[An investigation and design of apparatus for measuring fetal lung maturity]

Clinically, the authorized method for determing fetal lung maturity is the measurement of the ratio of surface-active L/S in amniotic fluid. To set up new, simple, rapid and accurate method, an apparatus for measuring fetal lung maturity was made. The paper describes the basic principle and working procedure of the apparatus. 148 amniotic fluid specimens from different pregnancies were measured by means of the apparatus. The result was compared with the L/S. The sensitivity of measurement was 95%, specificity 91%, and accuracy 93%. The operation of the apparatus is simple, convenient and rapid. A small quantity of amniotic fluid is needed. In conclusion, the expected result was attained. The apparatus is of great importance to clinical application.