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VALLEY OBSTETRICS & GYNECOLOGY MEDICAL GROUP, INC.
NPI 1144304817
Obstetrics & Gynecology in Colton, CA

Active since October 25, 2006CLIA 05D0947120 · Microscopy
400 N PEPPER AVE, COLTON, CA 92324(909) 580-6333(909) 580-3289 Get Directions Write a Review

NPPES record last updated: May 29, 2020. Verified against the NPPES registry weekly; last sync: November 08, 2026.

About Valley Obstetrics & Gynecology Medical Group, Inc. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

VALLEY OBSTETRICS & GYNECOLOGY MEDICAL GROUP, INC. (NPI 1144304817) is a healthcare organization registered as an obstetrics & gynecology in Colton, California and active in the NPI registry since October 2006. The organization holds a CLIA Microscopy certificate valid through August 31, 2028 and lists Guillermo J. Valenzuela, President, as its authorized official.

NPPES Registry Identity

NPI1144304817
Entity TypeOrganization
Primary Taxonomy207V00000X
Legal Business NameVALLEY OBSTETRICS & GYNECOLOGY MEDICAL GROUP, INC.
Location Address400 N PEPPER AVEColton, CA 92324-1801
Mailing Address400 N. Pepper Ave., Mob 206Colton, CA 92324-1801 · (909) 580-6333 · Fax (909) 580-3289
Phone(909) 580-6333
Fax(909) 580-3289
Organization SubpartNo
Authorized OfficialGuillermo J. ValenzuelaPresident · (909) 580-6333
Enumeration DateOctober 25, 2006
Last NPPES UpdateMay 29, 2020
NPPES CertifiedMay 29, 2020
✔ NPI 1144304817 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyObstetrics & GynecologyAllopathic & Osteopathic Physicians
Taxonomy Code207V00000X
Definition
An obstetrician/gynecologist possesses special knowledge, skills and professional capability in the medical and surgical care of the female reproductive system and associated disorders. This physician serves as a consultant to other physicians and as a primary physician for women.
400 N PEPPER AVE, Colton, CA 92324
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Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Valley Obstetrics & Gynecology Medical Group, Inc. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

20

Medicare enrollment records show 20 clinicians reassign Medicare billing to Valley Obstetrics & Gynecology Medical Group, Inc., which bills Medicare for the services they deliver. Of these, 10 practice within 10 miles. They are listed nearest first.

Clinicians by Medicare Specialty 2

Obstetrics/Gynecology19
Gynecological Oncology1

Clinicians, nearest first (20)

