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Obstetrics/Gynecology

Carmen J. Sierra, MD

Sees patients in San Juan, PR · Puerto Rico

Summary

Dr. Carmen J. Sierra, MD is an OB-GYN at 400 Calle Manuel Domenech, Suite 311, San Juan, PR 00918. Phone: (787) 281-8522. Accepts Medicare assignment. In 2024, Carmen J. Sierra had 26 Original Medicare patients and 54 services. NPI 1972539054. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: OB-GYN (Medicare lists Obstetrics/Gynecology)
  • Address: 400 Calle Manuel Domenech, Suite 311, San Juan, PR 00918 · Directions (1 more location)
  • Phone: (787) 281‑8522
  • Medicare: Accepts Medicare assignment
  • Medical school: graduated 1988 (38 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Carmen J. Sierra, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Carmen J. Sierra accept Medicare assignment?
Yes. Medicare's clinician data says Carmen J. Sierra accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Carmen J. Sierra see?
In 2024, CMS data shows 26 Original Medicare patients and 54 services for Carmen J. Sierra. This counts Original Medicare only and measures volume, not quality.
What is Carmen J. Sierra's NPI number?
1972539054. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Carmen J. Sierra, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients26
Services billed to Medicare54
Different services or procedures6
Participating Medicare providerYes
Average age of these patients72

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)44 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Osteoporosis65%
  • Diabetes62%
  • Arthritis54%

Practice locations

Addresses where Carmen J. Sierra is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Obstetrics/Gynecology doctors in Puerto Rico →

Other OB-GYNs in San Juan

Clinicians with the same Medicare primary specialty in San Juan, PR — not a recommendation.

All OB-GYNs in San Juan →

Clinician information

CredentialMD
Graduation year1988 (38 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1972539054
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians