MercyOne Waterloo OB/GYN
Obstetrics and Gynecology • Waterloo, IA • Since 1998
About
MercyOne Waterloo OB/GYN Ste G4500 is part of MercyOne, a nonprofit health system headquartered in Des Moines, Iowa. MercyOne offers orthopedics, cardiology, and general hospital care, with online access to medical records, test results, appointments, and health information. The organization operates primarily in the Midwest (Iowa and surrounding areas) and is owned by Trinity Health. For exact provider, appointment availability, and Ste G4500 suite details, contact MercyOne Waterloo directly or visit mercyone.org for the Waterloo OB/GYN department information.
Clinic Type
Obstetrics and Gynecology
Address
3421 W. 9th St. Ste G4500 Waterloo, IA 50702
Phone
417-???
todd.mizener@mercyone.org
Opening Hours
7:30am - 4:30pm (typical daily hours shown across locations)
Telehealth
Available (Offers Virtual Visits)
Services Offered
Technology & Equipment
Team
Insurance & Payment
—
Languages Spoken
Social Media
Photos
What Patients Say
Overall sentiment across review platforms: positive
- Birdeye: 3.6 out of 5 stars (based on 31 reviews) (31 reviews)
- MercyOne (Dr. Heather Marthers): 4.9 out of 5 stars (58 ratings)
- MercyOne (Dr. Assumpta Twekise): 4.9 out of 5 stars (46 ratings)
- Ratings.MD (Melissa Clark): 4.9 out of 5 stars (92 ratings)
- Ratings.MD (Jane Keller, ARNP): 4.9 out of 5 stars (112 ratings)
- MercyOne (Dr. Rachel Reitan): 4.8 out of 5 stars (36 ratings)
Patients praise
- Compassionate and caring bedside manner
- Providers are knowledgeable and professional
- Effective at listening to patient concerns and explaining medical conditions or procedures clearly
- Staff is friendly and helpful
- Helps patients feel comfortable and at ease during appointments
Common complaints
- Occasional concerns regarding communication during labor and delivery, such as lack of notice about procedures or lack of discussion regarding birth preferences like skin-to-skin contact
"She’s amazing and is so knowledgeable and friendly and helpful best doctor around period!!!"
— Patient review of Dr. Heather Marthers"Even during a terribly invasive procedure I felt secure and safe thanks to their compassion and professional care."
— Patient review of Melissa Clark"She put me at ease right away making the appointment more bearable."
— Patient review of Jane Keller, ARNPSynthesized from public review platforms as of Jul 11, 2026 — sources: [1][2][3][4].
In the News
- MercyOne announces more than 8,500 births in 2025 | MercyOne — Jan 8, 2026
- MercyOne and The Iowa Clinic announce partnership to transition gynecologic oncology services for Central Iowa | MercyOne — Jan 12, 2026
- MercyOne Waterloo welcomes first baby of 2026 | News, Sports, Jobs - Tama-Toledo News Chronicle — Jan 9, 2026
- MercyOne Waterloo welcomes first baby of 2026 | News, Sports, Jobs - North Tama Telegraph — Jan 9, 2026
Information sourced from the clinic's website as of July 11, 2026.
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