Job Transition While Spawning

I think I've decided to take the new position. My conflict comes not from the decision to take the job itself, but from my ennui. It seems stressful to have to alter work environments with a new little one at home (they'll let me start after my leave and I'll take on some contract work before then). I just kind of want to sit back right now, wait, and enjoy the status quo. Which is what I think makes me have to take the job. Complacency has always been a major weakness of mine - I blossom in high-stress high-performance environments. I'm definitely one of those people who "plays to their competition", or in this case, performs to the demands of my position. The Breadwinner agrees, and we'll find a way to make the commute thing work - whether it's a new school for the kids closer to my office or a nanny at home.

At the end of the day, I want to go back to the lab. What would I do if I had 20 million dollars? Go back to the lab. What would I do if I didn't have kids? Go back to the lab. The only things preventing me from pursuing science are time and money (both of which are in short supply in a scientific career). I think that's the reason this doesn't feel exactly right. Nothing will ever feel right except exchanging my life for science. But I'm giving editing one more shot, and the added responsibilities and higher pressure environment should help.

The key question remaining is when do I tell my current boss. My first inclination is to tell her immediately so they have time to prepare for my absence/find a replacement if they intend to do that (doubtful). I would be willing to do some contract work for a while to help them out. The problem of course is this may backfire in a major way. I have enough sick days/annual leave to get paid through my leave. But what if they decide to terminate me beforehand (and cut out my insurance???) I can't be uninsured while pregnant or with a newborn... I truly like the people I work with and don't want to screw them over, but I can't seem to find a compromise between the two situations. Any advice on this would be greatly appreciated.