FURTHER STUDIES IN THE ASSESSMENT OF GESTATIONAL AGE BY AMNIOTIC FLUID ANALYSIS

Abstract

Summary Gestational age was assessed by measurement of the liquor amnii creatinine concentration in 65 normal pregnancies and in 33 pregnancies where rhesus iso‐immunization was suspected or had occurred. A total of 154 creatinine estimations were performed. The gestational age was also assessed by amniotic fluid cytology in 60 of these cases. Comparison of the results suggests that fetal maturity of more than 36 weeks is associated with a creatinine concentration in excess of 1·7 mg. per cent or an orange‐staining cell count in excess of 10 per cent. When the orange‐staining cell count was less than 10 per cent then creatinine estimation was found to improve the accuracy of prediction of fetal maturity.