2D:4D ratio in children at familial high-risk for eating disorders: The role of prenatal testosterone exposure

Assessing body composition through anthropometry: Implications for diagnosing and managing polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a multifaceted endocrine disorder with profound implications for the reproductive and metabolic health of women. The utilization of anthropometric measures in the diagnosis and management of PCOS has gained increasing attention due to their practicality and predictive capacity for associated conditions such as obesity and insulin resistance. This review rigorously explores the application of various anthropometric indices, including body mass index, waist-to-hip ratio, and advanced metrics such as the body shape index and body roundness index, wrist circumference, neck circumference. These indices offer critical insights into body fat distribution and its association with the metabolic and hormonal perturbations characteristic of PCOS. The review underscores the necessity of addressing obesity, a prevalent comorbidity in PCOS, through lifestyle modifications and personalized therapeutic approaches. By incorporating anthropometric evaluations into routine clinical practice, healthcare professionals can enhance diagnostic precision, optimize treatment strategies, and ultimately improve patient outcomes. This integrative approach not only facilitates the management of the metabolic challenges inherent in PCOS but also contributes to the development of more individualized therapeutic interventions, thereby enhancing the overall quality of life for women affected by PCOS.

Maternal sex-hormone exposure and the risk of eating disorders in daughters

Potential effects of prenatal sex hormones on later eating disorders in offspring have been investigated with two indirect methods (finger length ratio, opposite- versus same-sex twins). We utilized a direct, prospective method, examining the association between prenatal sex-hormones in maternal sera and the risk of bulimia nervosa (BN) and anorexia nervosa (AN) among daughters. Females with BN (55), AN (150), sister controls without eating disorders (one per case), and population controls (one per case) were derived from Finnish registers. Maternal gestational testosterone and estradiol levels were assayed from archived specimens stored in a national serum biobank. When females with BN were compared to their sister controls, those with higher gestational testosterone levels were at an increased risk of BN. No significant associations with BN were found when the comparison was made to population controls, and when estradiol levels and testosterone/estrogen ratio were assessed. We neither found associations between gestational sex-hormone levels and the risk of AN. Among females with familial liability for BN, higher gestational testosterone exposure may have a role in later development of BN, whereas lower testosterone exposure may have a protective effect. We found no evidence for the involvement of gestational sex-hormones in the etiology of AN.

Prevalence and Etiology of Eating Disorders in Polycystic Ovary Syndrome: A Scoping Review

Polycystic ovary syndrome (PCOS) is the most common endocrine-metabolic disorder affecting females across the lifespan. Eating disorders (EDs) are psychiatric conditions that may impact the development of PCOS and comorbidities including obesity, metabolic syndrome, and type 2 diabetes. The aim of this scoping review was to determine the prevalence of EDs and disordered eating, and to review the etiology of EDs in PCOS. The review was conducted using search terms addressing PCOS, EDs, and disordered eating in databases, including PubMed, Scopus, PsycINFO, and CINAHL. Structured interviews, self-administered questionnaires, chart review, or self-reported diagnosis were used to identify EDs in 38 studies included in the review. The prevalence of any ED in those with PCOS ranged from 0% to 62%. Those with PCOS were 3-6-fold more likely to have an ED and higher odds ratios (ORs) of an elevated ED score compared with controls. In those with PCOS, 30% had a higher OR of bulimia nervosa and binge ED was 3-fold higher compared with controls. Studies were limited on anorexia nervosa and other specified feeding or ED (such as night eating syndrome) and these were not reported to be higher in PCOS. To our knowledge, no studies reported on avoidant/restrictive food intake disorder, rumination disorder, or pica in PCOS. Studies showed strong associations between overweight, body dissatisfaction, and disordered eating in PCOS. The etiologic development of EDs in PCOS remains unclear; however, psychological, metabolic, hypothalamic, and genetic factors are implicated. The prevalence of any ED in PCOS varied because of the use of different diagnostic and screening tools. Screening of all individuals with PCOS for EDs is recommended and high-quality studies on the prevalence, pathogenesis of specific EDs, relationship to comorbidities, and effective interventions to treat ED in those with PCOS are needed.

Risk factors for eating disorders: findings from a rapid review

BACKGROUND

Risk factors represent a range of complex variables associated with the onset, development, and course of eating disorders. Understanding these risk factors is vital for the refinement of aetiological models, which may inform the development of targeted, evidence-based prevention, early intervention, and treatment programs. This Rapid Review aimed to identify and summarise research studies conducted within the last 12 years, focusing on risk factors associated with eating disorders.

