Offered New Position

I'm in my early 30s and working at a company I love. I've been here for 1.5 years and I am definitely overqualified for the admin type role I am in. My manager and team are fantastic but I am pretty bored day to day which is tough because I have always been a high performer. My biggest stressor in this role is that I am not mentally stimulated enough. I was just approached by a different manager in the same department, offering me a position on his team. Pay would only be 2-5% higher, but it would be an actual career type of position whereas I am currently doing admin work. The new role would be more demanding and stressful though. I am finishing my MBA at the end of this year. I've expressed interest in the position and have a pretty good relationship with this manager. He and my current manager are pretty similar.

My dilemma is this: I am tired of putting off having kids and am hoping to get pregnant this summer. I am the higher earner in my marriage, but would really love to be part time after I have a baby. I don't know if either role would let me drop to part time after having a baby, but in my head it seems like it would be less of a hit to my team in the role I am currently in, than the role I have just been offered.

Should I go for the new position or stay where I am? I know I am probably overthinking it. I just waited so long to have kids so I could be in a better position to balance home and work/finances.

If I take this new position, it would open doors to other companies long term if layoffs happened at my company. It's also a role that is commonly offered as a remote position, just not at my company currently. I dont want to be overwhelmed with a baby and a new-ish job, but I want to try and open doors for future opportunities that might better serve my and my family (such as remote and being in an actual career field).