Maria Siu, D.O.
Obstetrics & Gynecology Physician · Pomona, CA
Maria Siu, D.O. is an obstetrics & gynecology physician with a practice address in Pomona, California, and NPI 1144513862, issued on May 27, 2011. Check the license (California 20A13839, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Maria Siu
- Credential
- D.O.
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License numbers
- 20A13839 CA
P26504 MD
Self-reported in NPPES; status is on the state search - Practice location
- 160 E Artesia St Ste 330, Pomona, CA 91767
- Phone
- (909) 622-5654
- Enumerated
- May 27, 2011
- Record last updated
- May 8, 2018 (not updated in 8 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Also registered at 160 E Artesia St Ste 330
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Simmi Dhaliwal, M.D.Obstetrics & Gynecology Physician1275638009
- Maggie Pham, D.O.Obstetrics Physician1073907044
- Kelly Smith, M.D.Obstetrics & Gynecology Physician1164955498
Verify Maria Siu in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A13839Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
92% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
14 Medicare Part D claims for 11 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Maria Siu among 5,088 obstetrics & gynecology physician records in California
Maria Siu, D.O. is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2011, is newer than 72% of them.
- NPI issued2011 · 72% of these records are older, 25% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileNo · 53% of these records are
- Record last updated2018 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Obstetrics & Gynecology Physician providers in California
There are 5,088 obstetrics & gynecology physician records in California.
All 5,088 in California → Every provider in Pomona → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Tahira Akram, MDPomona, CA 917671942202825
- Frank Chiang, MDPomona, CA 917671457456287
- David Choi, M.D.Pomona, CA 917671881947117
- Stephanie CropperPomona, CA 917671366547192
- Francisco Cuellar, M.D.Pomona, CA 917671336102797
- Simmi Dhaliwal, M.D.Pomona, CA 917671275638009
- Abdul Kublan, MDPomona, CA 917671396242186
- Ju Rhee, MDPomona, CA 917671285607903
Common questions
What is Maria Siu, D.O.'s NPI number?
Maria Siu, D.O.'s National Provider Identifier (NPI) is 1144513862, issued on May 27, 2011. An NPI identifies a provider in billing; it is not a license.
Where is Maria Siu, D.O. located?
The NPPES record lists a practice address at 160 E Artesia St Ste 330, Pomona, CA, 91767. Phone: (909) 622-5654. Providers update this record themselves, so call before visiting.
How can I verify Maria Siu, D.O.'s license?
NPPES lists California license number 20A13839, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Maria Siu, D.O. prescribe under Medicare Part D?
In 2024, Maria Siu, D.O. had 14 Medicare Part D claims for 11 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.