How long to wait?

I'm currently 16+2. My husband and I have been discussing our options after baby comes. We tried for 15 years to get this baby so we were shocked when I ended up pregnant. But we're not sure what to do afterwards as far as birth control or preventative measures. I'm not opposed to a second baby, but I don't want to wait too long. I'll be 37 when I deliver. My plan is to give it a year to a year and a half to see what happens and then decide a plan of action from there. Does anyone else have a plan in place? What is your personal age cutoff?