Antonio E. Frias, Jr., MD

Clinical experience in caring for high-risk pregnancies inspires dedication to develop improved methods to identify and treat pregnancies with placental dysfunction.  Dr. Frias specializes in using advanced imaging of the placenta to understand factors that affect placental development and nutrient transport.  A specific focus is the impact of maternal nutrition on placental function, reproductive outcomes, and fetal programming.  The adverse obstetric outcomes attributed to both obesity and diabetes in humans are confounded by an inability to separate the contributions of maternal diet.  Dr. Frias' research resulted in the first report of placental hemodynamic abnormalities in a primate placenta that are secondary to a high fat diet, suggesting that a Western style diet may have an independent impact on the adverse obstetric and neonatal consequences reported in the obese human population.  As the placenta regulates nutrient flow from mother to fetus, it likely occupies a central role in mediating the adverse obstetric/neonatal risks associated obese and/or diabetic pregnancies.  Current assessments of placental function (both clinical and research) are limited by an inability to link in vivo placental perfusion with functional outcomes, such as histopathology and nutrient transport.  Dr. Frias and his collaborators have developed new imaging protocols to quantify placental blood flow creating perfusion maps that can be correlated with placental histopathology and nutrient transport.  These novel studies will set the framework for understanding how the placenta develops and adapts to adverse conditions and will lead to exciting future studies of blood flow on nutrient transfer, and perhaps improved imaging techniques to identify placental dysfunction in humans.  Given the central focus of the placenta on fetal development, Dr. Frias collaborates with scientists and clinicians at OHSU from the divisions of pathology, cardiology, endocrinology, radiology, the Advanced Imaging Research Center, and the Center for Developmental Health. As the primary ultrasound diagnostic imager based at ONPRC, Dr. Frias also supports the NHP work at ONPRC by providing imaging capabilities to scientists in the Division of Reproductive & Developmental Sciences (DRDS) and the Division of Neuroscience. 



Antonio Frias is an Assistant Professor in the Division of Reproductive & Developmental Sciences, and Associate Professor and Maternal Fetal Medicine (MFM) subspecialist in the Department of Obstetrics & Gynecology, Director of the Diabetes and Pregnancy Program at OHSU and Director of the Maternal Fetal Medicine Fellowship.  He completed medical school at the Mayo Clinic (1998), residency training in Obstetrics and Gynecology at the University of Utah (2002), and fellowship training in MFM at the University of Utah (2005).  He joined the ONPRC as a Women's Reproductive Health Research Fellow in 2007.  Dr. Frias also serves on the OHSU Institutional Review Board.  He is a reviewer for OHSU clinical research grants funded by the Center for Women's Health Circle of Giving and the Moore Institute for Nutrition and Wellness.

Key Publications

Frias AE, Schabel MC, Roberts VHJ, Grigsby PL, Oh KY, Tudorica A, Grove KL and Kroenke CD. (2015). Using dynamic contrast enhanced MRI to quantitatively characterize maternal vascular organization in the primate placenta. Magnetic Resonance in Medicine 2015;73(4);1570-8. PMCID: PMC4487918

O'Tierney-Ginn P, Roberts VHJ, Gillingham M, Walker J, Glazebrook PA, Thornburg

KL, Grove KL and Frias AE. (2015). Influence of high fat diet and resveratrol supplementation of placental fatty acid uptake in the Japanese macaque. Placenta;36(8);903-10. PMCID: PMC4529757

Oh, KY, Roberts VHJ, Schabel MC, Grove KL, Woods M and Frias AE. (2015). Gadolinium chelate contrast in pregnancy: fetal biodistribution in the nonhuman primate. Radiology;276(1): 110-8. PMCID: PMC4485748

Lo JO, Schabel MC, Roberts VHJ, Morgan TK, Rasanen JP, Kroenke CD, Shoemaker SR, Spindel ER and Frias AE (2015). Vitamin C supplementation ameliorates the adverse effects of nicotine on placental hemodynamics and histology in nonhuman primates. American Journal of Obstetrics &Gynecology;212(3):370.el-8, Cover Photo. PMCID: PMC4347872

Roberts VHJ, Pound LD, Thorn SR, Gillingham MB, Thornburg KL, Friedman JE, Frias AE*, and Grove KL* (2014). Beneficial and cautionary outcomes of resveratrol supplementation in pregnant nonhuman primates. FASEB Journal;28(6):2466-77. PMID: 24563374  *co-corresponding authors 

Ma J, Prince AL, Bader D, Hu M, Ganu R, Baquero K, Blundell P, Harris A, Frias AE, Grove KL and Aagaard KM. (2014). High fat maternal diet during pregnancy persistently alters the offspring microbiome in a primate model. Nature Communications;5:3889. PMCID: PMC4078997

See a full listing of Dr. Frias' publications.