as possible with a healthy embryo is a priority for reproductive medicine. Currently, selection of embryos for transfer relies predominantly on the morphological assessment of the preimplantation embryo; however, morphology is not an absolute link to embryo physiology, nor the health of the resulting child. Non-invasive quantitation of individual embryo physiology, a key regulator of both embryo viability and health, could provide valuable information to assist in the selection of the most viable embryo for transfer, hence reducing the time to pregnancy. Further, according to the Barker Hypothesis, the environment to which a fetus is exposed to during gestation affects subsequent offspring health. If the environment of the preimplantation period is capable of affecting metabolism, which in turn will affect gene expression through the metaboloepigenetic link, then assessment of embryo metabolism should represent an indirect measure of future offspring health. Previously, the term viable embryo has been used in association with the potential of an embryo to establish a pregnancy. Here, we propose the term healthy embryo to reflect the capacity of that embryo to lead to a healthy child and adult.

Early Life Oxidative Stress and Long-Lasting Cardiovascular Effects on Offspring Conceived by Assisted Reproductive Technologies: A Review

Assisted reproductive technology (ART) has rapidly developed and is now widely practised worldwide. Both the characteristics of ART (handling gametes/embryos in vitro) and the infertility backgrounds of ART parents (such as infertility diseases and unfavourable lifestyles or diets) could cause increased oxidative stress (OS) that may exert adverse influences on gametogenesis, fertilisation, and foetation, even causing a long-lasting influence on the offspring. For these reasons, the safety of ART needs to be closely examined. In this review, from an ART safety standpoint, the origins of OS are reviewed, and the long-lasting cardiovascular effects and potential mechanisms of OS on the offspring are discussed.

Vascular Health of Children Conceived via In Vitro Fertilization

OBJECTIVE

To evaluate whether in vitro fertilization (IVF) has an effect on the cardiovascular health of offspring.

STUDY DESIGN

This was a cross-sectional pilot study. We performed vascular health assessment for 17 children aged 10-14 years who were conceived via IVF with autologous oocytes at Stanford University. Carotid artery ultrasound evaluated intima-media thickness and stiffness, carotid-femoral pulse wave velocity determined segmental arterial stiffness, and endothelial pulse amplitude testing assessed endothelial function. We compared IVF offspring with control adolescents assessed in the same laboratory, with all comparisons adjusted for age, sex, and race/ethnicity.

RESULTS

All participants had normal body mass index and blood pressure. Compared with controls, IVF children had thicker common carotid artery intima-media thickness (0.44 ± 0.03 mm vs 0.38 ± 0.03 mm; P < .01), higher elastic modulus (395.29 ± 185.33 mm Hg vs 242.79 ± 37.69 mm Hg; P = .01), higher βstiffness (2.65 ± 0.38 vs 2.28 ± 0.23; P < .01), and higher peak velocity (142.29 ± 31.62 cm/s vs 117.71 ± 32.69 cm/s; P = .04). The mean endothelial pulse amplitude testing reactive hyperemia index was not significantly different between IVF and controls. The mean pulse wave velocity was 4.69 ± 0.51 m/s compared with the controls 4.60 ± 0.57 m/s (P = .11), with 8 (47%) having abnormal values.

CONCLUSION

In an assessment of endothelial function and arterial properties of children conceived via IVF, we found that children conceived via IVF seem to have evidence of abnormal vascular health. Further studies with larger sample size and long-term follow-up are warranted.

Outcomes of pulmonary vascular disease in infants conceived with non-IVF fertility treatment and assisted reproductive technologies at 1 year of age

BACKGROUND

Assisted reproductive technologies (ARTs) have been associated with the development of endothelial dysfunction.

OBJECTIVE

To determine potential differences in outcomes associated with pulmonary vascular disease in infants born to mothers receiving any infertility treatment including ART and non-IVF fertility treatments (NIFTs).

