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About me

Pronouns: She | Her | Hers

Dr. Arianna Cassidy is a perinatologist, an obstetrician who specializes in high-risk pregnancies. She cares for patients with pre-existing medical issues that can affect pregnancy as well as conditions that can develop during pregnancy. She also cares for patients who require complex surgery during pregnancy or need C-section births. She has a special interest in placental conditions, particularly placenta accreta spectrum (PAS) disorder (in which the placenta grows into the uterine wall).

Cassidy's research focuses on understanding PAS and improving the care of pregnant patients who develop it, including looking at how providers from relevant specialties can work in concert to prevent, detect and address abnormal development of the placenta. She also studies COVID-19 infection and vaccination in pregnancy, the intersection between maternal-fetal medicine and family planning, and quality improvement measures.

Cassidy earned her medical degree at UCSF, where she also completed a residency in obstetrics and gynecology and a fellowship in maternal-fetal medicine.

  • Board Certifications

    American Board of Obstetrics and Gynecology, Obstetrics & Gynecology

  • Fellowships

    UCSF Graduate Medical Education, Maternal and Fetal Medicine

  • Residencies

    UCSF Graduate Medical Education, Obstetrics & Gynecology

  • Degree

    MD, UCSF School of Medicine

  • Languages

    Spanish

Where I see patients (2)

    My reviews

    4.9

    Overall Experience
    30 Ratings
    About our process
    Feb 07, 2025
    Dr. Cassidy is amazing. She guided me through my pregnancy with care and great advice. So happy she was by OB.
    Jan 27, 2025
    Explained things slowly, clearly, and thoroughly. Very polite and friendly as well!
    Sep 20, 2024
    Dr Cassidy blew me away with her kindness, empathy, and expertise
    Sep 09, 2024
    Great staff!! Very welcoming and informative!
    Apr 24, 2024
    Extremely positive experience. She was incredibly thorough, deliberate, and kind. She gave me tons of info that really helped me understand the possible issues, and lower my anxiety. I felt like she was very present and compassionate when I was emotional, and extremely thorough and competent when I wanted information. She spent a LONG time with me, and I was so grateful for it.

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