The other face of advanced paternal age: a scoping review of its terminological, social, public health, psychological, ethical and regulatory aspects

The effect of parental age on child development at 36 months: Insights from the Japan environment and children's study

BACKGROUND

The impact of parent-childbearing age on child development at 36 months of age is controversial.

AIMS

We used data from a large cohort study with multiple imputation and mediation analyses of variables.

METHODS AND PROCEDURES

A total of 72,606 parent-child pairs from the Japan Environment and Children's Study were included in the study. Parents' ages were categorized into five groups. We used five domains of the Japanese translation of the Ages and Stages Questionnaire, Third Edition (J-ASQ-3). Scores below the cutoff value at 36 months were defined as developmental delays in each domain. We used three logistic analysis models. In Model 3, we analyzed maternal and paternal age using other variables and covariates.

OUTCOMES AND RESULTS

The outcome was a developmental delay in the five domains of J-ASQ-3. In Model 3, ORs for the developmental delay scores regarding parental age were significantly associated with all five domains of J-ASQ-3. The mediation analysis showed a significant mediation interaction effect for mothers but localized for fathers.

CONCLUSION

Advanced paternal and maternal ages were associated with developmental delay in children. Awareness of the risks of childbearing at an advanced age is crucial.

WHAT'S THE PAPER ADDS

This manuscript used data from a large cohort study with multiple imputation and mediation analyses. With these analyses, we identified the pure effect of advanced parental age on their children's development at 36 months.

Against age limits for men in reproductive care

Almost all countries and fertility clinics impose age limits on women who want to become pregnant through Assisted Reproductive Technologies (ART). Age limits for aspiring fathers, however, are much less common and remain a topic of debate. This article departs from the principle of reproductive autonomy and a conditional positive right to receive ART, and asks whether there are convincing arguments to also impose age limits on aspiring fathers. After considering three consequentialist approaches to justifying age limits for aspiring fathers, we take in a concrete normative stance by concluding that those are not strong enough to justify such cut-offs. We reinforce our position by drawing a comparison between the case of a 39-year-old woman who wants to become a single mother via a sperm donor on the one hand, and on the other hand the same woman who wants to have a child with a 64-year-old man who she loves and who is willing to care for the child as long as he is able to. We conclude that, as long as appropriate precautions are taken to protect the welfare of the future child, couples who want to receive fertility treatment should never be limited on the basis of the age of the (male) partner. An absence of age limits for men would respect the reproductive autonomy of both the man and the woman.

Familial factors rather than paternal age contribute to the aetiology of epilepsy

BACKGROUND

Whether paternal age associated with offspring's epilepsy risk is a cause of de novo mutation as men age, or just an association due to confounding factors, is still unclear.

METHODS

We performed a population-based, multi-generation and sibling comparison study in Taiwan, which included 2 751 232 singletons born in 2001-17 who were followed until 2020. Of these, 819 371/826 087 with information on paternal/maternal grandparents were selected for multi-generation analyses and 1 748 382 with sibling(s) were selected for sibling comparison. Cox proportional hazard regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

In the total cohort, there was an increased risk of epilepsy in individuals with advanced paternal age, e.g. the HR for paternal age ≥50 was1.36 (95% CI: 1.15-1.61) compared with paternal age 25-29, and fathers older than mothers, e.g. the HR for parental age difference ≥15 years was 1.29 (95% CI: 1.16-1.43). When accounting for parental age difference, the association between paternal age and epilepsy in offspring was attenuated (HR for paternal age ≥50 was 1.11, 95% CI: 0.93-1.34). Multi-generation analyses did not support the association of advanced grand-paternal age at childbirth of the parent with offspring's risk of epilepsy. Sibling comparison analyses did not support the association of older paternal age with increased risk of epilepsy (HR was 0.96 for per year increase in paternal age, 95% CI: 0.96-0.97).

CONCLUSIONS

These results do not support the hypothesis that advanced paternal age is associated with epilepsy in offspring. Instead, familial factors may explain the observed paternal age association with the offspring's risk of epilepsy.

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

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

KEAP1-NRF2 system regulates age-related spermatogenesis dysfunction

Purpose

The average fatherhood age has been consistently increasing in developed countries. Aging has been identified as a risk factor for male infertility. However, its impact on various mechanisms remains unclear. This study focused on the KEAP1-NRF2 oxidative stress response system, by investigating the relationship between the KEAP1-NRF2 system and age-related changes in spermatogenesis.

