Why do they not say "The Baby"

https://www.youtube.com/watch?v=HkXnhlCkVPM

In this video he says "put baby in" and not "put the baby in" Also, in other baby type videos they say "place baby inside" or "now you can see that baby and mom are happy"

There is no "the baby" or "the baby's mom" or "the mom".

The video is one example of many. I asked someone who said it is something to do with the agenda of keeping people happy and not offended by mentioning a gender. I don't think this is true though.

Solution 1:

'Baby' and 'Mom' are being used as substitutes for names, just as you might say to a small child 'Where's Mommy?' rather than 'Where is your mother?'

Solution 2:

Saying just 'baby' or just 'mom' is using those words as names.

Using 'the' in front of the other person is like using the third person for yourself. Without 'the' it's like you're using their first name as though it is 'Baby'. It sounds weird and is probably weirder sounding than using 'the', because 'baby' is a weird name for someone). But it is the way to refer to babies in these situations.

I don't think it is transferable to other situations. For example, you don't usually say 'Boxer then plants his fist in Opponent's jawbone'

Solution 3:

In the BBC series "The Midwife", which follows a group of midwives in London's East End in the 50's, they use this all the time. The midwife will say something like "Well done, mom! You have a beautiful boy!" And "Here's baby, why don't you try feeding her."
It creates a kind of professional intimacy: the woman is the midwife's patient but it's a bit more than getting the child delivered. The midwife often spends hours with the woman during the delivery, guiding her through a messy, physical, life-changing event, especially if it's a first child. Addressing the woman as 'mom' stresses the transition into her new role. Likewise, speaking of the child as 'baby' gives it a more personal touch without becoming too specific: it's not about little Jenny or Johnny as an individual but about its functioning needs as a baby.