Stella Sien, D.O.
NPI 1558592444 · Obstetrics & Gynecology Physician · Colton, CA
Enrolled with Medicare as Practitioner - Obstetrics/Gynecology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Stella Sien, D.O. is a Obstetrics & Gynecology Physician provider in Colton, CA (NPI 1558592444).
Provider details
- NPI number
- 1558592444
- Entity type
- Individual
- Primary specialty
- Obstetrics & Gynecology PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Female
- Sole proprietor
- Yes
- License
- 20A9946 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
16 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2009-07-27
- Last updated
- 2021-11-17
- Certified
- 2021-11-17
Frequently asked questions
- What is Stella Sien's NPI number?
- Stella Sien's National Provider Identifier (NPI) is 1558592444, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Stella Sien's specialty?
- Stella Sien is listed in the NPPES registry with a primary specialty of Obstetrics & Gynecology Physician (Allopathic & Osteopathic Physicians).
- Where is Stella Sien located?
- Stella Sien's practice location on file with NPPES is 400 N Pepper Ave, Colton, CA 92324-1801.
- What is Stella Sien's phone number?
- The practice phone number listed in the NPPES registry for Stella Sien is (909) 580-3470.
- Does Stella Sien accept Medicare?
- Stella Sien is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Stella Sien's NPI active?
- Yes — Stella Sien's NPI (1558592444) is active in the NPPES registry as of the last update on 2021-11-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.