I may need a little more information about your thoughts/plans/questions to better advise... are you considering quitting before, after, or during the application process? You mentioned starting a family, is that part of the rationale for potentially quitting, or just to search for a new job? Do you have a strong desire to pursue a part-time program vs full-time?
Certainly during the application process, to be successful, schools will want to know what your 'plan' is.... where you are working/plan to work during the program, why you are interested in an MBA at all, a part-time program, and their school; how you plan to use the degree, etc. So no matter what, you'll need to have a compelling story to answer those questions, and honesty about your plans always comes across more genuinely... so I would advise really thinking over your plans and rationale and first determine the best plan for YOU and your career, and then you can determine whether, or how, it may affect applications/admissions.
Hope that helps!
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