Earlier quoted context omitted.
Parenthood is by far the most subsidized personal choice in the universe. Let's not pretend it's not. Some countries give more than a year paid parental leave, in what can only be described as vote purchasing. Parenthood is compensated.
It is really not compensated if you look at the financial side. The cost of raising a child plus the lost income because of parenting plus the fact that 'you remain flat' is way higher than months or even a year extra pay. It is worth it though for most people (because of the extra happiness) so I'm not saying that we should necessarily compensate it further, just that financially it's not compensated for.
It's a personal choice to have children, and it's impossible to be a parent X hours a day and also spend those same X hours "in the lab".
Just like it's not possible to spend all your time in the lab and also be a (present) parent.
The limited time for everything that can be done in a lifetime is not about "fairness", and nobody owes you to be able to do all things in life, even if it were possible, which it isn't.