Welcome to Riverwalk OBGYN

Overall patient rating:

In 1979 Tristan Castaneda, MD started with a simple premise: Make available to every woman the health resources she needs to live a healthy, active, and long life. At the same time, educate each woman about the importance of preventative health measures. This same idea still drives us today, some 30 years later. The track record we’ve accumulated over the years speaks to our commitment to patients, their families, and the community at large. Both our medical and office staffs are second to none, who genuinely take an interest in individual patient’s needs. We think you’ll notice the difference immediately when you step foot inside our doors. We’d love to see you today to map out a health and wellness plan that’s tailored to your health history and needs.

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About Our Practice

  • Providers

  • Services

  • Links And Forms

  • Locations

  • Contact Us

  • Alka Arya Degaetano

  • Ricardo Munoz

  • Stephanie Schaefer

  • Christina Simpson

  • Heather Williams


We Provide The Following Services

  • Obstetrics + Reproduction
  • Pregnancy Care and Delivery
  • Contraception
  • Ultrasound and Imaging
  • Gynecology + Wellness
  • Annual Exams
  • Menopause
  • Urogynecology

Riverwalk OBGYN: San Antonio Office

  • Monday: 8:30AM - 5:30PM
  • Tuesday: 8:30AM - 5:30PM
  • Wednesday: 8:30AM - 5:30PM
  • Thursday: 8:30AM - 5:30PM
  • Friday: 8:30AM - 5:30PM

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    Patient Reviews

    Overall patient rating for Riverwalk OBGYN:

    Office Visit / Follow-up

    Dr Munoz and Ana are always kind and patient with all the visits

    Pap Smear

    Very professional !!!

    Childbirth / Labor & Delivery

    She is very kind and listened to all my worries, dr Arya makes you feel peaceful.

    Pap Smear

    A new patient of Dr. Schaefer. She was thorough in going through my history.

    Obstetrical (Pregnancy) Ultrasound / Sonogram

    Dr Arya is always so kind and gentle! She makes sure that I leave having all of my questions answered

    Gynecological Exams

    Very comforting and informative


    Dr Arya an awesome and professional doctor

    Gynecological Problem Visit

    Service was amazing front start to finish. Appointments were made quickly, staff was friendly and efficient, wait time was minimal, doctors visit was great.

    Annual Well Woman Exam

    Dr Muñoz was very kind and patient listening and explaining about my health. Very careful while doing the procedure. He is very professional and human being.

    Gynecological Problem Visit

    Did not have to wait long. And Dr. Simpson is very detailed and takes her time which I love.