ABC News (http://www.abcnews.go.com/2020/story?id=3088298&page=1)
By ALAN B. GOLDBERG and JONEIL ADRIANO
Parents of Transgender 6-Year-Old Girl Support Her Choice
No one knows why children like Jazz are transgender -- there are only theories. Through the first eight weeks of pregnancy, all fetuses' brains look exactly the same: female, nature's default position.
Only after testosterone surges in the womb do male brains start to develop differently. Some scientists suggest that a hormone imbalance during this stage of development stamped the brains of transgender children with the wrong gender imprint.