IVF with or without ICSI and the impact on human embryonic brain development: the Rotterdam Periconceptional Cohort

Vitrification affects the post-implantation development of mouse embryos by inducing DNA damage and epigenetic modifications

Vitrification is widely used in assisted reproductive technology (ART) for female infertility, but the long-term effect on the embryo of vitrification has not been comprehensively studied. The study aimed to investigate the effect of vitrification on long-term development of mouse embryos. The warmed embryos which were frozen at 8-cell stage were cultured in vitro until the blastocyst stage and were transferred into recipients. Immunofluorescence staining was performed to evaluate the reactive oxygen species (ROS) level, mitochondrial function, cell apoptosis, DNA damage and histone epigenetic modification in blastocysts. Transmission electron microscopy (TEM) analysis was performed to exam the mitochondrial ultrastructure in blastocysts. The related gene expression and transcriptome profiles were investigated by RT-qPCR and RNA-seq, respectively. Blastocyst and implantation frequencies were not significantly affected by vitrification. However, vitrification significantly reduced blastocyst cell number and the live pup frequency. Vitrification induced ROS accumulation, DNA damage, and apoptosis in mouse blastocysts. The homologous recombination (NHEJ) is the major DNA repair pathway for vitrified embryos. Vitrification elevated H3K4me2/3, H4K12ac, and H4K16ac levels and reduced m6A modification in blastocysts. Moreover, vitrification significantly altered transcriptome profiles of mice placentas and brains at embryonic day 18.5 (E18.5). Thus, vitrification exhibited a long-term effect on mouse embryo viability by increasing ROS levels, DNA damage, altering the epigenetic modifications and transcriptome profiles.

Maternal fatty acid intake and human embryonic growth: the Rotterdam Periconception Cohort

The required intake of macronutrients by women during the periconceptional period for optimal fetal growth is the subject of ongoing investigation. Intake of polyunsaturated fatty acids (PUFA) is positively associated with fetal neural development, growth velocity and birth weight. However, limited evidence indicates that PUFAs play a role in embryogenesis. We aim to investigate the associations between maternal PUFA dietary intake and first trimester embryonic volume (EV) and head volume (HV). In a prospective cohort study (2013-2020), 464 pregnant women at < 8 weeks of gestation were included. Maternal dietary intake of PUFAs, including omega 3 (docosahexaenoic acid, DHA and eicosapentaeonic acid, EPA) and 6, was obtained from food frequency questionnaires, and first trimester three-dimensional ultrasound examinations were performed to measure EV and HV using Virtual Reality techniques. More than 70% of the population had omega 3 intakes below recommendations. A higher intake of PUFAs was associated with a smaller embryonic HV/EV ratio after adjusting for confounders (EPA p = 0.012, DHA p = 0.015, omega 3 and 6 p < 0.001), but no associations were found with EV or HV alone. Omega 3 from fish oil supplements alone was not associated with embryonic growth. Strong adherence to a PUFA-rich dietary pattern was associated with a smaller embryonic HV/EV ratio (DHA and EPA-rich diet p = 0.054, PUFA-rich diet p = 0.002). It is important to increase awareness of the high prevalence of omega 3-deficiency among pregnant women, and the opportunity for prevention by increasing PUFA intake, thereby reducing the risks of adverse pregnancy outcomes which originate during the periconceptional period.

Computational methods for the analysis of early-pregnancy brain ultrasonography: a systematic review

BACKGROUND

Early screening of the brain is becoming routine clinical practice. Currently, this screening is performed by manual measurements and visual analysis, which is time-consuming and prone to errors. Computational methods may support this screening. Hence, the aim of this systematic review is to gain insight into future research directions needed to bring automated early-pregnancy ultrasound analysis of the human brain to clinical practice.

METHODS

We searched PubMed (Medline ALL Ovid), EMBASE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, and Google Scholar, from inception until June 2022. This study is registered in PROSPERO at CRD42020189888. Studies about computational methods for the analysis of human brain ultrasonography acquired before the 20th week of pregnancy were included. The key reported attributes were: level of automation, learning-based or not, the usage of clinical routine data depicting normal and abnormal brain development, public sharing of program source code and data, and analysis of the confounding factors.

FINDINGS

Our search identified 2575 studies, of which 55 were included. 76% used an automatic method, 62% a learning-based method, 45% used clinical routine data and in addition, for 13% the data depicted abnormal development. None of the studies shared publicly the program source code and only two studies shared the data. Finally, 35% did not analyse the influence of confounding factors.

