Significance of absent amniotic fluid in labour following spontaneous or artificial rupture of the membranes

Summary

The obstetric outcome of 192 women who failed to drain amniotic fluid during labour was studied. All the women had ruptured membranes as a consequence of either spontaneous rupture of the membranes before labour or following amniotomy. The latter was performed either at the time of diagnosis of labour in women with spontaneous onset of labour or in order to induce labour. No amniotic fluid was observed at amniotomy or throughout the course of labour. Following delivery of the fetus, 38 per cent of these women drained clear amniotic fluid, 33 per cent continued to have absent amniotic fluid while 29 per cent drained meconium-stained amniotic fluid. When compared with those patients who were observed to drain amniotic fluid during labour or at amniotomy, patients with absent amniotic fluid had a three-fold increase in the incidence of fetal heart rate abnormalities requiring fetal blood sampling, a three-fold increase in forceps delivery and a four-fold increase in caesarean section performed for suspected fetal distress. The finding of absent amniotic fluid early in labour in women with ruptured membranes is a predictor of increased fetal risk and of increased obstetric intervention.