DESIGN/METHODS

The sample was derived from an administrative database containing detailed information on infant and maternal characteristics for live-born infants in California (2007-2012) with gestational age (GA) 22 to 44 weeks. Cases were defined as infants with ICD-9 code for pulmonary vascular disease (PVD) and records for ART/NIFT. Controls were randomly selected at a 1:4 ratio. The primary outcome was 1-year mortality. Crude and adjusted odds ratio (OR) with 95% confidence interval (CI) were calculated.

RESULTS

We identified 159 cases and 636 controls. Mothers that utilized ART/NIFT were older, to be of the Caucasian race, to have pre-eclampsia, private insurance, and education >12 years (P < .001). Cases compared to controls were more premature, had lower birth weights, and were more often the product of a multiple gestation pregnancy (P < .001). Cases had a higher 1-year mortality (18.2% vs 9.1%; OR: 2.2; 95% CI: 1.4, 3.6), more severe PVD (86.2% vs 72.3%; OR: 2.4; 95% CI: 1.5, 3.9), and a longer hospital stay (66.7 ± 73.0 vs 32.5 ± 47.2 days; P < .001) than controls. However, when adjusting for GA these differences become statistically insignificant.

CONCLUSION

Children born following ART/NIFT with PVD had increased mortality compared to infants with PVD but without ART/NIFT. The primary driver of this relationship is prematurity.

Assessing cardiovascular remodelling in fetuses and infants conceived by assisted reproductive technologies: a prospective observational cohort study protocol

INTRODUCTION

Assisted reproductive technologies (ART), namely in vitro fertilisation and intracytoplasmic sperm injection, have become widely used to treat infertility. Although the use of ART is generally considered favourable, there are ongoing concerns about the prenatal and perinatal risks as well as long-term risks for the child. Epidemiological studies have demonstrated an association between pathological events during fetal development and future cardiovascular risk, raising concerns about cardiovascular remodelling in fetuses conceived by ART. The authors hypothesise fetuses conceived by ART present signs of cardioventricular dysfunction, which can be detected by deformation analysis. To address these issues, we will assess comprehensive cardiovascular structure and function in ART offspring and explore the role of speckle-tracking in myocardial deformation.

METHODS AND ANALYSIS

This prospective observational cohort study will include 100 singleton pregnancies conceived by ART and 100 controls identified in fetal life and followed up to 6 months old. At inclusion, a baseline assessment of the mothers and ART characteristics will be recorded by interview and review of medical records. Between 28 and 32 weeks gestation, a detailed fetal echography will be performed, including an assessment of estimated fetal weight, fetoplacental Doppler, fetal echocardiography and fetal abdominal artery ultrasound. On delivery, maternal and neonatal characteristics will be assessed. Within 60 days of birth, the first postnatal cardiovascular assessment will be conducted which will include echocardiography and abdominal artery ultrasound. At 6 months of age, the second infants' follow-up evaluation will include the weight and length of the infant, echocardiography and abdominal artery ultrasound. Data will be presented as mean±SD, median or percentages where appropriate. A p<0.05 will be considered statistically significant.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethics Committee of Shengjing Hospital of China Medical University. Findings will be disseminated through scientific publications and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR1900021672.

Epigenetic Modulation in the Initiation and Progression of Pulmonary Hypertension

Pulmonary hypertension (PH) is a severe disease with multiple etiologies. In addition to genetics, recent studies have revealed the epigenetic modulation in the initiation and progression of PH. In this review, we summarize the epigenetic mechanisms in the pathogenesis of PH, specifically, DNA methylation, histone modifications, and microRNAs. We further emphasize the diagnostic and therapeutic potential of these epigenetic hallmarks in PH. Finally, we highlight the developmental reprogramming in adult-onset PH because of adverse perinatal exposures such as intrauterine growth restriction and extrauterine growth restriction. Therefore, epigenetic modifications provide promise for the therapy and prevention of PH.

Association of Assisted Reproductive Technologies With Arterial Hypertension During Adolescence

BACKGROUND

Assisted reproductive technologies (ART) have been shown to induce premature vascular aging in apparently healthy children. In mice, ART-induced premature vascular aging evolves into arterial hypertension. Given the young age of the human ART group, long-term sequelae of ART-induced alterations of the cardiovascular phenotype are unknown.

