Early ultrasound for pregnancy dating
The bright white circle center-right is the head, which faces to the left.
Features include the forehead at 10 o'clock, the left ear toward the center at 7 o'clock and the right hand covering the eyes at .
Obstetric ultrasonography is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real-time visual images of the developing embryo or fetus in its mother's uterus (womb).
The procedure is a standard part of prenatal care in many countries, as it can provide a variety of information about the health of the mother, the timing and progress of the pregnancy, and the health and development of the embryo or fetus.
Fortunately, gestational sac, yolk sac and embryo are surrounded by hyperechoic (brighter) body tissues.
Traditional obstetric sonograms are done by placing a transducer on the abdomen of the pregnant woman.
One variant, a transvaginal sonography, is done with a probe placed in the woman's vagina.
Transvaginal scans usually provide clearer pictures during early pregnancy and in obese women.
Also used is Doppler sonography which detects the heartbeat of the fetus.
Doppler sonography can be used to evaluate the pulsations in the fetal heart and bloods vessels for signs of abnormalities.