Actually and statistically speaking, the moment of birth of child is the least sensitive/painful moment, because mom is just over the charts thinking about pushing.
The moments before that are the worst moments... and that's why I listed child labor pain... but I now that I have seen I missed the birth word... (too late now) =) I am guessing you wanted to choose that one. Ups.. sorry for the mistake.
So child labour is not about children doing work. :) I wondered how that one came into this list, but I did not jump to the right conclusion, sorry. It is one of the expressions we did not learn at school. Now that I come to think of it, the english language found a pretty well fitting expression.
yeah... my bad sorry. 😁