METHODS

The current review forms part of a series of Rapid Reviews to be published in a special issue in the Journal of Eating Disorders, funded by the Australian Government to inform the development of the National Eating Disorder Research and Translation Strategy 2021-2031. Three databases were searched for studies published between 2009 and 2021, published in English, and comprising high-level evidence studies (meta-analyses, systematic reviews, moderately sized randomised controlled studies, moderately sized controlled-cohort studies, or population studies). Data pertaining to risk factors for eating disorders were synthesised and outlined in the current paper.

RESULTS

A total of 284 studies were included. The findings were divided into nine main categories: (1) genetics, (2) gastrointestinal microbiota and autoimmune reactions, (3) childhood and early adolescent exposures, (4) personality traits and comorbid mental health conditions, (5) gender, (6) socio-economic status, (7) ethnic minority, (8) body image and social influence, and (9) elite sports. A substantial amount of research exists supporting the role of inherited genetic risk in the development of eating disorders, with biological risk factors, such as the role of gut microbiota in dysregulation of appetite, an area of emerging evidence. Abuse, trauma and childhood obesity are strongly linked to eating disorders, however less conclusive evidence exists regarding developmental factors such as role of in-utero exposure to hormones. Comorbidities between eating disorders and mental health disorders, including personality and mood disorders, have been found to increase the severity of eating disorder symptomatology. Higher education attainment, body image-related factors, and use of appearance-focused social media are also associated with increased risk of eating disorder symptoms.

CONCLUSION

Eating disorders are associated with multiple risk factors. An extensive amount of research has been conducted in the field; however, further studies are required to assess the causal nature of the risk factors identified in the current review. This will assist in understanding the sequelae of eating disorder development and in turn allow for enhancement of existing interventions and ultimately improved outcomes for individuals.

A systematic review and meta-analysis of the association between maternal polycystic ovary syndrome and neuropsychiatric disorders in children

There is emerging evidence demonstrating an association between maternal polycystic ovary syndrome (PCOS) and autism spectrum disorder (ASD) in children, however, the cumulative effect of maternal PCOS on the development of ASD or other neuropsychiatry disorders (NPD) in children and separately for males and females has not been examined. We sought to systematically evaluate the influence of maternal PCOS on a wide range of NPD including ASD, attention deficit hyperactivity disorder (ADHD), chronic tic disorder (CDT), other behavior disorders, anxiety, depression, bipolar disorder, schizophrenia in children as well as in women of reproductive age only. We queried electronic databases including PubMed, EMBASE, and Google Scholar, until March 2021. We used DerSimonian and Laird (D-L) random effects method to compute pooled effect size in terms of odds ratio (OR). Nineteen studies (1667851 mothers, 2260622 children) were included in this study. Mothers with PCOS had an increased odds of children diagnosed with ASD (OR = 1.40, p < 0.001), ADHD (OR = 1.42, p < 0.001), CTD (OR = 1.44, p = 0.001), anxiety (OR = 1.33, p < 0.001), as well as other behavioral symptoms (OR = 1.45, p < 0.001) in the adjusted analysis. The association between maternal PCOS and ASD (OR: 1.43 vs. 1.66), ADHD (OR: 1.39 vs. 1.54), and CTD (OR: 1.42 vs. 1.51) was found to be significantly consistent between males and females, respectively. Our data do not suggest increased fetal testosterone exposure is associated with increased autistic traits in children. However, PCOS was significantly associated with increased odds of a wide range of NPD in women themselves. Maternal PCOS is a risk factor for various NPD with a similar extent in their children regardless of their underlying comorbidities. Managing PCOS is essential for women's health as well as for their children's health. More research is needed to determine the mechanisms and links between maternal PCOS and NPD in children.

Gonadal Hormone Influences on Sex Differences in Binge Eating Across Development

PURPOSE OF REVIEW

Binge eating is a transdiagnostic symptom that disproportionately affects females. Sexually dimorphic gonadal hormones (e.g., estradiol, testosterone) substantially impact eating behavior and may contribute to sex differences in binge eating. We examine recent evidence for the role of gonadal hormones in binge eating risk across development.

