Hindawi Publishing Corporation Journal of Pregnancy Volume 2012, Article ID 750485, 11 pages doi:10.1155/2012/750485 Review Article Extrinsic Factors Influencing Fetal Deformations and Intrauterine Growth Restriction Wendy Moh, 1 John M. Graham Jr.,2 Isha Wadhawan,2 and Pedro A. Sanchez-Lara1 1 Center for Craniofacial Molecular Biology, Ostrow School of Dentistry and Children’s Hospital Los Angeles, Keck School of Medicine of the University of Southern California, 4650 Sunset Boulevard, MS 90, Los Angeles, CA 90027, USA 2 Cedars-Sinai Medical Center, Medical Genetics Institute and David Geffen School of Medicine at UCLA, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048, USA Correspondence should be addressed to Pedro A. Sanchez-Lara,
[email protected] Received 24 March 2012; Revised 4 June 2012; Accepted 4 June 2012 Academic Editor: Sinuhe Hahn Copyright © 2012 Wendy Moh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The causes of intrauterine growth restriction (IUGR) are multifactorial with both intrinsic and extrinsic influences. While many studies focus on the intrinsic pathological causes, the possible long-term consequences resulting from extrinsic intrauterine physiological constraints merit additional consideration and further investigation. Infants with IUGR can exhibit early symmetric or late asymmetric growth abnormality patterns depending on the fetal stage of development, of which the latter is most common occurring in 70–80% of growth-restricted infants. Deformation is the consequence of extrinsic biomechanical factors interfering with normal growth, functioning, or positioning of the fetus in utero, typically arising during late gestation.