My son is 1.5 years old now, but I went through this when he was born. First things first...The second your wife shows signs of going into labor, FORGET bodybuilding for 1-2 weeks. Don't be worried about your food, dont even bother with the gym, etc. Just enjoy the experience (or try) and be prepared for exhaustion. This is the craziest time you have in your life. Embrace the madness haha.
You are going to have to slow back on your training a bit for the first months, to avoid sickness. Unless your wife is going to do all the work and you get to sleep 8 hours with no disturbances, you are going to be sleeping like shit for awhile. So don't push yourself too hard in the gym, factor in the limited recovery.
That being said, I made some of the best gains of my life during the first year of my sons life...I was a stay at home dad for the first chunk, and I would be sure to nap whenever he did to help catch up. When my wife got home from work, I went off and worked. Looking back I'm not sure how I squeezed it all in, but if you can do it, you can do anything. I actually enjoyed training a lot in this time (after about 3 months), as it was really my only "alone" time (which you'll need), and also I was much less stressed about it. It was not a priority to me, so I actually enjoyed training.
At the end of the day, give yourself a few weeks to not think bout it, then just focus on pretty much maintenance for awhile. After the first few months, everything balances out and you'll be fine. One benefit to being so damn busy and focused on other things, is if you can stay dedicated, you actually don't even really realize how much progress you are making cause you aren't sitting around obsessing over it. Every few weeks you stop and really analyze and are nicely surprised haha.
Put the focus on your family at this time and just get in what you can!