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Obstetrics/Gynecology

Kirstin W. Woo, MD

Sees patients in San Mateo, CA · San Carlos, CA · Los Altos, CA · California

Summary

Dr. Kirstin W. Woo, MD is an OB-GYN at 123 S San Mateo Dr, San Mateo, CA 94401. Phone: (650) 343-4200. Accepts Medicare assignment. In 2024, Kirstin W. Woo had 42 Original Medicare patients and 64 services. NPI 1023144672. 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: 123 S San Mateo Dr, San Mateo, CA 94401 · Directions (2 more locations)
  • Phone: (650) 343‑4200
  • Medicare: Accepts Medicare assignment
  • Group practice: Sutter Bay Medical Foundation
  • Medical school: University Of Pittsburgh School Of Medicine · graduated 2003 (23 years since medical school)
  • Gender (as listed): Female
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Kirstin W. Woo, 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 Kirstin W. Woo accept Medicare assignment?
Yes. Medicare's clinician data says Kirstin W. Woo 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 Kirstin W. Woo see?
In 2024, CMS data shows 42 Original Medicare patients and 64 services for Kirstin W. Woo. This counts Original Medicare only and measures volume, not quality.
What is Kirstin W. Woo's NPI number?
1023144672. 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 Kirstin W. Woo, 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 patients42
Services billed to Medicare64
Different services or procedures14
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)21 services
  2. New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)13 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 cholesterol62%
  • High blood pressure50%
  • Arthritis40%
  • Osteoporosis33%

Practice locations

Addresses where Kirstin W. Woo is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Kirstin W. Woo as a member of this group (CMS data updated October 2, 2026).

  • Sutter Bay Medical Foundation3,829 clinicians in the group

Specialties

Find other Obstetrics/Gynecology doctors in California →

Other OB-GYNs in San Mateo

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

All OB-GYNs in San Mateo →

Other clinicians in Sutter Bay Medical Foundation

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of Pittsburgh School Of Medicine
Graduation year2003 (23 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1023144672
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