While it is understandable that you are anxious to get settled in a new home before your next child is born, several things will have to take place before you are ready to do that. You say "new jobs" If you are currently employed and can show a strong employment history, you may be able to get pre-approved for a loan now. However, most lenders will want to see a minimum of 6 months continuous employment and/or a strong credit history. Pre-approvals are usually only valid for two months, so obtaining one now would be instructive as to how much of a loan you would qualify to take, but you would have to have a new pre-approval when you begin the housing search in earnest.
Pre-approval is not necessary to look at houses, if you have a good idea of how much you will be able to borrow, but most agents justifiably are not willing to do a lot of searching with you unless you can prove to them and to the prospective sellers that you are able to buy the houses you are looking at. With all the resources available online to look at multiple pictures and virtual tours, much of your hunting can take place on the internet.
If neither of you has a new job yet, that would seem to be a crucial factor in even deciding where you will settle. Commuting distances, available child care, access to main highways, and services are all things to be taken into consideration. In an area like Cranberry, even a difference of a few miles can make a large impact in commuting times. Right now, the market is extremely active and buyers are finding that it is less of a buyers' market than it once was. Will you have to sell a house to buy a new one? If so, that will greatly impact your decision at this end.
I probably over-answered your question, but I hope that this has helped. This is a great area. Good luck with your plans.