Methods

For examination of age-related changes, we used 10-, 30-, 60-, and 90-week-old mice to compare sperm count, sperm motility, and protein expression. For assessment of Keap1 inhibition, 85-week-old C57BL/6J mice were randomly assigned to the following groups: control and bardoxolone methyl (KEAP1 inhibitor). Whole-exome sequencing of a Japanese cohort of patients with non-obstructive azoospermia was performed for evaluating.

Results

Sperm count decreased significantly with aging. Oxidative stress and KEAP1 expression in the testes were elevated. Inhibition of KEAP1 in aging mice significantly increased sperm count compared with that in the control group. In the human study, the frequency of a missense-type SNP (rs181294188) causing changes in NFE2L2 (NRF2) activity was significantly higher in patients with non-obstructive azoospermia than in healthy control group.

Conclusions

The KEAP1-NRF2 system, an oxidative stress response system, is associated with age-related spermatogenesis dysfunction.

A study of the experience of Norwegian IVF physicians in evaluating the parenting capacity of patients

RESEARCH QUESTION

How do Norwegian fertility doctors assess the parenting capacity of applicants, and how do they experience and evaluate the assessment practice?

DESIGN

Qualitative interview study with 14 Norwegian fertility doctors. Interviews were analysed with systematic text condensation, a qualitative analysis framework.

RESULTS

Norwegian fertility doctors deem parenting capacity assessments of applicants to be straightforward and simple in most cases. Yet, some cases of doubt pose difficulties. Physicians can then draw on resources such as colleagues, physicians from other specialties who know the patient and patient records. All the participating physicians agreed with the principle of parenting capacity assessment for patients seeking fertility treatment. The assessment enabled physicians to refuse patients whom they thought should definitely not have responsibility for children. The physicians' main argument was their own felt responsibility for the future child. Even though assessments could be challenging, the participants all thought of themselves as competent to perform them. Indeed, some thought that delegating the assessments would imply abdicating a responsibility that was properly theirs. Although national guidelines might aid decision-making, the physicians would not want guidelines to curtail the significant discretion that they exercised.

CONCLUSIONS

Whether societies should assess applicants' capacity for parenthood before fertility treatment is an ethical and political question. Although sometimes a difficult task, Norwegian fertility doctors see it as important, and as something they are competent and suited to undertake.

Building a family at advanced parental age: a systematic review on the risks and opportunities for parents and their offspring

STUDY QUESTION

What is the existing empirical literature on the psychosocial health and wellbeing of the parents and offspring born at an advanced parental age (APA), defined as 40 years onwards?

SUMMARY ANSWER

Although the studies show discrepancies in defining who is an APA parent and an imbalance in the empirical evidence for offspring, mothers, and fathers, there is a drive towards finding psychotic disorders and (neuro-)developmental disorders among the offspring; overall, the observed advantages and disadvantages are difficult to compare.

WHAT IS KNOWN ALREADY

In many societies, children are born to parents at advanced ages and there is rising attention in the literature towards the consequences of this trend.

STUDY DESIGN SIZE DURATION

The systematic search was conducted in six electronic databases (PubMed including Medline, Embase, Scopus, PsycInfo, CINAHL, and SocINDEX) and was limited to papers published between 2000 and 2021 and to English-language articles. Search terms used across all six electronic databases were: ('advanced parental age' OR 'advanced maternal age' OR 'advanced paternal age' OR 'advanced reproductive age' OR 'late parent*' OR 'late motherhood' OR 'late fatherhood') AND ('IVF' OR 'in vitro fertilization' OR 'in-vitro-fertilization' OR 'fertilization in vitro' OR 'ICSI' OR 'intracytoplasmic sperm injection' OR 'reproductive techn*' OR 'assisted reproductive technolog*' OR 'assisted reproduction' OR 'assisted conception' OR 'reproduction' OR 'conception' OR 'birth*' OR 'pregnan*') AND ('wellbeing' OR 'well-being' OR 'psycho-social' OR 'social' OR 'ethical' OR 'right to reproduce' OR 'justice' OR 'family functioning' OR 'parental competenc*' OR 'ageism' OR 'reproductive autonomy' OR 'outcome' OR 'risk*' OR 'benefit*').

