Photo of Antonio E. Frias, M.D.

Antonio E. Frias M.D.

Dr. Frias has a special interest in diabetes mellitus, thrombophilias, recurrent pregnancy loss and fetal anemia (RH disease). His current research focuses on placental development, obesity and nutrition. Dr. Frias finds it rewarding to educate patients about their health and help them in making the best health care decisions. He enjoys providing medical care throughout complicated pregnancies so that his patient can have an optimal outcome as well as a good experience.

Born in Houston, Texas, Dr. Frias loves living the Pacific Northwest. He's happy to be in Portland because he finds it to be a blend of an outdoor haven with a quirky, fun personality. In his leisure time, Dr. Frias enjoys skiing, cycling, rooting for the Portland Timbers soccer team and spending time with his amazing family and friends.

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  • M.D., Mayo Medical School, Rochester Minnesota 1998
  • Residency:

    • Obstetrics and gynecology, University of Utah, Salt Lake City, 2002
  • Fellowship:

    • Maternal-fetal medicine, obstetrics and gynecology, University of Utah, Salt Lake City, 2005
  • Certifications:

    • American Board of Obstetrics and Gynecology, 2005

Memberships and associations

  • Society of Maternal Fetal Medicine


  • "Maternal high-fat diet disturbs uteroplacental hemodynamics and increases the frequency of stillbirth in a nonhuman primate model of excess nutrition" Obstetrical and Gynecological Survey October 2011
  • "Fetal ventricular diastolic filling characteristics in a primate model" Reproductive Sciences August 2010
  • "Impact of maternal obesity on fetal programming of cardiovascular disease" Physiology  2015
  • "Maternal high-fat diet disturbs uteroplacental hemodynamics and increases the frequency of stillbirth in a nonhuman primate model of excess nutrition" Endocrinology June 2011
  • "Robo4 stabilizes the vascular network by inhibiting pathologic angiogenesis and endothelial hyperpermeability" Nature Medicine April 2008
  • "Fetal pulmonary arterial vascular impedance reflects changes in fetal oxygenation at near-term gestation in a nonhuman primate model" Reproductive Sciences January 2013
  • "Fetal schizencephaly" Radiographics May 2005
  • "Gadolinium chelate contrast material in pregnancy" Radiology July 1 2015
  • "Obesity" Seminars in Reproductive Medicine  2012
  • "Post Magpie" Current Opinion in Obstetrics and Gynecology December 2003
  • "Corrigendum" Nature Medicine May 2008
  • "Influence of high fat diet and resveratrol supplementation on placental fatty acid uptake in the Japanese macaque" Placenta August 1 2015
  • "The aryl hydrocarbon receptor nuclear translocator gene polymorphism in patients with recurrent miscarriage" American Journal of Reproductive Immunology and Microbiology January 2006
  • "Restriction of placental vasculature in a non-human primate" Placenta January 2012
  • "Unilateral short femur - What does this mean?" Ultrasound Quarterly June 2008
  • "Poor obstetric outcome in subsequent pregnancies in women with prior fetal death" Obstetrics and Gynecology September 2004
  • "High-fat maternal diet during pregnancy persistently alters the offspring microbiome in a primate model" Nature Communications May 20 2014
  • "What is the optimal gestational age for women with gestational diabetes type A1 to deliver?" American Journal of Obstetrics and Gynecology October 1 2014
  • "Preoperative serum level of inhibin a is an independent prognostic factor for the survival of postmenopausal women with epithelial ovarian carcinoma" Cancer  1999
  • "Beneficial and cautionary outcomes of resveratrol supplementation in pregnant nonhuman primates" FASEB Journal  2014
  • "The fetal posterior fossa" Ultrasound Quarterly September 2007
  • "Using dynamic contrast-enhanced MRI to quantitatively characterize maternal vascular organization in the primate placenta" Magnetic Resonance in Medicine April 1 2015
  • "The effect of race/ethnicity on adverse perinatal outcomes among patients with gestational diabetes mellitus" American Journal of Obstetrics and Gynecology October 2012
  • "Vitamin C supplementation ameliorates the adverse effects of nicotine on placental hemodynamics and histology in nonhuman primates" American Journal of Obstetrics and Gynecology March 1 2015
  • "When is the optimal time to deliver late preterm IUGR fetuses with abnormal umbilical artery Dopplers?" Journal of Maternal-Fetal and Neonatal Medicine March 3 2016
  • "Functional imaging of the nonhuman primate Placenta with endogenous blood oxygen level–dependent contrast" Magnetic Resonance in Medicine November 1 2016
  • "Genomic Variants Associated with Resistance to High Fat Diet Induced Obesity in a Primate Model" Scientific Reports November 4 2016
  • "Folding, but not surface area expansion, is associated with cellular morphological maturation in the fetal cerebral cortex" Journal of Neuroscience February 22 2017
  • "IFPA meeting 2016 workshop report II" Placenta January 10 2017
  • "Quantitative assessment of placental perfusion by contrast-enhanced ultrasound in macaques and human subjects" American Journal of Obstetrics and Gynecology March 1 2016

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