Explainer: Sometimes the body mixes up male and female
https://student.societyforscience.org/article/explainer-sometimes-body-mixes-male-and-female
Society for Science/By Amanda Leigh Mascarelli 11:18am, July 31, 2015
"Boys and girls are different. It seems so obvious. Yet some medical conditions may cause some of those differences to become confused. And then telling apart boys from girls can prove challenging.
It's one measure of how complex human biology is.
When it comes to whether someone looks like a boy or girl, hormones clearly run the show. For instance, a newborn girl's genitals may appear somewhat or totally male if that baby had encountered too much of the hormone testosterone (tess-TOSS-tur-own) in the womb. Similarly, too little of this hormone can impair ."