RECENT FINDINGS

Both organizational (long-lasting impact on the central nervous system (CNS)) and activational (transient influences on the CNS) hormone effects may contribute to sex differences in binge eating. Gonadal hormones also impact within-sex variability in binge eating, with higher estradiol levels in females and higher testosterone levels in males protective across development. Emerging evidence suggests that the impact of gonadal hormones may be greatest for people with other risk factors, including genetic, temperamental (e.g., high negative affect), and psychosocial (e.g., exposure to weight-based teasing) risk. Gonadal hormones contribute to sex differences and within-sex variability in binge eating across development.

Evaluation of 2D:4D digit ratio in bipolar 1 disorder patients and its relationship with treatment response

BACKGROUND

The role of sex steroids in bipolar disorder (BD) has been demonstrated in adults. We aimed to evaluate the 2D:4D ratio, which indirectly reflects prenatal sex steroids, in BD. Another purpose of this study was to determine the relationship between clinical features, especially lithium response, and digit ratio.

METHODS

The study included 74 patients with bipolar 1 disorder and 74 healthy individuals matched according to age, gender, and educational status. The digit ratio was calculated by dividing the index finger (2D) length by the ring finger (4D) length in both hands. A lithium response scale was used to evaluate the lithium response history.

RESULTS

There was no difference in 2D:4D ratio between the patients and controls in either right or left hands. The digit ratio was not different between groups with and without suicide attempts. The 2D:4D ratio in the patient group was lower in individuals unresponsive to lithium therapy than in partial and good responders for both right and left hands.

DISCUSSION

According to the results of our study, the 2D:4D ratio in the BD group was not different from healthy controls but was lower in patients unresponsive to lithium. In this respect, the 2D:4D ratio can be considered as a biomarker for lithium response in BD. In large-sample studies, the 2D:4D ratio should be investigated for pathophysiology and treatment response of BD.

Gonadal hormone contributions to individual differences in eating disorder risk

PURPOSE OF REVIEW

Females experience eating disorders at substantially higher rates than males. Although sociocultural factors have traditionally been thought to underlie this sex disparity, accumulating evidence implicates differential exposure to gonadal hormones early in life. Gonadal hormones also impact within-sex variability in disordered eating, helping to explain why not all women develop an eating disorder, and some men do. We review recent findings regarding these gonadal hormone effects and their implications for the etiology of eating disorders.

RECENT FINDINGS

Males are exposed to significantly higher testosterone levels than females perinatally, and this exposure appears to protect against later binge eating in males relative to females. Within-sex, higher estradiol levels among females and higher testosterone levels among males appear to be protective. Progesterone exhibits minimal direct phenotypic effects on disordered eating but appears to counteract the protective effects of estrogen in adult females. Importantly, gonadal hormone effects may be moderated by psychosocial factors.

SUMMARY

Evidence suggests that gonadal hormones play a critical role in the etiology of disordered eating. Overall, higher testosterone and estrogen appear to be protective across development. Additional research is needed to identify mechanisms underlying these effects and further explore interactions between hormonal and psychosocial risk.

Neuroendocrinology of reward in anorexia nervosa and bulimia nervosa: Beyond leptin and ghrelin

The pathophysiology of anorexia nervosa (AN) and bulimia nervosa (BN) are still poorly understood, but psychobiological models have proposed a key role for disturbances in the neuroendocrines that signal hunger and satiety and maintain energy homeostasis. Mounting evidence suggests that many neuroendocrines involved in the regulation of homeostasis and body weight also play integral roles in food reward valuation and learning via their interactions with the mesolimbic dopamine system. Neuroimaging data have associated altered brain reward responses in this system with the dietary restriction and binge eating and purging characteristic of AN and BN. Thus, neuroendocrine dysfunction may contribute to or perpetuate eating disorder symptoms via effects on reward circuitry. This narrative review focuses on reward-related neuroendocrines that are altered in eating disorder populations, including peptide YY, insulin, stress and gonadal hormones, and orexins. We provide an overview of the animal and human literature implicating these neuroendocrines in dopaminergic reward processes and discuss their potential relevance to eating disorder symptomatology and treatment.