Robert Stowe, DO
Obstetrics/Gynecology
NPI 1568994127
400 N PEPPER AVE
Colton, CA 92324
(909) 580-1000
✔ PECOS✔ Accepts Medicare0.2 mi
Tania Aftandilians, M.D.
Obstetrics/Gynecology
NPI 1780927236
400 N PEPPER AVE
Colton, CA 92324
(909) 580-3470
✔ PECOS✔ Accepts Medicare0.3 mi
Mohammadreza Ghayuri, MD
Obstetrics/Gynecology
NPI 1073711156
400 N PEPPER AVE
Colton, CA 92324
(909) 580-3470
✔ PECOS✔ Accepts Medicare0.3 mi
John Lyons, MD
Obstetrics/Gynecology
NPI 1215905930
400 N PEPPER AVE MOB206
Colton, CA 92324
(909) 580-3470
✔ PECOS0.3 mi
Michelle Mellon
Obstetrics/Gynecology
NPI 1184127128
400 N PEPPER AVE
Colton, CA 92324
(909) 580-1000
✔ PECOS✔ Accepts Medicare0.3 mi
Mallory Novack, D.O.
Obstetrics/Gynecology
NPI 1427324185
400 N PEPPER AVE # 206
Colton, CA 92324
(909) 580-2270
✔ PECOS✔ Accepts Medicare0.3 mi
Kristina Roloff, D.O.
Obstetrics/Gynecology
NPI 1649418401
400 N PEPPER AVE
Colton, CA 92324
(909) 580-3470
✔ PECOS✔ Accepts Medicare0.3 mi
Clarence Sinkhorn, MD
Obstetrics/Gynecology
NPI 1972676195
400 N PEPPER AVE
Colton, CA 92324
(909) 580-6320
✔ PECOS0.3 mi
Guillermo Valenzuela, MD
Obstetrics/Gynecology
NPI 1730263484
400 N PEPPER AVE MOB 206
Colton, CA 92324
(909) 580-6333
✔ PECOS✔ Accepts Medicare0.3 mi
Shirley Wong, DO
Obstetrics/Gynecology
NPI 1346313459
400 N PEPPER AVE DEPT WOMEN'S HEALTH, 2ND FLOOR, MOB
Colton, CA 92324
(909) 580-3470
✔ PECOS✔ Accepts Medicare0.3 mi
Mikio Nihira, MD
Obstetrics/Gynecology
NPI 1326016114
19330 JESSE LN STE 100
Riverside, CA 92508
(844) 827-8000
✔ PECOS✔ Accepts Medicare12 mi
Robert Lopez, M.D.
Obstetrics/Gynecology
NPI 1396836094
12586 CENTRAL AVE
Chino, CA 91710
(909) 548-6820
✔ PECOS✔ Accepts Medicare20 mi
Richard Burwick, M.D., M.P.H.
Obstetrics/Gynecology
NPI 1740471531
1135 S SUNSET AVE STE 208
West Covina, CA 91790
(626) 337-4425
✔ PECOS34 mi
Ernesto Licon, MD
Obstetrics/Gynecology
NPI 1194254896
101 THE CITY DR S
Orange, CA 92868
(714) 880-2911
✔ PECOS37 mi
Samuel Im, M.D.
Obstetrics/Gynecology
NPI 1790839496
12462 PUTNAM ST SUITE 303
Whittier, CA 90602
(562) 900-1012
✔ PECOS✔ Accepts Medicare40 mi
Sam Hessami, MD
Obstetrics/Gynecology
NPI 1831167162
3501 S HARBOR BLVD STE 200
Santa Ana, CA 92704
(949) 284-4996
✔ PECOS✔ Accepts Medicare42 mi
Kristina Nalbandyan, DO
Obstetrics/Gynecology
NPI 1326542382
50 ALESSANDRO PL STE 210
Pasadena, CA 91105
(626) 514-0060
✔ PECOS46 mi
Patrick Baggot, MD
Obstetrics/Gynecology
NPI 1144319609
3020 WILSHIRE BLVD SUITE 219
Los Angeles, CA 90010
(213) 386-2606
✔ PECOS54 mi
Alireza Abidi, M.D.
Gynecological Oncology
NPI 1215919477
4860 Y ST OB/GYN, SUITE 2500
Sacramento, CA 95817
(916) 734-6930
✔ PECOS✔ Accepts Medicare384 mi
Jasmaine Coleman, DO
Obstetrics/Gynecology
NPI 1073042917
550 PEACHTREE ST NE
Atlanta, GA 30308
(404) 872-3121
✔ PECOS✔ Accepts Medicare1,886 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate for Provider-Performed Microscopy Procedures (PPMP) 05D0947120

Valley Obstetrics & Gynecology Medical Group, Inc · Colton, CA
Active · expires Aug 31, 2028
CLIA Number05D0947120
Laboratory TypePhysician Office
Certificate Effective DateSeptember 1, 2026
Certificate Expiration DateAugust 31, 2028
Laboratory DirectorShirley Wong
Laboratory Phone(909) 580-3470
Laboratory LocationValley Obstetrics & Gynecology Medical Group, Inc400 N Pepper St 2mob206, Colton, CA 92324
CLIA data matches this NPI record on: Name
This certificate is issued to a laboratory in which a physician, midlevel practitioner or dentist performs no tests other than the microscopy procedures. This certificate permits the laboratory to also perform waived tests.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Valley Obstetrics & Gynecology Medical Group, Inc.'s NPI number?

The NPI number for Valley Obstetrics & Gynecology Medical Group, Inc. is 1144304817. It was assigned to this organization in the NPPES registry on October 25, 2006.

Where is Valley Obstetrics & Gynecology Medical Group, Inc. located?

Valley Obstetrics & Gynecology Medical Group, Inc. is located at 400 N Pepper Ave, Colton, CA 92324. The listed phone number is (909) 580-6333.

What is Valley Obstetrics & Gynecology Medical Group, Inc.'s specialty?

The primary specialty registered for this NPI is Obstetrics & Gynecology with taxonomy code 207V00000X.

Is Valley Obstetrics & Gynecology Medical Group, Inc. enrolled in Medicare?

Yes. Valley Obstetrics & Gynecology Medical Group, Inc. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Valley Obstetrics & Gynecology Medical Group, Inc.?

According to the CMS Revalidation Reassignment List (October 2026 release), 20 clinicians in 2 Medicare specialties reassign their Medicare billing to Valley Obstetrics & Gynecology Medical Group, Inc.. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. The largest specialties are Obstetrics/Gynecology (19) and Gynecological Oncology (1). Of these, 10 practice within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Valley Obstetrics & Gynecology Medical Group, Inc. hold a CLIA laboratory certificate?

Yes. A Certificate for Provider-Performed Microscopy Procedures (PPMP) (number 05D0947120) is associated with this NPI, valid through August 31, 2028. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

When was this NPI record last updated?

The NPPES record for Valley Obstetrics & Gynecology Medical Group, Inc. was last updated on May 29, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.