Margaret Ryan Markham, M.D.
Obstetrics & Gynecology Physician · Houston, TX
Margaret Ryan Markham, M.D. is an obstetrics & gynecology physician with a practice address in Houston, Texas, and NPI 1770803967, issued on Jun 10, 2010. Check the license (Texas P9903, as entered in NPPES) on the Texas Medical Board; the Medicare figures below come from public CMS files.
- Name
- Margaret Ryan Markham
- Credential
- M.D.
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- P9903 TX
Self-reported in NPPES; status is on the state search - Practice location
- 7400 Fannin St, Houston, TX 77054
- Phone
- (713) 795-1000
- Enumerated
- Jun 10, 2010
- Record last updated
- Jan 26, 2022
- Fax
- (713) 795-1011
- Medicare enrollment
- Enrolled (PECOS I20150515000631); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 3,524 in Texas → Look up another NPI →
Also registered at 7400 Fannin St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Alagappan Alagappan, M.D.Neonatal-Perinatal Medicine Physician1043341415
- Cynthia Ashdown, RN ANPRegistered Nurse1255333712
- Richard Carney, MDInternal Medicine Physician1124018544
- Anayi Castillo, LPCProfessional Counselor1841120540
- Anna Clark, MSNFamily Nurse Practitioner1144657602
- Quentin Collard, M.D.Pediatrics Physician1841391554
Verify Margaret Ryan Markham in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersTexas Medical Board
Search for license P9903Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
48% more Medicare Part D claims than the average obstetrics & gynecology physician in 2024
244 Medicare Part D claims for 87 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D. Brand-name drugs were 20% of claims.
Most prescribed
- Estradiol83 claims
- Valacyclovir31 claims
- Premarin21 claims
- Gabapentin12 claims
- Estradiol (Twice Weekly)11 claims
- Progesterone11 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $132.24
7 payments; by number, the most common kind was food and beverage; the largest payer was Sage Therapeutics, Inc. The 21,429 providers of this specialty with any payment received $1,030.61 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Hwca, PLLCPearland, TX
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Margaret Ryan Markham among 3,524 obstetrics & gynecology physician records in Texas
Margaret Ryan Markham, M.D. is one of 3,524 obstetrics & gynecology physician records with a practice address in Texas. 78% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2010, is newer than 64% of them.
- NPI issued2010 · 64% of these records are older, 33% newer
- In a Medicare fileYes · 78% of these records are
- In the CMS Doctors and Clinicians fileYes · 59% of these records are
- Graduated2010 · median 2005 among the 2,093 with a school on file
- Record last updated2022 · 54% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a Texas practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Obstetrics & Gynecology Physician providers in Texas
There are 3,524 obstetrics & gynecology physician records in Texas.
All 3,524 in Texas → Every provider in Houston → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Karolina Adam, MDHouston, TX 770541326049891
- Maryam Baird, M.D.Houston, TX 770541063415255
- Dawn Black, M.D.Houston, TX 770541710980909
- Stephen Cone, M.D.Houston, TX 770541912900184
- Jason Cooper, M.D.Houston, TX 770541326041484
- Sebastian Faro, MD PHDHouston, TX 770541356342315
- Patrice Firpo, M.D.Houston, TX 770541982607032
- James Gullett, M.D.Houston, TX 770541811990864
Common questions
What is Margaret Ryan Markham, M.D.'s NPI number?
Margaret Ryan Markham, M.D.'s National Provider Identifier (NPI) is 1770803967, issued on Jun 10, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Margaret Ryan Markham, M.D. located?
The NPPES record lists a practice address at 7400 Fannin St, Houston, TX, 77054. Phone: (713) 795-1000. Providers update this record themselves, so call before visiting.
How can I verify Margaret Ryan Markham, M.D.'s license?
NPPES lists Texas license number P9903, as entered by the provider. Search the Texas Medical Board at https://profile.tmb.state.tx.us/Search.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Margaret Ryan Markham, M.D. prescribe under Medicare Part D?
In 2024, Margaret Ryan Markham, M.D. had 244 Medicare Part D claims for 87 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.