doctors in private practice are not required to provide interpreters. Hospitals are required because hospitals are place of public accommodations regardless of whether they are the recipients of federal financial assistance.
ADA Home Page - ada.gov - Information and Technical Assistance on the Americans with Disabilities Act and
DisabilityInfo.gov: Disability related information and resources from the Federal Government have more. beside better to have the doctor write back and forth so you can check more on google and wikipedia and
National Institutes of Health (NIH) - Home Page why have an interpreter know you have STD or you're pregnant or etc???