Outside of the maternity leave issue there's a cultural issue with stay at home dads. I believe in essentially all countries, if the family isn't financially secure, it's assumed the dad's a bum, so leaving the financial situation to your better half feels like it can backfire.

Worded like this it sounds stupid but it's just one of those things..

There used to be similar assumptions around women working - it was seen as neglecting their family. Culture can change.