I would get started with med school. You'll have several months at home for starters. Also, looking back, I was home MOST of the time during med school. So, doing M1 year with an infant seems more doable. You might need baby to go to daycare more once they're more active and distracting.

But, honestly, M1 & M2 year, you pretty much make your own schedule! At least we did at my school. They recorded all of our lectures online, and I almost always did them at home. (I loved being able to pause halfway through to make sure I got a point or could look up something that didn't make sense.)
Also, you're going to want baby #2 probably at some point; so, I would get started with med school.