PARTICIPANTS/MATERIALS SETTING METHODS

The included papers were empirical studies in English published between 2000 and 2021, where the study either examined the wellbeing and psychosocial health of parents and/or their children, or focused on parental competences of APA parents or on the functioning of families with APA parents. A quality assessment of the identified studies was performed with the QATSDD tool. Additionally, 20% of studies were double-checked at the data extraction and quality assessment stage to avoid bias. The variables sought were: the geographical location, the year of publication, the methodological approach, the definitions of APA used, what study group was at the centre of the research, what research topic was studied, and what advantages and disadvantages of APA were found.

MAIN RESULTS AND THE ROLE OF CHANCE

A total number of 5403 articles were identified, leading to 2543 articles being included for title and abstract screening after removal of duplicates. This resulted in 98 articles included for a full-text reading by four researchers. Ultimately, 69 studies were included in the final sample. The key results concerned four aspects relevant to the research goals. (i) The studies showed discrepancies in defining who is an APA parent. (ii) There was an imbalance in the empirical evidence produced for different participant groups (mothers, fathers, and offspring), with offspring being the most studied study subjects. (iii) The research topics studied underlined the increased risks of neuro-developmental and psychotic disorders among offspring. (iv) The observed advantages and disadvantages were varied and could not be compared, especially for the offspring of APA parents.

LIMITATIONS REASONS FOR CAUTION

Only English-language studies, published between 2000 and 2021, found in the above-mentioned databases were considered for this review.

WIDER IMPLICATIONS OF THE FINDINGS

More research is necessary to understand the risks and benefits of building a family at an APA for the offspring when they reach adulthood. Furthermore, studies that explore the perspective of older fathers and older parents from non-Western societies would be highly informative.

STUDY FUNDING/COMPETING INTERESTS

The writing of this manuscript was permitted by financial support provided by the Swiss National Science Foundation (Weave/Lead Agency funding program, grant number 10001AL_197415/1, project title 'Family Building at Advanced Parental Age: An Interdisciplinary Approach'). The funder had no role in the drafting of this manuscript and the views expressed therein are those of the authors. The authors have no conflicts of interest.

REGISTRATION NUMBER

This systematic review is registered in Prospero: CRD42022304564.

Expression profiles of circular RNAs in spermatozoa from aging men

BACKGROUND

Advanced paternal age (APA) is associated with decreased fertility, but the mechanism underlying APA remains unknown. CircRNAs have been reported to be ideal candidate biomarkers for diagnostic and therapeutic applications in many diseases and are also involved in spermatogenesis. Hence, we aimed to assess the circRNA expression profile of spermatozoa from aging men.

METHODS AND RESULTS

We recruited 6 subjects, including 3 in the younger group (men age < 40) and 3 in the APA group (men age ≥ 40). RNA sequencing was exploited to identify the expression profiles of circRNAs between the two groups. The expression levels of circRNAs were validated using real-time quantitative polymerase chain reaction (RT-qPCR). Kyoto Encyclopedia of Genes and Genomes biological pathway analysis and Gene Ontology analysis were performed to evaluate the functions of differentially expressed circRNAs (DE-circRNAs) between the two groups. In total, 18,787 circRNAs were sequenced in the spermatozoa of two groups. Our analysis revealed that there were 1056 downregulated circRNAs and 1228 upregulated circRNAs between the two groups, and KEGG analysis showed they were mainly involved in pathways including the DNA repair signaling pathway, meiotic recombination signaling pathway, and PI3K/AKT signaling pathway.

CONCLUSIONS

In conclusion, our study suggested that circRNAs play a vital role in spermatozoa from aging men and provided a fresh perspective on the specific regulatory mechanism of spermatozoa from aging men.

Obstetrical and Perinatal Outcomes Are Not Associated with Advanced Paternal Age in IVF or ICSI Pregnancies with Autologous Oocytes

BACKGROUND

In recent years, there has been an evident delay in childbearing and concerns have been raised about whether this increase in age affects reproductive outcomes. This study aimed to evaluate the effect of paternal age on obstetrical and perinatal outcomes in couples undergoing in vitro fertilization or intracytoplasmic sperm injection using autologous sperm and oocytes.

METHODS

This retrospective study evaluated obstetrical and perinatal outcomes from 14,125 couples that were arbitrarily divided into three groups according to paternal age at conception: ≤30 (n = 1164), 31-40 (n = 11,668) and >40 (n = 1293). Statistics consisted of a descriptive analysis followed by univariate and multivariate models, using the youngest age group as a reference.