[Genetics factors in pathogenesis and clinical genetics of binge eating disorder]

Genetic studies have shown that binge eating disorder (ВЕD) aggregates in families, heritability was estimated as about 60% and additive genetic influences on BED up to 50%. Using a genetic approach has proved useful for verifying the diagnostic categories of BED using DSM-IV criteria and supporting the validity of considering this pathology as a separate nosological category. The results confirmed the genetic and pathogenic originality of BED as a separate psychopathological phenomenon, but not a subtype of obesity. It seems fruitful to considerate BED as a disease with hereditary predisposition with significant genetic influence and a complex psychopathological syndrome, including not only eating disorders, but also depressive and addictive component. A possible mechanism of pathogenesis of BED may be the interaction of the neuroendocrine and neurotransmitters systems including the active involvement of the reward system in response to a variety of chronic stress influences with the important modulatory role of specific personality traits. The high level of genetic influence on the certain clinical manifestations of BED confirms the ability to identify the subphenotypes of BED on genetic basis involving clinical criteria. It can not only contribute to further genetic studies, taking into account more homogeneous samples, but also help in finding differentiated therapeutic approaches.

Anorexia Nervosa, Theory and Treatment: Where Are We 35 Years on from Hilde Bruch's Foundation Lecture?

Hilde Bruch's foundation lecture in 1982 is a milestone from which to survey current theory and treatment for anorexia nervosa. Bruch described problems in body perception, emotion processing and interpersonal relationships as core theoretical aspects of the illness and built her theory of psychopathology on these aspects, as well as on animal studies on attachment. She also noted that many psychological problems result as consequence of starvation. In the first part of this paper, we parse Bruch's clinical descriptions into elements of psychopathology (disturbances in body perception, attachment, emotion expression, perception and regulation, social comparison, interpersonal, and family and therapeutic relationships), in order to assemble and update the theoretical evidence for a model of the illness. In the second part, we describe and extend her description of three core targets of treatment: family relationships, patient's inner confusion and nutritional restoration. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

Preliminary evidence that digit length ratio (2D:4D) predicts neural response to delivery of motivational stimuli

Reduced relative length of the 2nd to 4th digits (2D:4D) is thought to partially reflect fetal testosterone (FT) exposure, a process suspected to promote relatively permanent effects on the brain and behavior via structural and functional neuroadaptations. We examined the effect of 2D:4D on neural response - assessed by P2a and feedback-related negativity (FRN) event-related potentials (ERPs) - to motivational stimuli (reward or punishment) using two counterbalanced conditions of a passive S1/S2 outcome prediction design. P2a to expected and unexpected delivered rewards or punishments ($1 or white noise burst, respectively) and FRN to withheld rewards or punishments ($0 or silence, respectively) were observed in undergraduates. Lower left 2D:4D and greater 2D:4D_R-L predicted amplified P2a to the delivery (but not FRN to the omission) of motivationally salient stimuli, regardless of valence and probability. These preliminary findings suggest that FT may organize dopamine neurons to respond more strongly to the delivery of motivational stimuli.

Sex Differences in Binge Eating: Gonadal Hormone Effects Across Development

Eating disorders are highly sexually differentiated disorders that exhibit a female predominance in risk. Most theories focus on psychosocial explanations to the exclusion of biological/genetic influences. The purpose of this descriptive review is to evaluate evidence from animal and human studies in support of gonadal hormone effects on sex differences in binge eating. Although research is in its nascent stages, findings suggest that increased prenatal testosterone exposure in males appears to protect against binge eating. Although pubertal testosterone may exert additional protective effects, the prenatal period is likely critical for the decreased risk observed in males. By contrast, studies indicate that, in females, it is the lack of prenatal testosterone coupled with the organizational effects of pubertal ovarian hormones that may lead to increased binge eating. Finally, twin data suggest that changes in genetic risk may underlie these hormone influences on sex differences across development.

Obstetric and gynecologic problems associated with eating disorders

OBJECTIVE

This article summarizes the literature on obstetric and gynecologic complications associated with eating disorders.

METHOD

We performed a comprehensive search of the current literature on obstetric and gynecologic complications associated with eating disorders using PubMed. More recent randomized-controlled trials and larger data sets received priority. We also chose those that we felt would be the most relevant to providers.

RESULTS

Common obstetric and gynecologic complications for women with eating disorders include infertility, unplanned pregnancy, miscarriage, poor nutrition during pregnancy, having a baby with small head circumference, postpartum depression and anxiety, sexual dysfunction and complications in the treatment for gynecologic cancers. There are also unique associations by eating disorder diagnosis, such as earlier cessation of breastfeeding in anorexia nervosa; increased polycystic ovarian syndrome in bulimia nervosa; and complications of obesity as a result of binge eating disorder.

