[Orange colored cells in the amniotic fluid. Statistical evaluation of 504 samples]

The authors have made a statistical evaluation of 504 estimations of the percentage of orange coloured cells in the liquor amnii. They have been able to draw up a curve of the means which confirms the value of this method. Orange coloured cells of fetal origin first appear after about 28 to 30 weeks. The rise in the percentage which is gradually progressive between the 30th and 37th weeks becomes sharp at the 38th week. The gradients of the curve of the means between the 37th and 38th week is comparable to that of the ratio lecithin/sphingomyelin. It is different from that of creatinaemia which is steeper. False-positive results are rare: at 2 p. 100 they seem to correspond to an advance in fetal maturation which may be spontaneous or may be brought about by treatment. False-negative results are commomer: 13 p. 100. The percentage of orange coloured cells should be viewed in conjunction with other tests for maturity. The technique is simple but the results may be vitiated by the minutae of preservation, of taking or of staining the cells which are described. Orange coloured cells maintain their value in pathological pregnancies and in particular in those where the fetuses are small for dates, for the percentage of orange coloured cells agrees more with the age of the fetus than with its weight.