RESULTS

The study showed significantly longer pregnancies for the fathers aged 31-40 compared to ≤30 years. However, there were no significant differences for the type of delivery, gestational diabetes, anaemia, hypertension, delivery threat, premature rupture of membranes, preterm birth, very preterm birth, and the neonate's sex, weight, low birth weight, very low birth weight, length, cranial perimeter, Apgar score and neonatal intensive care unit admission.

CONCLUSION

Despite our promising results for older fathers, as paternal age was not associated with clinically relevant obstetrical and perinatal outcomes, future well-designed studies are necessary as it has been associated with other important disorders.

The psychosocial outcomes of older parenthood in early to mid-childhood: a mini-review

Recent decades have seen a global trend towards delaying parenthood, referred to as the 'postponement transition'. Whilst there is plentiful research regarding obstetric and paediatric outcomes related to delayed parenthood, relatively little is known about the psychosocial outcomes associated with advanced parental age during early and middle childhood. This mini-review examines the current literature regarding the psychosocial functioning of families headed by older parents. First, we give an overview of the literature that examines the psychological wellbeing of older first-time parents. We then review the literature regarding the quality of the parent-child relationship in older parent families. Finally, we discuss the psychosocial adjustment and cognitive development of children of older parents. We conclude with suggestions for future research avenues.

Paternal age and 13 psychiatric disorders in the offspring: a population-based cohort study of 7 million children in Taiwan

Although paternal age has been linked to certain psychiatric disorders, the nature of any causal relationship remains elusive. Here, we aimed to comprehensively assess the magnitude of a wide range of offspring's psychiatric risk conferred by paternal age, leveraging a pedigree inferred from covered-insurance relationship (accuracy >98%) in Taiwan's single-payer compulsory insurance program. We also examined whether there is an independent role of paternal age and explored the potential effect of parental age difference. A total cohort of 7,264,788 individuals born between 1980 and 2018 were included; 5,572,232 with sibling(s) were selected for sibling-comparison analyses and 1,368,942 and 1,044,420 children with information of paternal-grandparents and maternal-grandparents, respectively, were selected for multi-generation analyses. Using inpatient/outpatient claims data (1997-2018), we identified schizophrenia, autism, bipolar disorder (BPD), attention deficit-hyperactivity disorder (ADHD), major depressive disorder (MDD), eating disorder (ED), substance use disorder (SUD), mental retardation (MR), tic disorder, obsessive-compulsive disorder (OCD), anxiety, and somatoform disorder. We identified suicides using death certificates. Logistic regression analysis was used to estimate the paternal/maternal/grand-paternal age association with psychiatric risk in the offspring. The total cohort and sibling-comparison cohort resulted in similar estimates. Paternal age had a U-shaped relationship with offspring's MDD, ED, SUD, and anxiety. A very young maternal age (<20 years) was associated with markedly higher risk in offspring's SUD, MR, and suicide. Older paternal age (>25 years) was linearly associated with offspring's schizophrenia, autism, BPD, ADHD, MDD, ED, SUD, MR, OCD, anxiety, and suicide. Older grand-paternal age was linearly associated with offspring's schizophrenia, autism, ADHD, and MR. Dissimilar parental age was positively associated with offspring's ADHD, MDD, SUD, MR, anxiety, and suicide, and negatively associated with offspring's OCD. This comprehensive assessment provides solid evidence for the independent role of paternal age in psychiatric risk in the offspring and clarifies the significance of both early parenthood and delayed paternity.

Age-associated epigenetic changes in mammalian sperm: implications for offspring health and development

BACKGROUND

Modern reproductive behavior in most developed countries is characterized by delayed parenthood. Older gametes are generally less fertile, accumulating and compounding the effects of varied environmental exposures that are modified by lifestyle factors. Clinicians are primarily concerned with advanced maternal age, while the influence of paternal age on fertility, early development and offspring health remains underappreciated. There is a growing trend to use assisted reproductive technologies for couples of advanced reproductive age. Thus, the number of children born from older gametes is increasing.

OBJECTIVE AND RATIONALE

We review studies reporting age-associated epigenetic changes in mammals and humans in sperm, including DNA methylation, histone modifications and non-coding RNAs. The interplay between environment, fertility, ART and age-related epigenetic signatures is explored. We focus on the association of sperm epigenetics on epigenetic and phenotype events in embryos and offspring.

