[The place of ultrasound diagnosis in obstetrics]

A review is presented of the diagnostic applications of the ultrasonic scan technique in obsterics. In the 1st trimester of pregnancy the demonstration of the gestational sac and of an embryo is most important. During the further course of pregnancy the growth of the gestational sac and motions of the fetus can be observed. A disturbance in the development of the pregnancy can be deduced from these parameters. The various types of abortion can be differentiated by means of the scan. In the 2nd trimester the biometry of the fetus is most important. The motion behaviour of the fetus seems to be a good indicator of its well-being. The location of the placenta and the evidence of twins are easily demonstrable. In the 3rd trimester the biometry of the fetus is a good parameter of its maturity. The diagnosis of the fetal position is important for the management of delivery. Apart from these applications of ultrasound in obstetrics, the procedure is of great value in the diagnosis of tumours and the measurement of the true pelvis in pregnancy.