Kiwi2 ~ Just to clarify... I've been out of NZ for 3 years, got married (on visitor visa) in the US last year, before moving to Singapore later in the year. So I already have the dependants pass (and anything else like credit card here) in my single name, as they'll only use what's in my passport. I don't mind having all my documents here in my maiden name, as we're here on a short term assignment with my husbands work (another 18 months probably).
The issue with the name change is that we are in the process of applying for a US spouse visa, to give me permanent residency status in the US. If I'd got my passport endorsed with married name before April of this year, it wouldn't be a problem. (Was planning to get it done on a trip to Sydney or NZ in the next few months, during my middle trimester... until I found out it was too late a week ago!)
So now I'm unsure as to whether to go ahead and get a new NZ passport before getting the US spouse visa, so that all my documentation can be in that name, or whether to stick with maiden name for now and change in the future, e.g. once I need a new passport in another 5 years time! The American system seems to be somewhat complex; despite not wanting to get a new p/p now, I do wonder if it would be easier in the long term.
Hope that makes things clearer! Thanks for your thoughts!