OBJECTIVES

This study hypothesized that vascular alterations persist in adolescents and young adults conceived by ART and that arterial hypertension possibly represents the first detectable clinically relevant endpoint in this group.

METHODS

Five years after the initial assessment, the study investigators reassessed vascular function and performed 24-h ambulatory blood pressure (BP) monitoring (ABPM) in 54 young, apparently healthy participants conceived through ART and 43 age- and sex-matched controls.

RESULTS

Premature vascular aging persisted in ART-conceived subjects, as evidenced by a roughly 25% impairment of flow-mediated dilation of the brachial artery (p < 0.001) and increased pulse-wave velocity and carotid intima-media thickness. Most importantly, ABPM values (systolic BP, 119.8 ± 9.1 mm Hg vs. 115.7 ± 7.0 mm Hg, p = 0.03; diastolic BP, 71.4 ± 6.1 mm Hg vs. 69.1 ± 4.2 mm Hg, p = 0.02 ART vs. control) and BP variability were markedly higher in ART-conceived subjects than in control subjects. Eight of the 52 ART participants, but only 1 of the 43 control participants (p = 0.041 ART vs. controls) fulfilled ABPM criteria of arterial hypertension (>130/80 mm Hg and/or >95th percentile).

CONCLUSIONS

ART-induced premature vascular aging persists in apparently healthy adolescents and young adults without any other detectable classical cardiovascular risk factors and progresses to arterial hypertension. (Vascular Dysfunction in Offspring of Assisted Reproduction Technologies; NCT00837642.).

Methylation-reprogrammed AGTR1 results in increased vasoconstriction by angiotensin II in human umbilical cord vessel following in vitro fertilization-embryo transfer

AIMS

Assisted reproductive technologies (ART) have been widely used to treat infertility, which may impact on fetuses and offspring. This study investigated the effects of in vitro fertilization-embryo transfer (IVF-ET) on angiotensin II (AII)-mediated vasoconstrictions in umbilical cord vein, and explored possible reprogrammed methylation mechanism.

MATERIALS AND METHODS

Human umbilical cords were randomly divided into ordinary pregnancy and IVF-ET pregnancy. Vascular studies with AII as well as its specific receptor antagonists losartan and PD123,319 were conducted. Real-time quantitative PCR, Western blotting, and methylation analysis by bisulfite sequencing were performed with the cord vessel samples.

KEY FINDINGS

In IVF-ET group, the maximal response to AII in umbilical vessels was significantly greater than that in the ordinary pregnancy. Using losartan and PD123,319, angiotensin receptor subtype 1 (AT1R) was found mainly responsible for the enhanced contraction in the umbilical vein of IVF-ET pregnancy. Decreased mRNA expression of DNMT3A was found in umbilical vein of IVF-ET group. Hypomethylation of the AGTR1 gene (gene encoding AT1R) in the umbilical veins of the IVF group was found. The data suggested that the IVF-ET treatments altered AII-mediated vasoconstrictions in umbilical veins, which could be partially attributed to the increased expression of AT1R.

SIGNIFICANCE

The hypo-methylation of the AGTR1 gene caused by IVF-ET might play important roles in altered vasoconstrictions, impacting on cardiovascular systems in the long run.

Decreased pulmonary vascular distensibility in adolescents conceived by in vitro fertilization

STUDY QUESTION

What is the functional relevance of decreased pulmonary vascular distensibility in adolescents conceived by IVF?

SUMMARY ANSWER

Children born by IVF have a slight decrease in pulmonary vascular distensibility observed during normoxic exercise that is not associated with altered right ventricular function and aerobic exercise capacity.

WHAT IS KNOWN ALREADY

General vascular dysfunction and increased hypoxic pulmonary hypertension have been reported in ART children as compared to controls. Pulmonary hypertension or decreased pulmonary vascular distensibility may affect right ventricular function and thereby possibly limit maximal cardiac output and aerobic exercise capacity.

