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Emergency Medicine

May J. Yen, MD

Works at hospitals in South el Monte, CA · Mission Viejo, CA · Orange, CA · California

Summary

May J. Yen, MD (Emergency Medicine) is listed by Medicare at 3 hospitals in South el Monte, CA, Mission Viejo, CA and Orange, CA. NPI 1326227232. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about May J. Yen, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Emergency MedicinePrimary specialty
YesAccepts Medicare assignment
20Years since medical school (graduated 2006)
University Of Maryland School Of MedicineMedical school
MaleGender (as listed)
Regents of the University ofGroup practice (+1 more)

Quick answers

Which hospitals does May J. Yen work at?
Medicare's official clinician data lists May J. Yen at 3 hospitals: Greater El Monte Community Hospital, Providence Mission Hospital and UCI Health-Orange. This is where the clinician works or has privileges; call the hospital to confirm.
Where does May J. Yen see patients?
Medicare's clinician data lists 3 practice locations, including Orange, CA, South El Monte, CA and Monterey Park, CA. Call before your visit to confirm the address.
What is May J. Yen's specialty?
Medicare lists Emergency Medicine as the primary specialty.
Does May J. Yen accept Medicare assignment?
Yes. Medicare's clinician data says May J. Yen accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for May J. Yen?
(714) 456-7004, as listed in official Medicare / NPI Registry data.
What is May J. Yen's NPI number?
1326227232. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where May J. Yen works

Medicare's Facility Affiliation Data lists May J. Yen at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where May J. Yen is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists May J. Yen as a member of these groups (CMS data updated 2026-10-02).

  • Regents of the University of129 clinicians in the group
  • Gem Medical Group Corporation57 clinicians in the group

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in Orange

Clinicians with the same Medicare primary specialty in Orange, CA — not a recommendation.

All emergency medicine doctors in Orange →

Clinician information

CredentialMD
Medical schoolUniversity Of Maryland School Of Medicine
Graduation year2006
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1326227232
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians