Imagine you are in charge of a modern Western nation. The decision is made that it is in the vital longterm interest of the nation to get the birthrate to 2.5-3.0 per woman. It is also important to get the marriage rate back to all time highs. You also want to get people married younger and having children younger, ideally having their children in their early-to-mid 20s so that they have more energy as parents, grandparents are younger and more active, and the population grows more quickly. Finally, you want to bring the divorce rates down to near all-time lows. Strong and lasting families, for all ethnic groups, is your #1 priority.

What changes, legal, governmental and cultural, would be the best way to do this in a way that is fairest to both genders?