The aim of this study is to determine the frequency of pregnant women having ultrasonography and to evaluate their knowledge and expectations about ultrasonography. Our study included 230 patients who applied to obstetrics and gynecology clinic in a university hospital, who had a pregnancy of 32 weeks or more and agreed to participate in the study. After obtaining the approval of the ethics committee and getting their written consent, a questionnaire consisting of 34 questions was filled by face to face interview method. Pregnant women who were considered to have risky pregnancies in terms of their pregnancies or pre- pregnancy conditions and who need frequent follow-up were not included in the study. The questionnaires were evaluated using the SPSS version 22.0 program. According to the findings obtained from the study, 39.1% of the pregnant women participating in the study think that there is radiation on the ultrasound, just like on a direct radiograph (x-ray). These pregnant women also stated that they know that radiation is harmful for them and their babies. 90% of these pregnant women had ultrasound at each control, and 24.4% had an extra ultrasound to learn the baby's gender. If their doctor is told that it will be enough to do ultrasound four times during pregnancy, 65.6% of the pregnant women reported that they would change their doctor. An ultrasound examination was performed at each control to 90.1% of the pregnant women who stated that the ultrasound was harmful. 27.1% of pregnant women who went to the doctor for extra control for gender think that ultrasound is harmful. 37.3% of pregnant women who had three-dimensional (3D) ultrasound had this done without a doctor's recommendation. Ultrasound should be used in ethically appropriate indications during pregnancy follow-up.