It’s at least understandable why Jordana Brewster felt this way initially.
Brewster did not need to go through this, and so she thought maternity leave was not for her.
She seems to feel she would be somewhat selfish, taking the same time that others need because they have been through childbirth.
Certainly part of the need for maternity leave is that childbirth is, at the very least, exhausting, and can also lead to numerous other health issues.