Antepartum fetal risk assessment: the role of the fetal biophysical profile score.

In the art of medicine we have always known that establishing an accurate diagnosis of health or disease is essential. An active search for the physical signs, both the time honoured and newly discovered, are a crucial step in achieving diagnostic accuracy, in monitoring disease progression, and in assigning prognosis. In extrauterine medicine it is common practice to gather together sets of biophysical data in order to determine immediate health, to monitor condition, and to estimate prognosis: witness the use of vital signs, and, in the newborn, the Apgar score. The providers of perinatal care have known since biblical days that fetal biophysical activities were a reflection of fetal condition (Luke: Chapter 1, Verses 44-45), yet lacked the ability to categorize these activities in an objective and complete manner. The introduction of dynamic ultrasound imaging methods to perinatal medicine at last create the window through which the principles of extrauterine medicine may now be applied to the intrauterine patient--the fetus. Fetal biophysical profile scoring is a method that utilizes this new wealth of information to differentiate the normal fetus from the fetus at risk for death or damage in utero. The method is based on the concept that the discrimination of fetal health and disease improves as more variables are considered. The now extensive clinical experience with the method, in which both overall (gross) and selected (corrected) perinatal death are reduced, while maintaining a remarkably low false negative predictive error, indicate the validity of the concept. Comparative studies lead us to believe that reliance upon single biophysical variables, such as fetal movement counts, or antepartum fetal heart rate monitoring, is no longer of sufficient accuracy to support its use as a sole measure of fetal condition. Looking forward, we anticipate that while the concept on which fetal biophysical profile scoring is based will remain unchanged, inclusion of additional variables is likely to occur. It seems likely that addition of new variables, as may be now measured using high-resolution dynamic ultrasound methods, both B-mode and Doppler, will improve diagnostic accuracy even more. We believe that the application of the current and future modified methods of composite fetal risk assessment will render the occurrence of the tragedy of perinatal loss even more infrequent. While the goal of complete elimination of perinatal deaths remain elusive, this method may be one step towards this goal.