[Study of fetal respiration by ultrasound. Correlation with gestational age and diagnosis of fetal distress].

The authors, following the work of Boddy and Robinson, studied the value of recording fetal breathing activity in the antenatal diagnosis of fetal distress. Fetal respiratory movements are detected with unidimensional echography, thanks to an electronic grille which is able to isolate a thoracic echo which is then reproduced on a rapid recorder after amplification. In normal pregnancies there is a highly significant correlation between fetal respiratory activity and the length of amenorrhoea. In a series of twelve cases with fetal distress that were recorded during labour and were defined after delivery by an Apgar score of less than or equal to 6 and an umbilical arterial pH less than or equal to 7.17, prenatal recordings showed a pathological reduction in fetal breathing movement in 9 cases. In this series only 5 cardiotocograms were shown to be abnormal.