A new study published Tuesday in the journal Molecular Psychiatry may provide insight into why males are more likely to be affected by autism spectrum disorder (ASD) than females. Recent statistics indicate that ASD is five times more common in boys (1 in 42) as compared to girls (1 in 189).
Researchers from the University of Cambridge in England and the Statens Serum Institute in Copenhagen utilized the Danish Historic Birth Cohort and Danish Psychiatric Central Register to analyze prenatal amniotic fluid samples of 128 males who were later diagnosed with a form of ASD in comparison to a set of typically developing controls. They found that levels across all steroid hormones, such as progesterone and testosterone, were elevated in the group diagnosed with ASD. This indicates that increased steroid hormone levels may have deleterious effects on fetal brain development, whether independently or through interactions with other developmental factors.
Previous research has indicated a link between elevated levels of testosterone in the womb and developmental delays. This study is the first of its kind to draw a connection between increased levels across all steroid hormones and a diagnosis of autism.
The team of scientists stressed that expectant mothers shouldn't use steroid hormone blockers, since this may lead to other harmful side effects, nor should this signal a need for prenatal screenings, as this data does not definitively predict a diagnosis. Rather, it suggests variations in the vulnerability of certain individuals to such levels of hormones.
In addition, the results of this study further affirm that the development of autism spectrum disorder is linked to prenatal factors during pregnancy, rather than external factors such as vaccines. More research is needed to ascertain what leads to elevated hormone levels in the womb, as well as why these hormones leave males more vulnerable to an autism diagnosis than females. This study could also benefit from analysis of amniotic fluid samples of females. Nevertheless, as more research points to an earlier diagnosis of autism, the possibility for earlier interventions increases exponentially, leading to more positive outcomes for those diagnosed on the spectrum.