My wife, a high performer with a good motor, did this after we had twins - 3 days a week working from 600-230 as an engineer.

This lasted 3 months before we figured that the difference between what she earned and what we paid the nanny wasn’t worth it.

This was 7.5 years ago, and she hasn’t worked since.

I think much of the success of this plan depends on the individual’s role. In my wife’s case, she was very much client-facing, and they didn’t care about regular days off.

Asking questions will not hurt her career, by the way. Things have really improved in many organizations for new parents in the last decade.

Good luck to you both!