As in, “He was assigned male at birth.” It sounds like other options were available, doesn’t it? Like a child being assigned a name or a house at Hogwarts.
Is there any plausible scenario where the child would be assigned anything other than male at birth?
Suppose the doctor said, “I assign this child as female.” And then the parents freak out and say “Are you fucking nuts?! He’s not female, he’s got a penis.”
“Hmmm,” says the doctor. “Well . . . you’ve got me there.”
If it wasn’t so easy to determine the sex of a newborn at a glance — it doesn’t require a medical degree — you could go with a DNA test, since every cell in the human body is marked male or female. That never changes, no matter how many hormones you take or how many surgeries you have. It’s biological and permanent.
In fact, although this does require some training, a person with relevant expertise can tell you if a child is male or female before birth, via an ultrasound,
Babies don’t exist in the womb like Schrodinger’s cat — could be male, could be female — we’ll have to wait and see what the doctor assigns.
Babies are male or female at conception. They’re not “assigned at birth.”