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NATALIA C LLARENA MD
NPI 1083005300
Obstetrics & Gynecology - Reproductive Endocrinology in Pasadena, CA

Active since February 09, 2015PECOS Enrolled
55 S LAKE AVE FL 9, PASADENA, CA 91101(818) 212-7541 Get Directions Write a Review

NPPES record last updated: May 27, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: May 27, 2025, Feb 7, 2025, Mar 18, 2019 (3 updates tracked since 2019).

About Natalia C Llarena Md NPPES

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

NATALIA C LLARENA MD (NPI 1083005300) is an individual reproductive endocrinology provider in Pasadena, California, licensed in California (A177111) and active in the NPI registry since February 2015. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1083005300
Entity TypeIndividualFemale
Primary Taxonomy207VE0102X
Provider Legal NameNATALIA C LLARENACredential: MD
Location Address55 S LAKE AVE FL 9Pasadena, CA 91101-2676
Mailing Address55 S Lake Ave Fl 9Pasadena, CA 91101-2676 · (626) 660-9718
Phone(818) 212-7541
Sole ProprietorNo
Enumeration DateFebruary 9, 2015
Last NPPES UpdateMay 27, 20253 updates tracked since enumeration
NPPES CertifiedFebruary 7, 2025
✔ NPI 1083005300 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyObstetrics & Gynecology · Reproductive EndocrinologyAllopathic & Osteopathic Physicians
Taxonomy Code207VE0102X
License✔ Licensed in CA · A177111
Definition
An obstetrician/gynecologist who is capable of managing complex problems relating to reproductive endocrinology and infertility.
55 S LAKE AVE FL 9, Pasadena, CA 91101
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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Natalia C Llarena 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 Reassignment

Medicare enrollment records show Natalia Llarena reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

University Hospitals Medical Group Inc
2,045 mi
Multi-Specialty
11100 EUCLID AVE
Cleveland, OH 44106
  • Reassigned Medicare billing, Ohio enrollment
  • 3,958 clinicians in this Medicare group
NPI 1669499414 (216) 844-1000

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91101 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 2

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

DR. RICHARD JOHN PAULSON MD
Obstetrics & Gynecology (Reproductive Endocrinology)
55 S LAKE AVE FL 9
PASADENA, CA 91101
Los Angeles County (626) 440-9161
DR. JACQUELINE YANO MAHER M.D.
Obstetrics & Gynecology (Reproductive Endocrinology)
55 S LAKE AVE FL 9
PASADENA, CA 91101
Los Angeles County (323) 409-3026

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 Natalia Llarena's NPI number?

The NPI number for Natalia Llarena is 1083005300. It was assigned to this individual provider in the NPPES registry on February 9, 2015.

Where is Natalia Llarena located?

Natalia Llarena practices at 55 S Lake Ave Fl 9, Pasadena, CA 91101. The listed phone number is (818) 212-7541.

What is Natalia Llarena's specialty?

The primary specialty registered for this NPI is Obstetrics & Gynecology, specializing in Reproductive Endocrinology, with taxonomy code 207VE0102X.

Is Natalia Llarena enrolled in Medicare?

Yes. Natalia Llarena is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Natalia Llarena's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Natalia Llarena reassigns Medicare benefits to University Hospitals Medical Group Inc (Cleveland, OH). The 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 Natalia Llarena's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Natalia Llarena was last updated on May 27, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.