This week’s podcast focuses on the Extreme Male Brain Theory of autism, originating from the idea that autism, in part, is a reflection of increased fetal testosterone levels.  Amazingly, fetal testosterone levels are reflected in the length of the 2nd and 4th fingers and can be measured as a reflection of testosterone levels during pregnancy. Research, including those from a recent CDC study, have reinforced that elevated fetal testosterone levels play a role in autism in males, but not females.  Differences in fetal testosterone across gender and diagnosis has also been observed in a study from Drexel University.  What was observed in males is not observed in females.  It doesn’t mean the theory is wrong, it means that what is true for one sex is not always true for the other.

https://www.ncbi.nlm.nih.gov/pubmed/29450837