Katherine Seiler Harkess, M.D.
Obstetrics & Gynecology · O'fallon, MO
At a glance
300 Winding Woods Drive Suite 200, O'fallon, MO 63366
NPPES record updated Mar 25, 2020. Public records can lag behind changes at a practice.
Before you call: a quick checklist
- Are you accepting new patients?
- Do you accept my specific insurance plan?
- Do you provide the service I need at this address?
- Do I need a referral, and what is the earliest appointment?
Insurance participation and appointment availability are not established by these public records.
Medicare & insurance
Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.
How to check your coverage
Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.
Check the official Medicare directory ↗Practice location
300 Winding Woods Drive Suite 200O'fallon, MO 63366
Additional reported practice locations
615 S New Ballas RdOb/Gyn
Saint Louis, MO 631418221
Phone: 3142516062
Fax: 3142514376 15945 Clayton Road Suite 305
Ballwin, MO 630118221
Phone: 6362565090
Education & affiliations
- Medical / professional school
- Not reported in this file
- Graduation year
- 2015
- CMS specialties
- Obstetrics/Gynecology
Practice groups
Reported hospital affiliations
- Huntsville Hospital Huntsville, AL
Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.
Source: CMS National Downloadable File · Published Oct 15, 2026.
Source: CMS Facility Affiliation Data · Published Oct 15, 2026.
Procedures in the public data
Reported activity can help you ask more informed questions about a practice’s services.
No displayed procedure-category record in this release. This does not mean the clinician performs no procedures.
CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology
Source: CMS Utilization Data · Published Oct 15, 2026.
Service-mix comparison is unavailable for this NPI in the imported Medicare service file.
Industry-reported general payments
Includes reported transfers of value, such as meals, travel, or consulting. Payments do not establish improper conduct or quality of care. Research funding and ownership values are excluded from this total.
See payment purposes and reporting companies
Reported purposes
| Purpose | Amount |
|---|---|
| Food and beverage | $34.76 |
Reporting companies
| Company | Amount |
|---|---|
| MEDTRONIC, INC. | $34.76 |
Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.
Professional details: NPI, taxonomy & registry record
Registry details
- Primary taxonomy
- Obstetrics & Gynecology
- Taxonomy code
- 207V00000X
- Enumeration date
- Jun 16, 2015
- Record updated
- Mar 25, 2020
More registry details
- Provider type
- Individual · Type 1
- Reported credentials
- M.D.
Reported taxonomies and licenses
207V00000X · Primary
License reported: 2019026841 MO
License numbers and credentials are reported to NPPES; HCPList does not independently verify them.
Practice location
300 Winding Woods Drive Suite 200O'fallon, MO 63366
- Phone
- (636) 240-0130
- Fax
- (636) 240-6822
Mailing address
300 WINDING WOODS DRIVE SUITE 200O'FALLON, MO 63366
Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.
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