Quick answers
- Does Margaretta L. Mendenhall accept Medicare assignment?
- Yes. Medicare's clinician data says Margaretta L. Mendenhall 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 Margaretta L. Mendenhall see?
- In 2024, CMS data shows 39 Original Medicare patients and 51 services for Margaretta L. Mendenhall. This counts Original Medicare only and measures volume, not quality.
- What is Margaretta L. Mendenhall's NPI number?
- 1275730111. 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 Margaretta L. Mendenhall, 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 patients | 39 |
|---|---|
| Services billed to Medicare | 51 |
| Different services or procedures | 11 |
| Participating Medicare provider | Yes |
| Average age of these patients | 70 |
Most frequent services
- Cervical or vaginal cancer screening; pelvic and clinical breast examination (G0101)21 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)14 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 cholesterol75%
- Arthritis49%
- High blood pressure41%
- Osteoporosis31%
- Anxiety28%
Hospitals where Margaretta L. Mendenhall works
Medicare's Facility Affiliation Data lists Margaretta L. Mendenhall 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.
- Mercy Hospital SouthSaint Louis, MO · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 260077
- Mercy Hospital St LouisSaint Louis, MO · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 260020
Practice locations
Addresses where Margaretta L. Mendenhall is enrolled with Medicare (CMS data updated October 2, 2026).
- 15945 Clayton Rd, Suite 305Ballwin, MO 63011 (636) 240‑0130
Group practices
Medicare enrollment lists Margaretta L. Mendenhall as a member of this group (CMS data updated October 2, 2026).
- Mercy Clinic East Communities571 clinicians in the group
Specialties
- Obstetrics/Gynecologyprimary
Other OB-GYNs in Ballwin
Clinicians with the same Medicare primary specialty in Ballwin, MO — not a recommendation.
Other clinicians in Mercy Clinic East Communities
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Saint Louis University School Of Medicine |
| Graduation year | 2007 (19 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1275730111 |
| 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 October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- 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