Is exposure to high levels of maternal intrauterine testosterone a causal factor common to male sex, autism, gender dysphoria, and non-right-handedness?

Transidentities and autism spectrum disorder: A systematic review

Transidentity and autism frequently co-occur. Previous reviews have focused mainly on frequencies. Here, we conducted a systematic review to condense all the studies and themes on this co-occurrence and to offer a global view. We followed the PRISMA method and selected 77 articles (including 59 clinical studies) in April 2022. We found 5 main themes (sex ratio, theories, sexual orientation, clinical and social consequences, and care implications) in addition to frequencies. Many theories have been proposed to explain the co-occurrence. One posits that social difficulties related to autism would lead to less identification with gender norms and less pressure to conform to these norms, allowing for greater gender diversity in people with autism. Given their difficulties with social interactions and communication, the announcement of one's transidentity to one's social group is often discredited, increasing the risk of suffering and delayed care. Many reports reaffirm the importance of providing specialised care for transgender people with autism. Autism is not a contraindication for gender-affirming treatment. However, some cognitive specificities can affect the planning of care, and transgender people with autism are at high risk of discrimination and harassment. We conclude that there is a need to raise awareness about gender and autism.

Prenatal Androgen Exposure and Traits of Autism Spectrum Disorder in the Offspring: Odense Child Cohort

Fetal androgen exposure may be associated with autism spectrum disorder (ASD). We studied 1777 mother-child pairs in the prospective Odense Child Cohort. Prenatal androgen exposure was assessed by maternal 3rd trimester testosterone concentrations, maternal polycystic ovary syndrome (PCOS), and 3 months offspring anogenital distance. ASD traits were assessed at age 3 years with the ASD-symptom scale of the Child Behavior Checklist for ages 1½-5 years. Maternal testosterone was positively associated with traits of ASD in boys (p < 0.05). Maternal PCOS was associated with increased offspring ASD traits (p = 0.046), but became non-significant after excluding parental psychiatric diagnosis. Offspring anogenital distance was not linked to ASD traits. Higher prevalence of ASD in boys could be linked to higher susceptibility to fetal androgen exposure.

Tetramethyl bisphenol A stimulates proliferation but inhibits fetal Leydig cell function in male rats by targeting estrogen receptor α after in utero exposure

Tetramethyl bisphenol A (TMBPA) is a widely used flame retardant. TMBPA has been a toxic to Leydig cells in puberty, but it remains unclear whether TMBPA has a similar inhibitor effect on fetal Leydig cells (FLCs). This study reported morphological and functional alterations of FLCs in the testes of male offspring at birth after in utero exposure to TMBPA. Pregnant Sprague Dawley rats were dosed via continuous gavage of TMBPA (0, 10, 50, and 200 mg/kg/day) from gestational day 14 to 21. TMBPA markedly raised serum total testosterone level, testicular volume, and FLC number of male offspring at 200 mg/kg dose. The up-regulation of Insl3, Star, and Cyp11a1 mRNAs was observed after 200 mg/kg TMBPA exposure. After normalization to the number of FLCs, TMBPA significantly reduced Lhcgr and Hsd3b1 expressions at 10 mg/kg, and Cyp17a1 at 200 mg/kg paralleling with their protein levels. TMBPA compromised the expression of Esr1, while increased the expression of Cdk2 and Cdk4 as well as their protein levels. TMBPA particularly increased the phosphorylation of AKT1 and AKT2 at 200 mg/kg. In conclusion, the present study suggests that TMBPA may promote FLC proliferation via ESR1-CDK2/4-AKT pathway, while inhibits the function of FLCs by reducing steroidogenic enzyme activity.