Pregnancy is a physiological state which still needs close observation from the very beginning till the delivery to decrease the potential risk of complications for the mother and her baby. The finding of pathology is possible thanks to advanced diagnostic technology--cardiotocograph and ultrasonography, especially Doppler technique. Monitoring of the fetus is based not only on the routine obstetric examination, but also on the observation and analysis of the fetal heart rate, biometry measurements with expected fetus weight, as well as assessment of blood flow in the fetal, the umbilical and uterine vessels. Assuming that pathology in fetal heart rate can predict intrauterine discomfort, early examination and appropriate reaction to the situation is essential. Early identification of intrauterine growth restriction enables intensive treatment which improves the outcome and reduces perinatal mortality. Information concerning biophysical monitoring of a fetus and basic rules of test result interpretations of are presented in this article.