DISCUSSION

We focus on possible biological and psychosocial factors underpinning risk for poor obstetric and gynecological outcomes in eating disorders. Understanding these factors may improve both our understanding of the reproductive needs of women with eating disorders and their medical outcomes. We also highlight the importance of building multidisciplinary teams to provide comprehensive care to women with eating disorders during the reproductive years.

Digit ratio and autism spectrum disorders in the Avon Longitudinal Study of Parents and Children: a birth cohort study

OBJECTIVES

To investigate whether second-to-fourth digit ratio (2D:4D), a measure commonly used as a proxy for fetal testosterone exposure, is associated with autism spectrum disorders (ASDs), as predicted by the extreme male brain theory of autism.

DESIGN

A birth cohort study.

SETTING

The Avon Longitudinal Study of Parents and Children (ALSPAC).

PARTICIPANTS

6015 ALSPAC children with data on digit ratio, at least 1 outcome measure and information on potential confounding variables (parental occupational class, maternal education and age at digit ratio measurement). Digit ratio was measured by the photocopy and calliper method.

OUTCOMES

ASD diagnosis (cases were identified previously by record linkage or maternal report) and 4 measures that combine optimally within ALSPAC to predict ASD: the Children's Communication Checklist (coherence subscale), the Social and Communication Disorders Checklist, a repetitive behaviour measure, and the Emotionality, Activity and Sociability scale (sociability subscale). These measures were dichotomised, with approximately 10% defined as the 'risk' group.

RESULTS

Using logistic regression, we examined the association of 2D:4D with ASDs and 4 dichotomised ASD traits. Covariates were occupational class, maternal education and age at 2D:4D measurement. 2D:4D was not associated with ASDs in males (adjusted OR per 1 SD increase in mean 2D:4D, 0.88 (95% CI 0.65 to 1.21), p=0.435) or females (adjusted OR=1.36 (95% CI 0.81 to 2.28), p=0.245). Similar results were observed after adjustment for IQ. There was 1 weak association between reduced coherence and increased left 2D:4D in males, in the opposite direction to that predicted by the extreme male brain theory (adjusted OR=1.15 (95% CI 1.02 to 1.29), p=0.023). Given multiple comparisons, this is consistent with chance.

CONCLUSIONS

In this population-based study, there was no strong evidence of an association between 2D:4D and ASD diagnosis or traits, although the CIs were wide. These results are not consistent with the extreme male brain theory.

Social cognition in children at familial high-risk of developing an eating disorder

Objective: Diagnosis of an eating disorder (ED) has been associated with differences in social cognition. To date research investigating social cognition and ED has mainly employed patient and recovered samples. It is therefore unclear whether differences in social cognition are present prior to onset of ED, potentially contributing to development, or whether differences observed are a consequence of the disorder. We aimed to further explore whether individuals at high-risk for ED present social cognition characteristics previously found in ED groups.

Methods: Our sample was drawn from a population-based cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC). Data on maternal ED behaviors over the lifetime were collected through in-depth clinical interviews (n = 1128) conducted using the Structured Clinical Interview for DSM disorders (SCID), and were used to categorize mothers according to ED behaviors over the lifetime: Restricting and Excessive Exercising (n = 58), Purging (n = 70), Binge-eating (n = 72), Binging and Purging (n = 66), no ED (n = 862). High-risk status of children was determined using these maternal lifetime behavioral phenotypes. Children at high-risk (maternal ED exposure) were compared to children at low-risk (born to mothers with no ED) on three measures of social cognition: the Social Communication Disorders Checklist (SCDC) (n = 922), the faces subtest of the Diagnostic Analysis of Non-Verbal Accuracy (DANVA) (n = 722), and the Emotional Triangles Task (n = 750).

Results: Children at high-risk for ED showed poorer performance on measures of social cognition compared to children at low-risk. Maternal lifetime binge-eating, and maternal lifetime binging and purging were associated with poorer social communication in children (OR: 2.4, 95% CI: 1.0, 5.7, p = 0.05; and OR: 2.7, 95% CI: 1.1, 6.5, p = 0.03 respectively). Maternal binging and purging was also found to be associated with differential facial emotion processing and poorer recognition of fear from social motion cues (B: −0.7, 95% CI: −1.1, −0.2, p = 0.004).

