Germany has this, with Gleitzeit (you can spread your working hours over the course of the month), but some jobs really need a tight shift schedule, as otherwise the customers show up and lights are out.

I think the latter are simply not jobs appropriate for everyone. Not just fertile women. Also, family men or those caring for the disabled or elderly, or anyone with chronic illness, can't always just jump up and run out the door and stand at a machine for 8 hours straight .