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Obstetrics/Gynecology

Josephine Doo, MD

Works at hospitals in Martinez, CA · California

Summary

Josephine Doo, MD (Obstetrics/Gynecology) is listed by Medicare at 1 hospital in Martinez, CA. NPI 1336670116. 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 Josephine Doo, 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

Obstetrics/GynecologyPrimary specialty
YesAccepts Medicare assignment
9Years since medical school (graduated 2017)
University Of Missouri, Kansas City, School Of MedicineMedical school
FemaleGender (as listed)
Peter a Castillo MD IncGroup practice

Quick answers

Which hospitals does Josephine Doo work at?
Medicare's official clinician data lists Josephine Doo at 1 hospital: Contra Costa Regional Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Josephine Doo see patients?
Medicare's clinician data lists 1 practice location in Los Gatos, CA. Call before your visit to confirm the address.
What is Josephine Doo's specialty?
Medicare lists Obstetrics/Gynecology as the primary specialty.
Does Josephine Doo accept Medicare assignment?
Yes. Medicare's clinician data says Josephine Doo 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 Josephine Doo?
(925) 905-9922, as listed in official Medicare / NPI Registry data.
What is Josephine Doo's NPI number?
1336670116. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Josephine Doo works

Medicare's Facility Affiliation Data lists Josephine Doo 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 Josephine Doo is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Josephine Doo as a member of this group (CMS data updated 2026-10-02).

  • Peter a Castillo MD Inc2 clinicians in the group

Specialties

Find other Obstetrics/Gynecology doctors in California →

Other OB-GYNs in Los Gatos

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

All OB-GYNs in Los Gatos →

Clinician information

CredentialMD
Medical schoolUniversity Of Missouri, Kansas City, School Of Medicine
Graduation year2017
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1336670116
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