She'll blow up like Phil Heath on slin sooner then it takes to wipe your ass, so take action or you may wake up one day and find yourself in a situation where you have a fukkin kid or two on your shoulders and a whale on the bed that does nothing but keeps your depression of unfulfilled dreams of youth going, till' you'll start feeling old and washed up, then you'll start drinking occasionally and when you'll really become old you'll sit behind your 3d floating in the air hologram monitor and preach young bucks on getbig how they should marry their fat bitches, have kids and live a beautiful, "right" life, because you'll have an urge to drag someone with you in the shithole you fell once upon a time...
OR
you could force her to develop a habit of keeping herself in shape................... ...and fuck young, nice and tight whores on the side, just to make sure you aren't missing on anything.
BTW - if she still hasn't had a child........I'm afraid you will be unpleasantly surprised with the direction her body takes after bearing one.