INTERPRETATION

Our review showed an interest in automatic, learning-based methods. To bring these methods to clinical practice we recommend that studies: use routine clinical data depicting both normal and abnormal development, make their dataset and program source code publicly available, and be attentive to the influence of confounding factors. Introduction of automated computational methods for early-pregnancy brain ultrasonography will save valuable time during screening, and ultimately lead to better detection, treatment and prevention of neuro-developmental disorders.

FUNDING

The Erasmus MC Medical Research Advisor Committee (grant number: FB 379283).

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Neurodevelopmental Outcomes of Pregnancies Resulting from Assisted Reproduction: A Review of the Literature

The term infertility is defined as the lack of conception within 1 year of unprotected intercourse. It affects more than 80 million individuals worldwide. It is estimated that 10-15% of couples of reproductive age are challenged by reproductive issues. Assisted reproduction techniques (ART) are responsible for more than 4% of live births. Our aim is to review the research on neurodevelopmental outcomes of newborns born after the implementation of assisted reproduction methods compared to those conceived naturally. We conducted a comprehensive search of the PubMed, Crossref and Google Scholar electronic databases for related articles up to June 2022 using the PRISMA guidelines. Our research revealed a large number of long term follow-up studies between 2 and 18 years of age, with comparable developmental outcomes. Many studies compared the effects of different infertility treatments against natural conception. The review of the literature revealed that ART is safe, as the majority of studies showed no effect on the neurodevelopmental outcomes of the offspring. In most cases when such an effect was observed, it could be attributed to confounding factors such as subfertility, multiple pregnancies and gestational age at delivery. Finally, the increase in the prevalence of neurodevelopmental disorders after ART, as described in studies with statistically significant results, is predominantly marginal, and given the low incidence of neurodevelopmental disorders in the general population, its clinical significance is debatable.

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

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

Maternal One-Carbon Metabolism during the Periconceptional Period and Human Foetal Brain Growth: A Systematic Review

The maternal environment during the periconceptional period influences foetal growth and development, in part, via epigenetic mechanisms moderated by one-carbon metabolic pathways. During embryonic development, one-carbon metabolism is involved in brain development and neural programming. Derangements in one-carbon metabolism increase (i) the short-term risk of embryonic neural tube-related defects and (ii) long-term childhood behaviour, cognition, and autism spectrum disorders. Here we investigate the association between maternal one-carbon metabolism and foetal and neonatal brain growth and development. Database searching resulted in 26 articles eligible for inclusion. Maternal vitamin B6, vitamin B12, homocysteine, and choline were not associated with foetal and/or neonatal head growth. First-trimester maternal plasma folate within the normal range (>17 nmol/L) associated with increased foetal head size and head growth, and high erythrocyte folate (1538-1813 nmol/L) with increased cerebellar growth, whereas folate deficiency (<7 nmol/L) associated with a reduced foetal brain volume. Preconceptional folic acid supplement use and specific dietary patterns (associated with increased B vitamins and low homocysteine) increased foetal head size. Although early pregnancy maternal folate appears to be the most independent predictor of foetal brain growth, there is insufficient data to confirm the link between maternal folate and offspring risks for neurodevelopmental diseases.

Association Between Assisted Reproductive Technology and White Matter Injury in Premature Infants: A Case-Control Study

Objectives: Whether there is a link between assisted reproductive technology (ART) and brain damage in premature infants remains unclear. The aim of this study was to determine whether premature infants conceived by ART are at a greater risk of developing white matter injury (WMI), as detected by magnetic resonance imaging (MRI) or diffusion-weighted imaging (DWI) within 14 days, than those naturally conceived (NC). Methods: A retrospective case-control study was conducted on singleton premature infants with a gestational age of ≥28 weeks and <34 weeks delivered between 2017 and 2019 at Shengjing Hospital, China Medical University. This study included 638 live births that were stratified into case group (n = 218) and control group (n = 420), depending on the presence or absence of WMI. The exposure proportion of ART was compared between the case and control groups, and a logistic regression model was used to identify whether ART was an independent risk factor for WMI. Results: In the univariate analysis, the exposure proportion of ART conception was higher in cases than in controls (12.84 vs. 7.38%, p = 0.024). According to the multivariable analysis, after adjustment for other variables, the association between ART and WMI remained significant (1.82; 95% confidence interval, 1.04-3.21; P = 0.038). Conclusions: Singleton premature infants conceived by ART have a higher risk of WMI than NC infants. Given that ART is an independent risk factor for WMI in premature infants, more attention should be paid to neurodevelopmental outcomes in this group.