[Study and application on the device of the drop volume of amniotic fluid in estimating fetal lung maturity]

A novel device of drop volume of amniotic fluid has been made to estimate fetal lung maturity. The design of the device is based on the principle that the surface tension of amniotic fluid is inversely proportional to the quantity of surfactant in the solution. The device measures the falling time of fluid drops from drop-tube and estimates the fetal lung maturity by using the method of comparison and electric-optic timing-counting. 148 samples of amniotic fluid were measured by the device and the data were compared with those obtained by biochemical method. The results demonstrate that this device has high stability and accuracy, and the rate of agreement between the two methods is as high as 93%.