Take both.

Invest for a short term period, a year or two. Or if you have the patience to wait and want to see your money grow, aim for a long term period of investment. You should also consider the risk of the investment.

Save the money if you think you will be needing it in a shorter period of time (within a year or shorter), like your wife is in a labor in a few months or so.

I usually do this kind of formula, 15% savings - 30% investment.