Many workplaces are good with helping new mums transition back into work with reduced hours to begin with, and they may be willing to discuss options such as working from home part of the week or even job share, but there's very few who will totally change a position to fit in with an employees needs. You have to keep in mind though that their primary concern is running an efficient business, which may not fit in with your own ideas of a work/life balance. The best thing to do is check your workplace agreement to see what's down on paper and if possible find out what others have done in the same company. Fair work Australia also has some good info on their website - you can even email them about your situation, they will look into it and call you back with info on the appropriate laws.
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