[Umbilical Doppler velocimetry in prolonged pregnancies]

Abstract

One-hundred and eighty-seven single pregnancies, at full term determined accurately and confirmed by ultrasound before 17 weeks of amenorrhea and which were proceeding normally were monitored every 2 days after the expected end of term. This was done by conventional methods and in 132 cases by determining a placental resistance index (R = D/S). All the deliveries were carried out under monitoring and the infants examined by a pediatrician. The umbilical index at 280 to 300 days of gestation was found to be constant and equal to R = 0.52 +/- 0.041 (n +/- D) and the signs of fetal distress and post-maturity increased beyond term. In the first 80 pregnancies studies in this way, the determination of the value of the index R was not included in the decision-making process. Twelve of the 14 cases of fetal heart rate arrhythmia during delivery and all recorded cases of post-mature clinical signs and neonatal acidosis occurred when the index was above RI = 0.54. The next 107 pregnancies were randomly divided into two groups. In the 52 pregnancies in which the Doppler revealed an index at two consecutive determinations in excess of 0.54, this was taken to be a criterion for the induction of childbirth. In this group, some of the women gave birth earlier, without any increase in the number of Caesareans and this resulted in fewer post-mature infants.(ABSTRACT TRUNCATED AT 250 WORDS)