SEARCH METHODS

Peer-reviewed original and review articles over the last two decades were selected using PubMed and the Web of Science for this narrative review. Searches were performed by adopting the two groups of main terms. The first group included 'advanced paternal age', 'paternal age', 'postponed fatherhood', 'late fatherhood', 'old fatherhood' and the second group included 'sperm epigenetics', 'sperm', 'semen', 'epigenetic', 'inheritance', 'DNA methylation', 'chromatin', 'non-coding RNA', 'assisted reproduction', 'epigenetic clock'.

OUTCOMES

Age is a powerful factor in humans and rodent models associated with increased de novo mutations and a modified sperm epigenome. Age affects all known epigenetic mechanisms, including DNA methylation, histone modifications and profiles of small non-coding (snc)RNA. While DNA methylation is the most investigated, there is a controversy about the direction of age-dependent changes in differentially hypo- or hypermethylated regions with advanced age. Successful development of the human sperm epigenetic clock based on cross-sectional data and four different methods for DNA methylation analysis indicates that at least some CpG exhibit a linear relationship between methylation levels and age. Rodent studies show a significant overlap between genes regulated through age-dependent differentially methylated regions and genes targeted by age-dependent sncRNA. Both age-dependent epigenetic mechanisms target gene networks enriched for embryo developmental, neurodevelopmental, growth and metabolic pathways. Thus, age-dependent changes in the sperm epigenome cannot be described as a stochastic accumulation of random epimutations and may be linked with autism spectrum disorders. Chemical and lifestyle exposures and ART techniques may affect the epigenetic aging of sperm. Although most epigenetic modifications are erased in the early mammalian embryo, there is growing evidence that an altered offspring epigenome and phenotype is linked with advanced paternal age due to the father's sperm accumulating epigenetic changes with time. It has been hypothesized that age-induced changes in the sperm epigenome are profound, physiological and dynamic over years, yet stable over days and months, and likely irreversible.

WIDER IMPLICATIONS

This review raises a concern about delayed fatherhood and age-associated changes in the sperm epigenome that may compromise reproductive health of fathers and transfer altered epigenetic information to subsequent generations. Prospective studies using healthy males that consider confounders are recommended. We suggest a broader discussion focused on regulation of the father's age in natural and ART conceptions is needed. The professional community should be informed and should raise awareness in the population and when counseling older men.

Association between paternal age at childbirth and autism spectrum disorder in offspring

OBJECTIVES

To study the association between paternal age at childbirth and the risk of autism spectrum disorder (ASD) in offspring.

METHODS

In this cross-sectional study, 71 children with ASD who were diagnosed in the Department of Child Healthcare in six hospitals in Guangzhou, Foshan, Beijing, Wuhan, Hangzhou, and Chongqing of China from August 2016 to March 2017 were enrolled as subjects, and 284 typically developing children matched for age, sex, and maternal age at childbirth with the ASD children served as controls. A self-design questionnaire was used to collect the data on social demography, maternal pregnancy, and delivery. The association between paternal age at childbirth and the development of ASD in offspring was evaluated by the logistic regression analysis.

RESULTS

After control for demographic factors and pregnancy- and delivery-related factors, the logistic regression analysis showed that a relatively high paternal age at childbirth was significantly associated with the increased risk of ASD in offspring (OR=1.12, 95%CI: 1.02-1.23, P<0.05). After grouping based on the paternal age, the logistic regression analysis showed that paternal age at childbirth of ≥40 years was significantly associated with the risk of ASD in offspring (before adjustment: OR=7.08, 95%CI: 1.77-28.32, P<0.05; after adjustment: OR=8.50, 95%CI: 1.71-42.25, P<0.05).

CONCLUSIONS

High paternal age at childbirth is significantly associated with the increased risk of ASD in offspring, and paternal age at childbirth ≥40 years may be the high-risk age group for ASD in offspring.

Comparison of sperm preparation methods to improve the recovery of mature spermatozoa in sub-fertile males

The integrity of chromatin in the spermatozoon is essential for reproductive outcome. The aim of this study was to evaluate the most effective and cost-effective method to reduce the percentage of spermatozoa with defects in chromatin decondensation for use in assisted reproductive technologies (ART) procedures. Sperm samples from 15 sub-fertile males were examined at CFA Naples to determine the sperm decondensation index (SDI), using the aniline blue test, before and after preparation, comparing density gradients with two different swim-up approaches. All three techniques led to a reduction in decondensed spermatozoa with no statistical difference (P > 0.05) between the control and the treated sperm. In contrast, we found a highly significant decrease in SDI (P < 0.01) after the two swim-up methods in all the samples, confirming the efficacy of these methods in lowering the percentage of chromatin compaction damage. There was no statistical difference between the two swim-up methods, however swim-up from the pellet led to improved count, motility and the percentage of normal condensed spermatozoa. We suggest that swim-up from the pellet be used in ART on sub-fertile males, both to reduce cell stress by multiple centrifugation and improve the recovery rate of mature spermatozoa.

