Abstract

The fluorescence probe 1,6, diphenyl-1,3,5-hexatriene was used to determine the micro-viscosity of third trimester amniotic fluid samples utilising an Aminco Bowman spectrofluorometer fitted with a polariser prism. The results were related to the lecithin sphingomyelin (L:S) ratio. A fluorescence polarisation value of 0.360 corresponded to an L:S ratio of 2.0 in uncomplicated and diabetic pregnancies. Pregnancies complicated by Rhesus disease gave significantly different fluorescence polarisation values when compared with the uncomplicated pregnancies.