STUDY DESIGN, SIZE, DURATION

This prospective case-control study enrolled 15 apparently healthy adolescents conceived by IVF/ICSI after fresh embryo transfer paired in a 2 to 1 ratio to 30 naturally conceived adolescents between March 2015 and May 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Fifteen IVF/ICSI adolescents and 30 controls from singleton gestations matched by age, gender, weight, height and physical activity underwent exercise echocardiography, lung diffusion capacity measurements and a cycloergometer cardiopulmonary exercise test. A pulmonary vascular distensibility coefficient α was determined from the pulmonary arterial pressure (PAP) versus cardiac output (Q) relationships. Pulmonary capillary volume (Vc) was calculated from single breath nitric oxide and carbon monoxide lung diffusion capacity measurements (DLCO and DLNO) at rest and during exercise (100 W). Eight of the IVF subjects and eight controls underwent a 30 min hypoxic challenge at rest with a fraction of inspired oxygen of 0.12 to assess hypoxic pulmonary vasoconstriction.

MAIN RESULTS AND THE ROLE OF CHANCE

In normoxia, oxygen uptake (VO2), blood pressure, DLCO, DLNO, echocardiographic indices of right ventricular function, Q and PAP at rest and during exercise were similar in both groups. However, IVF children had a lower pulmonary vascular distensibility coefficient α (1.2 ± 0.3 versus 1.5 ± 0.3%/mmHg, P = 0.02) and a blunted exercise-induced increase in Vc (24 versus 32%, P < 0.05). Hypoxic-induced increase in pulmonary vascular resistance in eight IVF subjects versus eight controls was similar.

LIMITATIONS, REASONS FOR CAUTION

The IVF cohort was small, and thus type I or II errors could have occurred in spite of careful matching of each case with two controls. ART evolved over the years, so that it is not certain that the presently reported subtle changes will be reproducible in the future. As the study was limited to singletons born after fresh embryo transfers, our observations cannot be extrapolated to singletons born after frozen embryo transfer.

WIDER IMPLICATIONS OF THE FINDINGS

The present study suggests that adolescents conceived by IVF have preserved right ventricular function and aerobic exercise capacity despite a slight alteration in pulmonary vascular distensibility as assessed by two entirely different methods, i.e. exercise echocardiography and lung diffusing capacity measurements. However, the long-term prognostic relevance of this slight decrease in pulmonary vascular distensibility needs to be evaluated in prospective large scale and long-term outcome studies.

STUDY FUNDING/COMPETING INTEREST(S)

Dr Caravita was supported by an ERS PAH short term research training fellowship (STRTF2014-5264). Dr Pezzuto was funded by an Italian Society of cardiology grant. Dr Motoji was supported by a grant from the Cardiac Surgery Funds, Belgium. All authors have no conflicts of interests to declare.

Differential impacts of gonadotrophins, IVF and embryo culture on mouse blastocyst development

RESEARCH QUESTION

Conception via assisted reproductive technology (ART) increases the risk of type 2 diabetes and cardiovascular disease in adulthood. Underlying differences between ART-conceived and in-vivo-conceived embryos that contribute to this increased risk are, however, not known.

DESIGN

This study examined the developmental characteristics of mouse blastocysts derived from ART- compared with in-vivo-conceived embryos. To determine the effect of ovarian stimulation versus IVF versus in-vitro embryo culture on phenotype, six distinct groups of blastocysts were generated. Female mice were naturally cycling or treated with high or mild doses of gonadotrophin, followed by natural mating or IVF under clinical conditions. Embryo morphokinetics were assessed by continuous time-lapse monitoring. Cell lineage allocation to the inner cell mass (Oct4+) or trophectoderm (Cdx2+) was determined by immunohistochemistry, and mitochondrial DNA (mtDNA) copy number was measured by quantitative PCR.

