I wouldn’t bring it up in the interview - they are not allowed to ask and you are not required to disclose medical information at an interview.  You would become eligible for FMLA Leave after working for them for 1 year or 1200 hours, as long as the employer has 50 or more employees withing a 75 mile radius.  This may vary in your state, but that is the minimum standard.  States are only allowed to modify federal FMLA entitlements if what that individual state offers is more generous.  You are entitled (under federal guidelines) to up to 12 weeks of leave per year for eligible occurences after meeting the above requirements.  Keep in mind that most employers use a ’rolling year’ instead of a calendar year.  This means that your year begins on the first day that you request FMLA Leave, regardless of the calendar date.  This prevents people from being able to stack leave, which in practice would allow someone to take off for six months straight if they took the last three months of one year and the first three months of the next year.

Hope this helps,