Declining After Acceptance?

[SSFL]

I'd love some insight on this situation. I received my MA in history from X University. I also work there as an online instructor. I applied for their PhD Program in history for this coming fall. Currently, I live out to state, but my husband works for a nation-wide company, so, we simply planned for him to apply for a transfer to the city where X University is located, move down, and start school there were I accepted. 

Well, between my application and my eventual acceptance, we found out we were - surprise! - expecting baby #5. This was a daunting fact considering my due date is 10 days prior to the start of classes, and we'd have to move across country to a city where we have no family or friends when I was heavily pregnant. However, I had children while working on both my undergraduate and graduate degrees in the past, so we figured we could manage, and I ACCEPTED the offer of acceptance when it was made. 

Now, my husband is waiting to hear back about several applications he's made for jobs with his company near X University. The problems? While he's been waiting, the boss at his current location has offered him his choice of two local positions - both great career opportunities and both requiring a 2 year contract. Moving into one of those positions would make a move closer to X University easier - and more lucrative - in the future. It would also allow us to remain close to our family and friends while having a fifth child. All of these factors are making me consider declining my acceptance offer. My question? If I were to decline, would I stand any chance at all of being accepted again if I decided to apply after my husband's two year contract locally was up? I don't want to burn bridges with X University. After all, the program really suits my research interests, and I also work there. That said, I want to do what's best for my family as a whole, not just myself. 

[Concordia]

Can you negotiate a deferral for maternity leave?  Postponing everything for a year may clear up what you really want to do.

[SSFL]

15 minutes ago, Concordia said:

Can you negotiate a deferral for maternity leave?  Postponing everything for a year may clear up what you really want to do.

As far as I understand the deferral process at my school, I can apply for a deferral for up to one year. However, if they reject my deferral request, I am automatically out of the program. They also tend to be skeptical of personal reasons for deferral - usually it's only financial issues that result in a request being accepted. I hesitate to request a deferral for fear that I may lose my opportunity all together. 

[Concordia]

Still, delivering a child isn't really a negotiable item.  Maybe inquire informally?