Gillian Brennan
NPI 1174782437 · Neonatal-Perinatal Medicine Physician · Chicago, IL
Enrolled with Medicare as Practitioner - Pediatric Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Provider details
- NPI number
- 1174782437
- Entity type
- Individual
- Primary specialty
- Neonatal-Perinatal Medicine PhysicianAllopathic & Osteopathic Physicians
- Sex
- Female
- Sole proprietor
- No
- License
- 036122278 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
18 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2008-06-03
- Last updated
- 2022-10-24
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.