RESULTS

Ovarian stimulation increased embryo number but reduced the percentage of blastocysts. Morphokinetic analysis showed that gonadotrophin treatment led to advanced development (P < 0.05) due to earlier post-pronuclear breakdown. The blastocyst rate was reduced in IVF embryos compared with those fertilized in vivo before culture (P < 0.001). Morphokinetics showed that embryo development was slower in all the IVF groups (P < <0.05), due to a delay from the 3-cell stage. A reduced total and trophectoderm cell number was observed in all groups of cultured blastocysts compared with naturally conceived blastocysts (P < 0.01). Gonadotrophin treatment did not affect the blastocyst mtDNA copy number; however, IVF embryos exhibited reduced mtDNA copy number compared with naturally conceived embryos.

CONCLUSION

Ovarian stimulation, IVF and in-vitro culture differentially impair blastocyst developmental kinetics, differentiation and mtDNA copy number.

Cardiovascular health of 9-year-old IVF offspring: no association with ovarian hyperstimulation and the in vitro procedure

STUDY QUESTION

Are the in vitro procedure, ovarian hyperstimulation or a combination of these two associated with blood pressure (BP) of 9-year-old IVF children born to subfertile couples?

SUMMARY ANSWER

Our study demonstrates that ovarian hyperstimulation and the in vitro procedure are not associated with BP values in 9-year-old children born to subfertile couples.

WHAT IS KNOWN ALREADY

Possible long-term effects of IVF on child health and development have been studied relatively little. This is surprising, as it is known that environmental conditions may influence embryonic and foetal development which may result in health related problems in later life. Some studies suggested that IVF is associated with higher BP at pre-school age. Yet, it is unclear whether this may be also true for older children and if so, which component of IVF, i.e. the ovarian hyperstimulation, the embryo culture or a combination of these, attributes to this potentially less favourable BP.

STUDY DESIGN, SIZE, DURATION

The Groningen Assisted Reproductive Technology cohort-study is a prospective assessor-blinded study of children followed from before birth onwards. In total, 170 children were assessed at the age of 9 years. The attrition rate up until the 9-year-old assessment was 21%.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We evaluated cardiovascular health, focusing on BP (in mmHg and the internationally recognized percentiles of the US National High BP Education Program), heart rate and anthropometrics of 57 children born following controlled ovarian hyperstimulation-IVF/ICSI (COH-IVF/ICSI); 47 children born after modified natural cycle-IVF/ICSI (MNC-IVF/ICSI); and 66 children who were conceived naturally by subfertile couples (Sub-NC). Cardiovascular parameters were measured multiple times on one day. In addition, anthropometric data, including BMI and skinfold thickness, were collected.

MAIN RESULTS AND THE ROLE OF CHANCE

Systolic BP in mmHg did not differ between the COH-IVF/ICSI (mean 106.9, SD 6.7), MNC-IVF/ICSI (mean 104.8, SD 5.9) and Sub-NC (mean 106.3, SD 5.3) groups. In addition, systolic BP percentiles did not differ between the groups: COH-IVF/ICSI (mean 62.4, SD 20.2); MNC-IVF/ICSI (mean 56.3, SD 19.3); and Sub-NC (mean 62.3, SD17.8). Also, after adjustment for confounders BP in the three groups was similar. Heart rate and anthropometric values in the three groups did not differ. For instance, BMI values in the COH-IVF/ICSI-children were 16.3 (median value, range 13.0-24.7), in MNC-IVF/ICSI-children 16.1 (range 12.7-22.5) and in Sub-NC children 16.3 (range 12.7-24.0).

LIMITATIONS, REASONS FOR CAUTION

The size of our study groups does not allow for pertinent conclusions on the effect of ovarian hyperstimulation and the in vitro procedure. The lack of a fertile control group may be regarded as another limitation.

WIDER IMPLICATIONS OF THE FINDINGS

Our study suggests that ovarian hyperstimulation and in vitro procedures are not associated with cardiovascular health in 9-year-old. Yet, BP percentiles of the three groups were higher than the expected 50th percentile. This might indicate that children of subfertile couples have a higher BP than naturally conceived children.

STUDY FUNDING/COMPETING INTEREST(S)

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

Long-term pulmonary vascular consequences of perinatal insults

Development of the pulmonary circulation is a critical component of fetal lung development, and continues throughout infancy and childhood, marking an extended window of susceptibility to vascular maldevelopment and maladaptation. Perinatal vascular insults may result in abnormal vascular structure or function, including decreased angiogenic signaling and vascular endowment, impaired vasoreactivity through increased pulmonary artery endothelial dysfunction and remodeling, or enhanced genetic susceptibility to pulmonary vascular disease through epigenetic modifications or germline mutations. Although some infants develop early onset pulmonary hypertension, due to the unique adaptive capabilities of the immature host many do not have clinically evident early pulmonary vascular dysfunction. These individuals remain at increased risk for development of late-onset pulmonary hypertension, and may be particularly susceptible to secondary insults. This review will address the role of perinatal vascular insults in the development of late pulmonary vascular dysfunction with an effort to highlight areas of critical research need.

Postnatal persistence of fetal cardiovascular remodelling associated with assisted reproductive technologies: a cohort study

OBJECTIVE

To assess the postnatal persistence of fetal cardiovascular remodelling associated with assisted reproductive technologies (ART) in children at 3 years of age.

DESIGN

A cohort study of children conceived by ART.

SETTING

Maternal-Fetal Medicine Unit, Hospital Clinic Barcelona, Spain.

POPULATION SAMPLE

Eighty singleton pregnancies conceived by ART and 80 spontaneously conceived (controls) followed from fetal life up to childhood.

METHODS

Cardiovascular evaluation was performed at 3 years of corrected age, including echocardiography, carotid intima-media (cIMT) by ultrasound, and blood pressure.

MAIN OUTCOME MEASURES

Postnatal persistence of cardiovascular changes in children conceived by ART.

RESULTS

Compared with controls, children conceived by ART showed larger atria (right atrial area: control 4.9 cm² (0.9) versus ART 5.5 cm² (0.9), P < 0.001), more globular ventricles (right ventricular sphericity index: control mean 1.8 (SD 0.5) versus ART 1.6 (0.2), P < 0.001), and signs of systolic (tricuspid annular plane systolic excursion: control 18 mm (2) versus ART 16 mm (3), P < 0.001) and diastolic dysfunction (isovolumic relaxation time: control 68 ms (12) versus ART 79 ms (12), P < 0.001). ART children also presented increased systolic blood pressure (control 90 mmHg (6) versus ART 94 mmHg (5), P < 0.003) and cIMT (control 0.52 μm (0.14) versus ART 0.60 μm (0.16), P < 0.001) as compared with those spontaneously conceived.

CONCLUSIONS

Cardiovascular changes previously reported in ART fetuses persist postnatally at 3 years of age. These results underscore the importance of future studies for assessing the long-term cardiovascular health associated with ART.

TWEETABLE ABSTRACT

Cardiovascular changes described in fetuses conceived by ART, persist in children at 3 years of age.

Metabolic Syndrome and Its Components in Young Adults Conceived by ICSI

BACKGROUND

Intracytoplasmic sperm injection (ICSI) conception presents the early embryo with a radically different environment, which may lead to permanent alterations to key cardiometabolic processes. Blood pressure, indicators of insulin resistance, and lipid profiles have previously been studied in offspring born after in vitro fertilisation (IVF) and ICSI, with conflicting findings. Also, results in young adults born after ICSI are lacking.

AIM

We investigated if young adult men and women conceived by ICSI more frequently have metabolic syndrome and its individual features in comparison to spontaneously conceived controls.

DESIGN

Cardiometabolic and anthropometric parameters from 126 longitudinally followed young adults conceived by ICSI were compared to those of 133 controls.

