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Obstetrics/Gynecology

Carey R. Martens, DO

Works at hospitals in Weston, WI · Wisconsin

Summary

Dr. Carey R. Martens, DO is an OB-GYN at 1000 N Oak Ave, Marshfield, WI 54449. Phone: (715) 387-5511. Accepts Medicare assignment. In 2024, Carey R. Martens had 12 Original Medicare patients and 18 services. NPI 1598880833. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: OB-GYN (Medicare lists Obstetrics/Gynecology)
  • Address: 1000 N Oak Ave, Marshfield, WI 54449 · Directions (1 more location)
  • Phone: (715) 387‑5511
  • Medicare: Accepts Medicare assignment
  • Hospital: Marshfield Medical Center - Weston
  • Group practice: MCHS Hospitals Inc
  • Medical school: Touro Un College Of Osteopathic Medicine, Vallejo · graduated 2003 (23 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Carey R. Martens, 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 Carey R. Martens accept Medicare assignment?
Yes. Medicare's clinician data says Carey R. Martens 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 Carey R. Martens see?
In 2024, CMS data shows 12 Original Medicare patients and 18 services for Carey R. Martens. This counts Original Medicare only and measures volume, not quality.
What is Carey R. Martens's NPI number?
1598880833. 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 Carey R. Martens, 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 patients12
Services billed to Medicare18
Different services or procedures5
Participating Medicare providerYes
Average age of these patients63

Hospitals where Carey R. Martens works

Medicare's Facility Affiliation Data lists Carey R. Martens at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Carey R. Martens is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Carey R. Martens as a member of this group (CMS data updated October 2, 2026).

  • MCHS Hospitals Inc1,197 clinicians in the group

Specialties

Find other Obstetrics/Gynecology doctors in Wisconsin →

Other OB-GYNs in Marshfield

Clinicians with the same Medicare primary specialty in Marshfield, WI — not a recommendation.

All OB-GYNs in Marshfield →

Other clinicians in MCHS Hospitals Inc

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

Clinician information

CredentialDO
Medical schoolTouro Un College Of Osteopathic Medicine, Vallejo
Graduation year2003 (23 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1598880833
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians