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DR. GILLIAN CLARE PET MD
NPI 1639478969
Pediatrics - Neonatal-Perinatal Medicine in Saint Louis, MO

Active since March 25, 2011PECOS Enrolled
1 CHILDRENS PL, DIV PED NEWBORN MEDICINE, SAINT LOUIS, MO 63110(314) 454-2683(314) 454-4633 Get Directions Write a Review

NPPES record last updated: April 17, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Apr 25, 2024, Apr 10, 2024, Aug 30, 2023 and 6 more (9 updates tracked since 2017).

About Dr. Gillian Clare Pet Md NPPES

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

DR. GILLIAN CLARE PET MD (NPI 1639478969) is an individual neonatal-perinatal medicine provider in Saint Louis, Missouri, licensed in Missouri (2018010173) and active in the NPI registry since March 2011. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1639478969
Entity TypeIndividualFemale
Primary Taxonomy2080N0001X
Provider Legal NameDR. GILLIAN CLARE PETCredential: MD
Location Address1 CHILDRENS PL, DIV PED NEWBORN MEDICINESaint Louis, MO 63110-1002
Mailing AddressPo Box 7412011Chicago, IL 60674-2011 · (314) 454-2683 · Fax (314) 454-4633
Phone(314) 454-2683
Fax(314) 454-4633
Sole ProprietorNo
Enumeration DateMarch 25, 2011
Last NPPES UpdateApril 17, 20259 updates tracked since enumeration
✔ NPI 1639478969 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyPediatrics · Neonatal-Perinatal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code2080N0001X
License✔ Licensed in MO · 2018010173
Definition
A pediatrician who is the principal care provider for sick newborn infants. Clinical expertise is used for direct patient care and for consulting with obstetrical colleagues to plan for the care of mothers who have high-risk pregnancies.
Also ListedPediatricsTaxonomy 208000000X · License 2018010173 (MO)
1 CHILDRENS PL, Saint Louis, MO 63110
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Other Identifiers 1

Medicaid200058592MO

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Cox HealthPlans.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Gillian Clare Pet Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

2

Medicare enrollment records show Gillian Pet reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Washington University
Same address
Multi-Specialty
1 CHILDRENS PL
Saint Louis, MO 63110
  • Reassigned Medicare billing, Missouri enrollment
  • 628 clinicians in this Medicare group
NPI 1194765685 (314) 286-1264
Washington University Physicians In Illinois, Inc
0.2 mi
Multi-Specialty
4901 FOREST PARK AVE STE 341
Saint Louis, MO 63108
  • Reassigned Medicare billing, Illinois enrollment
  • 530 clinicians in this Medicare group
NPI 1457203135 (314) 454-8181

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

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

ARIE BAKER MSW, LCSW
Social Worker (Clinical)
1 CHILDRENS PL, CAMPUS BOX 8116
SAINT LOUIS, MO 63110
St. Louis City (314) 747-6169
SUSAN CHEUNG WALSH AUD
Audiologist-Hearing Aid Fitter
1 CHILDRENS PL
SAINT LOUIS, MO 63110
St. Louis City (314) 454-4649
MS. JENNIFER MARIE JACOBI PNP
Nurse Practitioner (Pediatrics)
1 CHILDRENS PL, DEPT NEUROLOGICAL SURGERY, STE 4E
SAINT LOUIS, MO 63110
St. Louis City (314) 362-3577
MS. EMILY LINCOLN RN, NNP-BC
Nurse Practitioner (Neonatal, Critical Care)
1 CHILDRENS PL
SAINT LOUIS, MO 63110
St. Louis City (314) 454-6000
MS. MARISSA ROSE PEREZ-MAGNELLI PNP
Nurse Practitioner (Pediatrics)
1 CHILDRENS PL, DEPT NEUROLOGY, STE 2130
SAINT LOUIS, MO 63110
St. Louis City (314) 454-6120
MRS. BRIANNA LYNN RICHTER NNP-BC
Nurse Practitioner (Neonatal)
1 CHILDRENS PL
SAINT LOUIS, MO 63110
St. Louis City (314) 454-6000
DR. WILLIAM L RIVES MD
Hospitalist
1 CHILDRENS PL, DIV PED HOSPITALIST MED
SAINT LOUIS, MO 63110
St. Louis City (314) 454-2076
DR. PETER M KILBRIDGE MD
Pediatrics
1 CHILDRENS PL, SUITE C
SAINT LOUIS, MO 63110
St. Louis City (314) 454-2479

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 Gillian Pet's NPI number?

The NPI number for Gillian Pet is 1639478969. It was assigned to this individual provider in the NPPES registry on March 25, 2011.

Where is Gillian Pet located?

Gillian Pet practices at 1 Childrens Pl Div Ped Newborn Medicine, Saint Louis, MO 63110. The listed phone number is (314) 454-2683.

What is Gillian Pet's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Neonatal-Perinatal Medicine, with taxonomy code 2080N0001X.

Is Gillian Pet enrolled in Medicare?

Yes. Gillian Pet is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Gillian Pet's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gillian Pet reassigns Medicare benefits to 2 organizations: Washington University (Saint Louis, MO) and Washington University Physicians In Illinois, Inc (Saint Louis, MO). Each 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 Gillian Pet's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Gillian Pet accept?

Health plans from Cox HealthPlans list Gillian Pet as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Gillian Pet was last updated on April 17, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 months 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.