Sara Jean Slezak, D.O.

Primary specialty

Obstetrics & Gynecology PhysicianTaxonomy code 207V00000X

License

036.161001 Issued in IL

Practice address

2001 S California Ave Ste 100
Chicago, IL 60608-2486

Phone

(773) 584-6200

NPI assigned

Jun 17, 2018

Sex

Female

Sole proprietor

No

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 1

Addresses

Other names 1

• Sara Jean Twiehaus Former name

Medicare fee-for-service enrollment

Enrolled in IL

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 1

Specialty

Obstetrics/Gynecology

Education

Midwestern University, Chicago College of Osteopathic Med, 2018

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Endeavor Health Medical GroupGroup PAC ID 2163334699, 3,330 clinicians

Practice addresses (Care Compare)

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Osteopathy

State licenses

Practice roles

Locations

Interoperability endpoints

• FHIR API: https://api.platform.athenahealth.com/11903/brand/1/csg/1/fhir/r4

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Endeavor Health Medical Group

  dba NorthShore University HealthSystem Faculty Practice Associates

  • Emergency Medicine Physician
  • Evanston, IL
  • NPI 1497701882

  Obstetrics & Gynecology

  Medicare reassignment Care Compare group NPD
• Esperanza Health Centers

  • Federally Qualified Health Center (FQHC)
  • Chicago, IL
  • NPI 1124187125
  Medicare reassignment NPD
• Rush University Medical Group

  dba Rush University Internists

  • Internal Medicine Physician
  • Chicago, IL
  • NPI 1093819542

  Obstetrics & Gynecology

  Medicare reassignment NPD
• Saint Anthony Health Affiliates

  • Multi-Specialty Clinic/Center
  • Chicago, IL
  • NPI 1881086064
  Medicare reassignment NPD
• Endeavor Health Medical Group

  dba NorthShore Anesthesia Group

  • Anesthesiology Physician
  • Evanston, IL
  • NPI 1265695944
  NPD
• Esperanza Health Centers

  dba Lakeshore Hotel Shelter

  • Federally Qualified Health Center (FQHC)
  • Chicago, IL
  • NPI 1659127199
  NPD
• Rush University Medical Center

  dba Rush Oak Brook

  • Internal Medicine Physician
  • Oak Brook, IL
  • NPI 1801375696

  Obstetrics & Gynecology

  NPD
• Saint Anthony Health Affiliates

  • Multi-Specialty Clinic/Center
  • Chicago, IL
  • NPI 1295757771

  Obstetrics & Gynecology

  NPD
• Esperanza Health Centers

  dba Esperanza at Cultivate Collective

  • Federally Qualified Health Center (FQHC)
  • Chicago, IL
  • NPI 1265114623
  NPD (past)
• Esperanza Health Centers

  dba Daley College Shelter

  • Federally Qualified Health Center (FQHC)
  • Chicago, IL
  • NPI 1316793813
  NPD (past)
• Esperanza Health Centers

  dba Esperanza Little Village

  • Federally Qualified Health Center (FQHC)
  • Chicago, IL
  • NPI 1477812030
  NPD (past)

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1529193600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1769040000000",
    "number": "1285128926",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "2650 RIDGE AVE STE 1223",
            "city": "EVANSTON",
            "state": "IL",
            "postal_code": "602011700",
            "telephone_number": "847-570-2040",
            "fax_number": "847-570-5315"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "2001 S CALIFORNIA AVE STE 100",
            "city": "CHICAGO",
            "state": "IL",
            "postal_code": "606082486",
            "telephone_number": "773-584-6200"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "5140 N California Ave Ste 605",
            "address_purpose": "LOCATION",
            "city": "Chicago",
            "state": "IL",
            "postal_code": "606253645",
            "country_code": "US",
            "telephone_number": "773-878-7787",
            "fax_number": "773-878-0788",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "SLEZAK",
        "first_name": "SARA",
        "middle_name": "JEAN",
        "name_prefix": "Dr.",
        "credential": "D.O.",
        "sole_proprietor": "NO",
        "sex": "F",
        "enumeration_date": "2018-06-17",
        "last_updated": "2026-01-22",
        "certification_date": "2026-01-22",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207V00000X",
            "taxonomy_group": "",
            "desc": "Obstetrics & Gynecology",
            "state": "IL",
            "license": "036.161001",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": [
        {
            "first_name": "SARA",
            "last_name": "TWIEHAUS",
            "middle_name": "JEAN",
            "credential": "DO",
            "code": "1",
            "type": "Former Name"
        }
    ]
}

• Mark David Sleeper, PT, MS, OCS
• Sleepologie Health and Wellness LLC
• Katherine Sleman, LCPC
• John Kevin Slepchuk II, MD
• Mitchell Slezak, DPT
• Tammy J Slezak, PTA
• Tarek Slibi, MD
• Caroline Ann Slidell, CRNP
• Sliiip LLC
• William Slikker III, M.D.

• Obstetrics & Gynecology Physician in Chicago, IL
• Providers in Chicago, IL by specialty
• Obstetrics & Gynecology Physician in Illinois

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jan 22, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.