A Federated Blockchain Approach for Fertility Preservation and Assisted Reproduction in Smart Cities

Modern life is making people infertile. Giving birth later in life is wreaking havoc on our fertility and threatening human survival. Smart cities intend to optimize the quality of life of their citizens by utilizing technology for smarter living. This research first identifies the requirements and business opportunities of using advanced technology for smarter fertility preservation and assisted reproduction in smart cities. A federated blockchain approach is proposed for the alliance of integrated commercial egg banks (ICEBs). In particular, we designed a membership fee rebate (MFR) mechanism that offers incentives for blockchain creations in the egg banking alliance. We formulated the MFR problem into a leader–followers Stackelberg game whose objectives are (1) to maximize the benefits of forming the alliance (the leader) and (2) to maximize the benefits in each ICEB (the follower). We developed an iterative scheme that utilizes mathematical programming techniques to solve the two-level, Stackelberg game problem. With a given set of parameters of the alliance and membership fee function, and the average number of blocks generated for an oocyte, the iterative scheme achieves the optimal solution for the MFR rate per block created. A numerical example demonstrates the feasibility and applicability of the proposed iterative scheme. Numerical results show that it achieves good solutions in adding a small to medium-sized new ICEB to the existing alliance. The proposed federated approach lays the foundation for developing a blockchain-based egg banking platform.

Lower female partner live birth rate in male cancer survivors: An age-matched cohort analysis of the Utah Population Database

We determine the time to first live birth for female partners of males after a cancer diagnosis. Our group performed a retrospective, population-based, age-matched cohort study of Utah male residents diagnosed with cancer at age 18 years or later between 1956 and 2013 (exposed) matched to male Utah residents without cancer diagnosis (unexposed). Using stratified Cox proportional hazard models, we adjusted for race, ethnicity and number of live births prior to cancer diagnosis, to estimate the effect of time to a partner live birth following cancer diagnosis. Our study cohort included 19,303 men diagnosed with cancer (exposed) and 93,608 age-matched men without cancer diagnoses (unexposed). Exposed men were less likely to have a live birth prior to first cancer diagnosis (60.7% vs. 65.4%, p < 0.001) and after first cancer diagnosis (10.9% vs. 12.2%, p < 0.001) compared to unexposed men. Exposed men had a fertility hazard rate that was 31% lower after cancer diagnosis date than unexposed men (HR: 0.69; 95% CI: 0.65-0.72). This was most profound for men aged 18-30 years (HR: 0.59, 95% CI: 0.55-0.63). Male cancer survivors have a 31% lower female partner live birth rate after cancer diagnosis. These findings are important for patient counselling regarding fertility preservation at the time of cancer diagnosis.

Development of thalamus mediates paternal age effect on offspring reading: A preliminary investigation

The importance of (inherited) genetic impact in reading development is well established. De novo mutation is another important contributor that is recently gathering interest as a major liability of neurodevelopmental disorders, but has been neglected in reading research to date. Paternal age at childbirth (PatAGE) is known as the most prominent risk factor for de novo mutation, which has been repeatedly shown by molecular genetic studies. As one of the first efforts, we performed a preliminary investigation of the relationship between PatAGE, offspring's reading, and brain structure in a longitudinal neuroimaging study following 51 children from kindergarten through third grade. The results showed that greater PatAGE was significantly associated with worse reading, explaining an additional 9.5% of the variance after controlling for a number of confounds-including familial factors and cognitive-linguistic reading precursors. Moreover, this effect was mediated by volumetric maturation of the left posterior thalamus from ages 5 to 8. Complementary analyses indicated the PatAGE-related thalamic region was most likely located in the pulvinar nuclei and related to the dorsal attention network by using brain atlases, public datasets, and offspring's diffusion imaging data. Altogether, these findings provide novel insights into neurocognitive mechanisms underlying the PatAGE effect on reading acquisition during its earliest phase and suggest promising areas of future research.