RESULTS

At age 18 years, only 1 of the participants displayed the metabolic syndrome (1 control woman). Mean concentrations of total cholesterol, triglycerides, insulin, HOMA-IR, and blood pressure were comparable between the ICSI conceived and control participants. A higher proportion (19.6%) of men conceived by ICSI had low (<40 mg/dl) HDL cholesterol compared to controls (5.6%).

CONCLUSIONS

While men conceived by ICSI, but not women, had lower mean HDL cholesterol concentrations in comparison to controls, other markers of the metabolic syndrome were not affected by the mode of conception.

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.

Cardiovascular and metabolic profiles of offspring conceived by assisted reproductive technologies: a systematic review and meta-analysis

OBJECTIVE

To evaluate cardiovascular and metabolic features of offspring conceived by in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI).

DESIGN

Literature review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Offspring from IVF-ICSI versus natural conception.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Systolic and diastolic blood pressure (SBP and DBP), cardiovascular function, body mass index (BMI), and lipid and glucose profiles.

RESULT(S)

We included 19 studies that had recruited 2,112 IVF-ICSI and 4,096 naturally conceived offspring, ranging from childhood to early adulthood. The blood pressure levels of IVF-ICSI offspring were statistically significantly higher than those of naturally conceived offspring (weighted mean differences and confidence intervals: 1.88 mm Hg [95% CI, 0.27, 3.49] for SBP and 1.51 mm Hg [95% CI, 0.33, 2.70] for DBP). In addition, cardiac diastolic function was suboptimal and vessel thickness was higher among IVF-ICSI offspring. Compared with the metabolism of naturally conceived offspring, IVF-ICSI offspring displayed comparable BMI, lower low-density lipoprotein cholesterol levels, and higher fasting insulin levels.

CONCLUSION(S)

Children conceived by IVF-ICSI manifested a minor yet statistically significant increase in blood pressure without the clustering of increased BMI or impaired lipid metabolism by early adulthood. Our findings indicate a risk of cardiovascular disease among IVF-ICSI offspring, which calls for longer-term follow-ups and further investigation.

Maternal age at childbirth is associated with offspring insulin sensitivity: a cross-sectional study in adult male siblings

OBJECTIVE

Maternal age at childbirth is increasing worldwide, but studies investigating the consequences of this trend on offspring metabolic health are scarce. We investigated the associations of maternal age at childbirth with metabolic outcomes in adult male siblings.

METHODS

We used data from 586 men aged 25-45 participating in a cross-sectional, population-based sibling-pair study, including maternal age at childbirth and offspring birthweight, adult weight, height, dual-energy X-ray absorptiometry (DXA)-derived body composition, blood pressure, and total cholesterol, glucose and insulin levels from fasting serum samples. Insulin sensitivity was evaluated using the homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

Maternal age at childbirth was 27·1 ± 4·7 years and was inversely associated with glucose levels (β = -0·10, P = 0·022) and HOMA-IR (β = -0·06, P = 0·065) in age- and body composition-adjusted analyses. Moreover, sons of younger (aged <25 and 25-29) and older (aged ≥35) mothers had higher HOMA-IR values than sons of mothers aged 30-34 (1·39, 1·35 and 1·42 vs 1·19, P = 0·028). Additional adjustment for birthweight did not substantially alter these results. Maternal age was inversely associated with cholesterol levels in unadjusted (β = -0·09, P = 0·032), but not in age- and body composition-adjusted analyses. No associations of maternal age were observed with blood pressure, leptin, or adiponectin levels or with any of the body composition measurements.

CONCLUSIONS

Increasing maternal age at childbirth is associated with lower fasting glucose levels and higher insulin sensitivity in adult male offspring. However, this association might not hold true in offspring of women aged ≥35 years at childbirth.