Discussion: Children at high-risk for ED showed slight differences in some areas of social cognition when compared to children at low-risk. Characteristic patterns in social cognition are present in children at high-risk for ED, particularly among children whose mothers have binge-eating and purging behaviors over the lifetime. Our findings support the hypothesis that these differences may be part of an intermediate phenotype for ED: perhaps contributing to development, or perhaps indexing a shared liability with psychiatric disorders characterized by abnormal social cognition.

Prenatal and perinatal factors in eating disorders: a descriptive review

OBJECTIVE

The objective of this descriptive review is to summarize the current scientific evidence on various prenatal and perinatal exposures affecting later development of eating disorders among offspring.

METHOD

Studies were searched from PubMed database with the following keywords: eating disorders and disordered eating and anorexia nervosa and bulimia nervosa and binge eating disorder and prenatal exposure delayed effects and maternal exposure and perinatology. A comprehensive manual search, including search from the reference list of included articles, was also performed.

RESULTS

The attributable risk for prenatal and perinatal factors in anorexia nervosa (AN) is 3.6%. Numerous prenatal and perinatal factors have been associated with offspring AN, but only prematurity has been replicated in different samples. The risk of bulimia nervosa (BN) in offspring has attracted less study, and despite varying positive associations, there are no replicated findings. Higher prenatal testosterone may protect against the development of a range of disordered eating symptoms, although studies are not consistent.

DISCUSSION

Evidence in support of an effect of prenatal and perinatal factors on eating disorders or disordered eating in offspring is conflicting. If present, the overall effect appears to be relatively small, and it is likely that the early risk factors operate in conjunction with other biological, genetic, and/or environmental risk factors to bring on eating pathology. Genetically sensitive designs, such as sibling and twin studies, are needed to disentangle the different types of risk factors and ensure that prenatal/perinatal effects are "causal" rather than indications of genetic risk.

Second to fourth digit ratio is a predictor of sporting ability in elite Indian male kabaddi players

BACKGROUND

To determine the 2D:4D ratio in elite Indian male kabaddi players and compare them with non-athletes.

OBJECTIVES

Our study was undertaken to find out a possible relation between digit ratio and sporting ability of male kabaddi players. This study also gives an insight into the possible ethnic differences between Indian sports personnel and other populations.

PATIENTS AND METHODS

Both right and left hands of 33 male kabaddi players attending training camp at the Bangalore regional centre of Sports Authority of India were scanned. Lengths of second and fourth digits were measured and their ratio calculated. Age, weight, height and body mass index matched subjects (25 males) who did not participate in any sports formed the control group.

RESULTS

A highly significant difference was found in 2D:4D ratios of both the hands with Kabaddi players having a lower ratio compared to their controls. There was no statistically significant difference in 2D:4D (Δ r-l) between Kabaddi players and controls.

CONCLUSIONS

Kabaddi is an intermediate sport not requiring a high level of endurance but at the same time requires masculine traits because of combating nature of the game. 2D:4D ratios can be used as reliable additional criteria when screening for prospective players to be inducted into the team.

Prenatal testosterone of progenitors could be involved in the etiology of both anorexia nervosa and autism spectrum disorders of their offspring

OBJECTIVES

High intrauterine testosterone (T) levels seem to play a role in the development of autism spectrum disorders (ASDs), but their role in anorexia nervosa (AN) is controversial. Parents with masculinized 2D:4D ratios, a marker of the organizational effects of T, may have other relevant biological characteristics, in particular exposing their offspring to high T levels in the prenatal environment. This would increase the likelihood of their offspring developing these disorders.

METHODS

The present study examined whether parents of offspring with AN (n=34; mean age= 51) and ASD (n=36; mean age=45) differ from control parents (n=40; mean age=43) in 2D:4D ratio, as well as by salivary T levels and its relationships.

RESULTS

Our results revealed that AN and ASD parents (fathers and mothers) have masculinized 2D:4D ratios of the right hand compared to control parents. However, the difference compared to controls was larger in the ASD than the AN group. Furthermore, current salivary T levels were negatively related to the 2D:4D ratio in ASD and AN parents only.

CONCLUSIONS

Our data partially support the view of high prenatal masculinization as a potential intermediate phenotype to the development of these disorders in their offspring.