Quick answers
- Which hospitals does Haydan E. Ommen work at?
- Medicare's official clinician data lists Haydan E. Ommen at 1 hospital: Mercy Hospital South. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Haydan E. Ommen see patients?
- Medicare's clinician data lists 4 practice locations, including Saint Louis, MO and Chesterfield, MO. Call before your visit to confirm the address.
- What is Haydan E. Ommen's specialty?
- Medicare lists Physician Assistant as the primary specialty.
- Does Haydan E. Ommen accept Medicare assignment?
- Yes. Medicare's clinician data says Haydan E. Ommen 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 Haydan E. Ommen?
- (314) 525-4440, as listed in official Medicare / NPI Registry data.
- What is Haydan E. Ommen's NPI number?
- 1699525121. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Haydan E. Ommen works
Medicare's Facility Affiliation Data lists Haydan E. Ommen at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Mercy Hospital SouthSaint Louis, MO · Acute Care Hospital · CCN 260077
Practice locations
Addresses where Haydan E. Ommen is enrolled with Medicare (CMS data updated 2026-10-02).
- 10050 Kennerly Rd, Suite 25200Saint Louis, MO 63128 (314) 525‑4440
- 12700 Southfork Rd, Suite 100Saint Louis, MO 63128 (314) 543‑5284
- 14825 N Outer 40 Rd, Suite 200Chesterfield, MO 63017 (314) 336‑2555
- 621 S New Ballas Rd, Suite 3005bSaint Louis, MO 63141 (314) 567‑5850
Group practices
Medicare enrollment lists Haydan E. Ommen as a member of these groups (CMS data updated 2026-10-02).
- Mercy Clinic Surgical Specialists LLC182 clinicians in the group
- Orthopedic Center of St Louis Img LLC6 clinicians in the group
Specialties
- Physician Assistantprimary
Other physician assistants in Saint Louis
Clinicians with the same Medicare primary specialty in Saint Louis, MO — not a recommendation.
Clinician information
| Graduation year | 2023 |
|---|---|
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1699525121 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians