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Dr. Gregory W Siewny, MD

Obstetrics & Gynecology Physician in Franklin, OH · enumerated 2005.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1891791216

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Registry record

Entity type Individual (Type 1)
Name Dr. Gregory W Siewny
Credential MD
Sex Male
Practice address 200 Medical Center Dr, Suite 160, Franklin, OH, 45005
Phone (513) 424-1440
Fax (513) 424-1422
Enumeration date Jun 21, 2005
Last updated in NPPES Apr 24, 2015

Taxonomy & licenses

207V00000X Obstetrics & Gynecology Physician Allopathic & Osteopathic Physicians · License 35049923 (OH) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for Gregory Siewny?
The National Provider Identifier (NPI) for Gregory Siewny is 1891791216, a Type 1 (individual) record in the CMS NPPES registry.
Where does Gregory Siewny practice?
The practice location on file with NPPES is in Franklin, OH. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-04-24.