Can assisted reproductive technologies cause adult-onset disease? Evidence from human and mouse

Millions of children have been born worldwide though assisted reproductive technologies (ART). Consistent with the Developmental Origins of Health and Disease hypothesis, there is concern that ART can induce adverse effects, especially because procedures coincide with epigenetic reprogramming events. Although the majority of studies investigating the effects of ART have focused on perinatal outcomes, more recent studies demonstrate that ART-conceived children may be at increased risk for postnatal effects. Here, we present the current epidemiological evidence that ART-conceived children have detectable differences in blood pressure, body composition, and glucose homeostasis. Similar effects are observed in the ART mouse model, which have no underlying infertility, suggesting that cardiometabolic effects are likely caused by ART procedures and not due to reasons related to infertility. We propose that the mouse system can, consequently, be used to adequately study, modify, and improve outcomes for ART children.

Prevention of vascular dysfunction and arterial hypertension in mice generated by assisted reproductive technologies by addition of melatonin to culture media

Assisted reproductive technologies (ART) induce vascular dysfunction in humans and mice. In mice, ART-induced vascular dysfunction is related to epigenetic alteration of the endothelial nitric oxide synthase (eNOS) gene, resulting in decreased vascular eNOS expression and nitrite/nitrate synthesis. Melatonin is involved in epigenetic regulation, and its administration to sterile women improves the success rate of ART. We hypothesized that addition of melatonin to culture media may prevent ART-induced epigenetic and cardiovascular alterations in mice. We, therefore, assessed mesenteric-artery responses to acetylcholine and arterial blood pressure, together with DNA methylation of the eNOS gene promoter in vascular tissue and nitric oxide plasma concentration in 12-wk-old ART mice generated with and without addition of melatonin to culture media and in control mice. As expected, acetylcholine-induced mesenteric-artery dilation was impaired (P = 0.008 vs. control) and mean arterial blood pressure increased (109.5 ± 3.8 vs. 104.0 ± 4.7 mmHg, P = 0.002, ART vs. control) in ART compared with control mice. These alterations were associated with altered DNA methylation of the eNOS gene promoter (P < 0.001 vs. control) and decreased plasma nitric oxide concentration (10.1 ± 11.1 vs. 29.5 ± 8.0 μM) (P < 0.001 ART vs. control). Addition of melatonin (10(-6) M) to culture media prevented eNOS dysmethylation (P = 0.005, vs. ART + vehicle), normalized nitric oxide plasma concentration (23.1 ± 14.6 μM, P = 0.002 vs. ART + vehicle) and mesentery-artery responsiveness to acetylcholine (P < 0.008 vs. ART + vehicle), and prevented arterial hypertension (104.6 ± 3.4 mmHg, P < 0.003 vs. ART + vehicle). These findings provide proof of principle that modification of culture media prevents ART-induced vascular dysfunction. We speculate that this approach will also allow preventing ART-induced premature atherosclerosis in humans.

Cardiovascular dysfunction in children conceived by assisted reproductive technologies

Epidemiological studies demonstrate a relationship between pathological events during foetal development and future cardiovascular risk and the term 'foetal programming of cardiovascular disease' has been coined to describe this phenomenon. The use of assisted reproductive technologies (ARTs) is growing exponentially and 2-5% of children are now born by this procedure. Emerging evidence indicates that ART represents a novel important example of foetal programming. Assisted reproductive technology may modify the cardiovascular phenotype in two ways: (i) ART involves manipulation of the early embryo which is exquisitely sensitive to environmental insults. In line with this concern, ART alters vascular and cardiac function in children and studies in mice show that ART alters the cardiovascular phenotype by epigenetic alterations related to suboptimal culture conditions. (ii) Assisted reproductive technology markedly increases the risk of foetal insults that augment cardiovascular risk in naturally conceived individuals and are expected to have similar consequences in the ART population. Given the young age of the ART population, it will take another 20-30 years before data on cardiovascular endpoints will be available. What is clear already, however, is that ART emerges as an important cardiovascular risk factor. This insight requires us to revise notions on ART's long-term safety and to engage on a debate on its future. There is an urgent need to better understand the mechanisms underpinning ART-induced alteration of the cardiovascular phenotype, improve the procedure and its long-term safety, and, while awaiting this aim, not to abandon medicine's fundamental principle of doing no harm (to future children) and use ART parsimoniously.