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 10/5/2020
Updated by: John D. Jacobson, MD, Professor of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda Center for Fertility, Loma Linda, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. 10