The difference is that a woman has to take time off (for health reasons), whereas the man can take time off. Economically, there is a penalty for taking time off (lower salary, lower skills, lower future earnings), its economically rational to not take time off. But only a man can make that choice.
So the employer cannot rely anymore on a man not taking time off.
(The total amount without is about three years instead of 14 months, but only those 14 months are covered financially).