This is a normal ultrasound performed at 17 weeks gestation. It shows the placenta during a normal (Braxton Hicks) contraction. Throughout the pregnancy, the uterus periodically contracts to facilitate better blood flow through the placenta and the fetus. In this ultrasound, the placenta can be seen as the mound-shaped object in the middle of the screen. At the bottom of the image, the mother's vertebra can be seen as a round object. When the uterus is not contracting, the placenta would appear much flatter.
Review Date: 11/8/2012 Reviewed By: Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Bellevue, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.