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Obstetrics/Gynecology

Annmarie T. Nguyen, MD

Sees patients in Garden Grove, CA · California

Summary

Dr. Annmarie T. Nguyen, MD is an OB-GYN at 12665 Garden Grove Blvd, Suite 611, Garden Grove, CA 92843. Phone: (714) 539-5225. Accepts Medicare assignment. In 2024, Annmarie T. Nguyen had 49 Original Medicare patients and 136 services. NPI 1083628036. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: OB-GYN (Medicare lists Obstetrics/Gynecology)
  • Address: 12665 Garden Grove Blvd, Suite 611, Garden Grove, CA 92843 · Directions
  • Phone: (714) 539‑5225
  • Medicare: Accepts Medicare assignment
  • Medical school: Hahnemann University College Of Medicine · graduated 1989 (37 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Annmarie T. Nguyen, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Annmarie T. Nguyen accept Medicare assignment?
Yes. Medicare's clinician data says Annmarie T. Nguyen accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Annmarie T. Nguyen see?
In 2024, CMS data shows 49 Original Medicare patients and 136 services for Annmarie T. Nguyen. This counts Original Medicare only and measures volume, not quality.
What is Annmarie T. Nguyen's NPI number?
1083628036. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Annmarie T. Nguyen, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients49
Services billed to Medicare136
Different services or procedures9
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)51 services
  2. Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)38 services
  3. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)24 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis49%
  • Diabetes37%
  • Osteoporosis37%

Practice locations

Addresses where Annmarie T. Nguyen is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Obstetrics/Gynecology doctors in California →

Other OB-GYNs in Garden Grove

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

All OB-GYNs in Garden Grove →

Clinician information

CredentialMD
Medical schoolHahnemann University College Of Medicine
Graduation year1989 (37 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1083628036
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  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